From ccb5d0a7c170434bb2ced860ec7139f4c6f964ce Mon Sep 17 00:00:00 2001
From: Scott Wolchok <swolchok@fb.com>
Date: Tue, 16 Jul 2019 13:29:40 -0700
Subject: [PATCH 01/40] Support SDKROOT env var on iOS

Following what clang does (https://github.com/llvm/llvm-project/blob/296a80102a9b72c3eda80558fb78a3ed8849b341/clang/lib/Driver/ToolChains/Darwin.cpp#L1661-L1678), allow allow SDKROOT to tell us where the Apple SDK lives so we don't have to invoke xcrun.
---
 src/librustc_target/spec/apple_ios_base.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/librustc_target/spec/apple_ios_base.rs b/src/librustc_target/spec/apple_ios_base.rs
index 3068ed8d206cd..40cc7f420106b 100644
--- a/src/librustc_target/spec/apple_ios_base.rs
+++ b/src/librustc_target/spec/apple_ios_base.rs
@@ -1,3 +1,4 @@
+use std::env;
 use std::io;
 use std::process::Command;
 use crate::spec::{LinkArgs, LinkerFlavor, TargetOptions};
@@ -27,6 +28,12 @@ impl Arch {
 }
 
 pub fn get_sdk_root(sdk_name: &str) -> Result<String, String> {
+    if let Some(sdkroot) = env::var("SDKROOT").ok() {
+        let sdkroot_path = Path::new(sdkroot);
+        if sdkroot_path.is_absolute() && sdkroot_path != Path::new("/") && sdkroot_path.exists() {
+            return Ok(sdkroot);
+        }
+    }
     let res = Command::new("xcrun")
                       .arg("--show-sdk-path")
                       .arg("-sdk")

From 795f93b8af25a2efd19bd5b01367e827d8da73e5 Mon Sep 17 00:00:00 2001
From: Alex Crichton <alex@alexcrichton.com>
Date: Wed, 17 Jul 2019 09:28:02 -0700
Subject: [PATCH 02/40] ci: Install clang on Windows through tarballs

Previously we used the executables built the LLVM project but these
executables are difficult to run in a CI environment, they can
accidentally pollute global state, etc. In testing some of the possible
4-core machine environments for Azure this step would frequently cause
issues.

To assuage these future issues and hopefully make builds slightly more
self-contained, this commit changes to install from a tarball instead.
The tarball isn't provided by LLVM itself, but we use the offical LLVM
installer to extract itself and then we pack up the LLVM installation
directory into the tarball.
---
 .azure-pipelines/steps/install-clang.yml | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/.azure-pipelines/steps/install-clang.yml b/.azure-pipelines/steps/install-clang.yml
index 0cd6f24e32c7c..45ec767e0b875 100644
--- a/.azure-pipelines/steps/install-clang.yml
+++ b/.azure-pipelines/steps/install-clang.yml
@@ -26,12 +26,18 @@ steps:
 #
 # Original downloaded here came from
 # http://releases.llvm.org/7.0.0/LLVM-7.0.0-win64.exe
-- script: |
-    powershell -Command "$ProgressPreference = 'SilentlyContinue'; iwr -outf %TEMP%\LLVM-7.0.0-win64.exe https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/LLVM-7.0.0-win64.exe"
-    set CLANG_DIR=%CD%\citools\clang-rust
-    %TEMP%\LLVM-7.0.0-win64.exe /S /NCRC /D=%CLANG_DIR%
-    set RUST_CONFIGURE_ARGS=%RUST_CONFIGURE_ARGS% --set llvm.clang-cl=%CLANG_DIR%\bin\clang-cl.exe
-    echo ##vso[task.setvariable variable=RUST_CONFIGURE_ARGS]%RUST_CONFIGURE_ARGS%
+# That installer was run through `wine` on Linux and then the resulting
+# installation directory (found in `$HOME/.wine/drive_c/Program Files/LLVM`) was
+# packaged up into a tarball. We've had issues otherwise that the installer will
+# randomly hang, provide not a lot of useful information, pollute global state,
+# etc. In general the tarball is just more confined and easier to deal with when
+# working with various CI environments.
+- bash: |
+    set -e
+    mkdir -p citools
+    cd citools
+    curl -f https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/LLVM-7.0.0-win64.tar.gz | tar xzf -
+    echo "##vso[task.setvariable variable=RUST_CONFIGURE_ARGS]$RUST_CONFIGURE_ARGS --set llvm.clang-cl=`pwd`/clang-rust/bin/clang-cl.exe"
   condition: and(succeeded(), eq(variables['Agent.OS'], 'Windows_NT'), eq(variables['MINGW_URL'],''))
   displayName: Install clang (Windows)
 

From bb9bf0ca9a9eaeb14e910ff23037c02c14cdb494 Mon Sep 17 00:00:00 2001
From: Vadim Kaushan <admin@disasm.info>
Date: Thu, 18 Jul 2019 18:37:23 +0300
Subject: [PATCH 03/40] Add riscv32i-unknown-none-elf target

---
 src/ci/docker/dist-various-1/Dockerfile       |  1 +
 src/librustc_target/spec/mod.rs               |  1 +
 .../spec/riscv32i_unknown_none_elf.rs         | 32 +++++++++++++++++++
 src/tools/build-manifest/src/main.rs          |  1 +
 4 files changed, 35 insertions(+)
 create mode 100644 src/librustc_target/spec/riscv32i_unknown_none_elf.rs

diff --git a/src/ci/docker/dist-various-1/Dockerfile b/src/ci/docker/dist-various-1/Dockerfile
index 5ab4be328a9f7..2a81de75a69b9 100644
--- a/src/ci/docker/dist-various-1/Dockerfile
+++ b/src/ci/docker/dist-various-1/Dockerfile
@@ -112,6 +112,7 @@ ENV TARGETS=$TARGETS,thumbv7em-none-eabihf
 ENV TARGETS=$TARGETS,thumbv8m.base-none-eabi
 ENV TARGETS=$TARGETS,thumbv8m.main-none-eabi
 ENV TARGETS=$TARGETS,thumbv8m.main-none-eabihf
+ENV TARGETS=$TARGETS,riscv32i-unknown-none-elf
 ENV TARGETS=$TARGETS,riscv32imc-unknown-none-elf
 ENV TARGETS=$TARGETS,riscv32imac-unknown-none-elf
 ENV TARGETS=$TARGETS,riscv64imac-unknown-none-elf
diff --git a/src/librustc_target/spec/mod.rs b/src/librustc_target/spec/mod.rs
index 1fdc9b015ba39..ac1e1ed962fdf 100644
--- a/src/librustc_target/spec/mod.rs
+++ b/src/librustc_target/spec/mod.rs
@@ -464,6 +464,7 @@ supported_targets! {
     ("aarch64-unknown-hermit", aarch64_unknown_hermit),
     ("x86_64-unknown-hermit", x86_64_unknown_hermit),
 
+    ("riscv32i-unknown-none-elf", riscv32i_unknown_none_elf),
     ("riscv32imc-unknown-none-elf", riscv32imc_unknown_none_elf),
     ("riscv32imac-unknown-none-elf", riscv32imac_unknown_none_elf),
     ("riscv64imac-unknown-none-elf", riscv64imac_unknown_none_elf),
diff --git a/src/librustc_target/spec/riscv32i_unknown_none_elf.rs b/src/librustc_target/spec/riscv32i_unknown_none_elf.rs
new file mode 100644
index 0000000000000..314778408f7e5
--- /dev/null
+++ b/src/librustc_target/spec/riscv32i_unknown_none_elf.rs
@@ -0,0 +1,32 @@
+use crate::spec::{LinkerFlavor, LldFlavor, PanicStrategy,
+           Target, TargetOptions, TargetResult};
+
+pub fn target() -> TargetResult {
+    Ok(Target {
+        data_layout: "e-m:e-p:32:32-i64:64-n32-S128".to_string(),
+        llvm_target: "riscv32".to_string(),
+        target_endian: "little".to_string(),
+        target_pointer_width: "32".to_string(),
+        target_c_int_width: "32".to_string(),
+        target_os: "none".to_string(),
+        target_env: String::new(),
+        target_vendor: "unknown".to_string(),
+        arch: "riscv32".to_string(),
+        linker_flavor: LinkerFlavor::Lld(LldFlavor::Ld),
+
+        options: TargetOptions {
+            linker: Some("rust-lld".to_string()),
+            cpu: "generic-rv32".to_string(),
+            max_atomic_width: None,
+            atomic_cas: false,
+            features: String::new(),
+            executables: true,
+            panic_strategy: PanicStrategy::Abort,
+            relocation_model: "static".to_string(),
+            emit_debug_gdb_scripts: false,
+            abi_blacklist: super::riscv_base::abi_blacklist(),
+            eliminate_frame_pointer: false,
+            .. Default::default()
+        },
+    })
+}
diff --git a/src/tools/build-manifest/src/main.rs b/src/tools/build-manifest/src/main.rs
index b6e087c3844fa..20176557bcbeb 100644
--- a/src/tools/build-manifest/src/main.rs
+++ b/src/tools/build-manifest/src/main.rs
@@ -92,6 +92,7 @@ static TARGETS: &[&str] = &[
     "powerpc-unknown-linux-gnu",
     "powerpc64-unknown-linux-gnu",
     "powerpc64le-unknown-linux-gnu",
+    "riscv32i-unknown-none-elf",
     "riscv32imc-unknown-none-elf",
     "riscv32imac-unknown-none-elf",
     "riscv64imac-unknown-none-elf",

From b9784b18c2d18dee7100529fd0cbadc8fa331a62 Mon Sep 17 00:00:00 2001
From: Nikita Popov <nikita.ppv@gmail.com>
Date: Sat, 20 Jul 2019 12:12:12 +0200
Subject: [PATCH 04/40] Don't link mcjit/interpreter LLVM components

---
 src/librustc_llvm/build.rs   | 13 +++----------
 src/rustllvm/PassWrapper.cpp |  2 --
 src/rustllvm/rustllvm.h      |  4 ----
 3 files changed, 3 insertions(+), 16 deletions(-)

diff --git a/src/librustc_llvm/build.rs b/src/librustc_llvm/build.rs
index 21fa872c8dadb..3def2d8232f63 100644
--- a/src/librustc_llvm/build.rs
+++ b/src/librustc_llvm/build.rs
@@ -71,7 +71,8 @@ fn main() {
 
     let mut optional_components =
         vec!["x86", "arm", "aarch64", "amdgpu", "mips", "powerpc",
-             "systemz", "jsbackend", "webassembly", "msp430", "sparc", "nvptx"];
+             "systemz", "jsbackend", "webassembly", "msp430", "sparc", "nvptx",
+             "hexagon"];
 
     let mut version_cmd = Command::new(&llvm_config);
     version_cmd.arg("--version");
@@ -82,27 +83,19 @@ fn main() {
         if let (Some(major), Some(minor)) = (parts.next(), parts.next()) {
             (major, minor)
         } else {
-            (3, 9)
+            (6, 0)
         };
 
-    if major > 3 {
-        optional_components.push("hexagon");
-    }
-
     if major > 6 {
         optional_components.push("riscv");
     }
 
-    // FIXME: surely we don't need all these components, right? Stuff like mcjit
-    //        or interpreter the compiler itself never uses.
     let required_components = &["ipo",
                                 "bitreader",
                                 "bitwriter",
                                 "linker",
                                 "asmparser",
-                                "mcjit",
                                 "lto",
-                                "interpreter",
                                 "instrumentation"];
 
     let components = output(Command::new(&llvm_config).arg("--components"));
diff --git a/src/rustllvm/PassWrapper.cpp b/src/rustllvm/PassWrapper.cpp
index 7d20086d9a22e..0cda3465dc093 100644
--- a/src/rustllvm/PassWrapper.cpp
+++ b/src/rustllvm/PassWrapper.cpp
@@ -26,8 +26,6 @@
 using namespace llvm;
 using namespace llvm::legacy;
 
-extern cl::opt<bool> EnableARMEHABI;
-
 typedef struct LLVMOpaquePass *LLVMPassRef;
 typedef struct LLVMOpaqueTargetMachine *LLVMTargetMachineRef;
 
diff --git a/src/rustllvm/rustllvm.h b/src/rustllvm/rustllvm.h
index a9d267cdb3175..c3f0d174d4b41 100644
--- a/src/rustllvm/rustllvm.h
+++ b/src/rustllvm/rustllvm.h
@@ -1,15 +1,11 @@
 #include "llvm-c/BitReader.h"
 #include "llvm-c/Core.h"
-#include "llvm-c/ExecutionEngine.h"
 #include "llvm-c/Object.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseSet.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/Analysis/Lint.h"
 #include "llvm/Analysis/Passes.h"
-#include "llvm/ExecutionEngine/ExecutionEngine.h"
-#include "llvm/ExecutionEngine/Interpreter.h"
-#include "llvm/ExecutionEngine/MCJIT.h"
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/InlineAsm.h"
 #include "llvm/IR/LLVMContext.h"

From c442dae5b89f175c2aa52877cb4f693b0f2b2ca6 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 11 Jun 2019 18:36:15 +0200
Subject: [PATCH 05/40] Ignore NLL migrate mode test in the Polonius
 compare-mode

This is test specific to the NLL migrate mode which is irrelevant to -Z polonius.
It can't currently be encoded depending on migrate-mode and NLL/Polonius mode, so the NLL compare-mode also ignores it.
---
 src/test/ui/borrowck/borrowck-migrate-to-nll.edition.stderr | 2 +-
 src/test/ui/borrowck/borrowck-migrate-to-nll.rs             | 1 +
 src/test/ui/borrowck/borrowck-migrate-to-nll.zflag.stderr   | 2 +-
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/test/ui/borrowck/borrowck-migrate-to-nll.edition.stderr b/src/test/ui/borrowck/borrowck-migrate-to-nll.edition.stderr
index 663164cfc2c1c..d97883ad47a50 100644
--- a/src/test/ui/borrowck/borrowck-migrate-to-nll.edition.stderr
+++ b/src/test/ui/borrowck/borrowck-migrate-to-nll.edition.stderr
@@ -1,5 +1,5 @@
 warning[E0507]: cannot move out of `foo` in pattern guard
-  --> $DIR/borrowck-migrate-to-nll.rs:25:18
+  --> $DIR/borrowck-migrate-to-nll.rs:26:18
    |
 LL |                 (|| { let bar = foo; bar.take() })();
    |                  ^^             ---
diff --git a/src/test/ui/borrowck/borrowck-migrate-to-nll.rs b/src/test/ui/borrowck/borrowck-migrate-to-nll.rs
index 5b7018df91931..a64df9df25948 100644
--- a/src/test/ui/borrowck/borrowck-migrate-to-nll.rs
+++ b/src/test/ui/borrowck/borrowck-migrate-to-nll.rs
@@ -10,6 +10,7 @@
 // just ignore it instead:
 
 // ignore-compare-mode-nll
+// ignore-compare-mode-polonius
 
 // revisions: zflag edition
 //[zflag]compile-flags: -Z borrowck=migrate
diff --git a/src/test/ui/borrowck/borrowck-migrate-to-nll.zflag.stderr b/src/test/ui/borrowck/borrowck-migrate-to-nll.zflag.stderr
index 663164cfc2c1c..d97883ad47a50 100644
--- a/src/test/ui/borrowck/borrowck-migrate-to-nll.zflag.stderr
+++ b/src/test/ui/borrowck/borrowck-migrate-to-nll.zflag.stderr
@@ -1,5 +1,5 @@
 warning[E0507]: cannot move out of `foo` in pattern guard
-  --> $DIR/borrowck-migrate-to-nll.rs:25:18
+  --> $DIR/borrowck-migrate-to-nll.rs:26:18
    |
 LL |                 (|| { let bar = foo; bar.take() })();
    |                  ^^             ---

From d4ca9a349ca67f3e23692a1ebfbce919da307738 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 11 Jun 2019 18:53:54 +0200
Subject: [PATCH 06/40] Ignore test issue-45983 in the polonius compare mode

There is no difference between the NLL and Polonius outputs, and it manually tests NLLs.
---
 src/test/ui/borrowck/issue-45983.migrate.stderr | 2 +-
 src/test/ui/borrowck/issue-45983.nll.stderr     | 4 ++--
 src/test/ui/borrowck/issue-45983.rs             | 1 +
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/test/ui/borrowck/issue-45983.migrate.stderr b/src/test/ui/borrowck/issue-45983.migrate.stderr
index 3a6b2f69a1ffc..c1564cf07e68a 100644
--- a/src/test/ui/borrowck/issue-45983.migrate.stderr
+++ b/src/test/ui/borrowck/issue-45983.migrate.stderr
@@ -1,5 +1,5 @@
 error: borrowed data cannot be stored outside of its closure
-  --> $DIR/issue-45983.rs:19:27
+  --> $DIR/issue-45983.rs:20:27
    |
 LL |     let x = None;
    |         - borrowed data cannot be stored into here...
diff --git a/src/test/ui/borrowck/issue-45983.nll.stderr b/src/test/ui/borrowck/issue-45983.nll.stderr
index 94360b65ffe36..dff0b4cebace9 100644
--- a/src/test/ui/borrowck/issue-45983.nll.stderr
+++ b/src/test/ui/borrowck/issue-45983.nll.stderr
@@ -1,5 +1,5 @@
 error[E0521]: borrowed data escapes outside of closure
-  --> $DIR/issue-45983.rs:19:18
+  --> $DIR/issue-45983.rs:20:18
    |
 LL |     let x = None;
    |         - `x` is declared here, outside of the closure body
@@ -9,7 +9,7 @@ LL |     give_any(|y| x = Some(y));
    |               `y` is a reference that is only valid in the closure body
 
 error[E0594]: cannot assign to `x`, as it is not declared as mutable
-  --> $DIR/issue-45983.rs:19:18
+  --> $DIR/issue-45983.rs:20:18
    |
 LL |     let x = None;
    |         - help: consider changing this to be mutable: `mut x`
diff --git a/src/test/ui/borrowck/issue-45983.rs b/src/test/ui/borrowck/issue-45983.rs
index a2656f5939aa1..3cd282077424b 100644
--- a/src/test/ui/borrowck/issue-45983.rs
+++ b/src/test/ui/borrowck/issue-45983.rs
@@ -7,6 +7,7 @@
 // revisions, don't worry about the --compare-mode=nll on this test.
 
 // ignore-compare-mode-nll
+// ignore-compare-mode-polonius
 
 //[nll]compile-flags: -Z borrowck=mir
 

From 273bfd43c1c1b315ef7996ac5ef4ca2a1f1ebd2f Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 11 Jun 2019 19:02:13 +0200
Subject: [PATCH 07/40] Ignore two-phase-reservation-sharing-interference-2.rs
 in Polonius compare mode

This is just a difference from the test construction, it's ignore-compare-mode-nll and manually checks migrate/nll over edition2015/2018.

This failure is because the `migrate2015` and `migrate2018`  revisions are ran with `-Zpolonius`. There is no actual difference in the errors output by NLLs and Polonius.
---
 ...se-reservation-sharing-interference-2.migrate2015.stderr | 6 +++---
 ...se-reservation-sharing-interference-2.migrate2018.stderr | 6 +++---
 ...-phase-reservation-sharing-interference-2.nll2015.stderr | 6 +++---
 ...-phase-reservation-sharing-interference-2.nll2018.stderr | 6 +++---
 .../two-phase-reservation-sharing-interference-2.rs         | 1 +
 5 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.migrate2015.stderr b/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.migrate2015.stderr
index 565e433f77361..88e9ced03ddde 100644
--- a/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.migrate2015.stderr
+++ b/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.migrate2015.stderr
@@ -1,5 +1,5 @@
 error[E0502]: cannot borrow `v` as mutable because it is also borrowed as immutable
-  --> $DIR/two-phase-reservation-sharing-interference-2.rs:18:5
+  --> $DIR/two-phase-reservation-sharing-interference-2.rs:19:5
    |
 LL |     let shared = &v;
    |                  -- immutable borrow occurs here
@@ -11,7 +11,7 @@ LL |     v.extend(shared);
    |     mutable borrow occurs here
 
 error[E0502]: cannot borrow `v` as mutable because it is also borrowed as immutable
-  --> $DIR/two-phase-reservation-sharing-interference-2.rs:28:5
+  --> $DIR/two-phase-reservation-sharing-interference-2.rs:29:5
    |
 LL |     v.extend(&v);
    |     ^^------^--^
@@ -21,7 +21,7 @@ LL |     v.extend(&v);
    |     mutable borrow occurs here
 
 warning: cannot borrow `v` as mutable because it is also borrowed as immutable
-  --> $DIR/two-phase-reservation-sharing-interference-2.rs:39:5
+  --> $DIR/two-phase-reservation-sharing-interference-2.rs:40:5
    |
 LL |     let shared = &v;
    |                  -- immutable borrow occurs here
diff --git a/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.migrate2018.stderr b/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.migrate2018.stderr
index 565e433f77361..88e9ced03ddde 100644
--- a/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.migrate2018.stderr
+++ b/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.migrate2018.stderr
@@ -1,5 +1,5 @@
 error[E0502]: cannot borrow `v` as mutable because it is also borrowed as immutable
-  --> $DIR/two-phase-reservation-sharing-interference-2.rs:18:5
+  --> $DIR/two-phase-reservation-sharing-interference-2.rs:19:5
    |
 LL |     let shared = &v;
    |                  -- immutable borrow occurs here
@@ -11,7 +11,7 @@ LL |     v.extend(shared);
    |     mutable borrow occurs here
 
 error[E0502]: cannot borrow `v` as mutable because it is also borrowed as immutable
-  --> $DIR/two-phase-reservation-sharing-interference-2.rs:28:5
+  --> $DIR/two-phase-reservation-sharing-interference-2.rs:29:5
    |
 LL |     v.extend(&v);
    |     ^^------^--^
@@ -21,7 +21,7 @@ LL |     v.extend(&v);
    |     mutable borrow occurs here
 
 warning: cannot borrow `v` as mutable because it is also borrowed as immutable
-  --> $DIR/two-phase-reservation-sharing-interference-2.rs:39:5
+  --> $DIR/two-phase-reservation-sharing-interference-2.rs:40:5
    |
 LL |     let shared = &v;
    |                  -- immutable borrow occurs here
diff --git a/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.nll2015.stderr b/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.nll2015.stderr
index 730741c7a9ae2..52017394e898e 100644
--- a/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.nll2015.stderr
+++ b/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.nll2015.stderr
@@ -1,5 +1,5 @@
 error[E0502]: cannot borrow `v` as mutable because it is also borrowed as immutable
-  --> $DIR/two-phase-reservation-sharing-interference-2.rs:18:5
+  --> $DIR/two-phase-reservation-sharing-interference-2.rs:19:5
    |
 LL |     let shared = &v;
    |                  -- immutable borrow occurs here
@@ -10,7 +10,7 @@ LL |     v.extend(shared);
    |     mutable borrow occurs here
 
 error[E0502]: cannot borrow `v` as mutable because it is also borrowed as immutable
-  --> $DIR/two-phase-reservation-sharing-interference-2.rs:28:5
+  --> $DIR/two-phase-reservation-sharing-interference-2.rs:29:5
    |
 LL |     v.extend(&v);
    |     ^^------^--^
@@ -20,7 +20,7 @@ LL |     v.extend(&v);
    |     mutable borrow occurs here
 
 error[E0502]: cannot borrow `v` as mutable because it is also borrowed as immutable
-  --> $DIR/two-phase-reservation-sharing-interference-2.rs:39:5
+  --> $DIR/two-phase-reservation-sharing-interference-2.rs:40:5
    |
 LL |     let shared = &v;
    |                  -- immutable borrow occurs here
diff --git a/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.nll2018.stderr b/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.nll2018.stderr
index 730741c7a9ae2..52017394e898e 100644
--- a/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.nll2018.stderr
+++ b/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.nll2018.stderr
@@ -1,5 +1,5 @@
 error[E0502]: cannot borrow `v` as mutable because it is also borrowed as immutable
-  --> $DIR/two-phase-reservation-sharing-interference-2.rs:18:5
+  --> $DIR/two-phase-reservation-sharing-interference-2.rs:19:5
    |
 LL |     let shared = &v;
    |                  -- immutable borrow occurs here
@@ -10,7 +10,7 @@ LL |     v.extend(shared);
    |     mutable borrow occurs here
 
 error[E0502]: cannot borrow `v` as mutable because it is also borrowed as immutable
-  --> $DIR/two-phase-reservation-sharing-interference-2.rs:28:5
+  --> $DIR/two-phase-reservation-sharing-interference-2.rs:29:5
    |
 LL |     v.extend(&v);
    |     ^^------^--^
@@ -20,7 +20,7 @@ LL |     v.extend(&v);
    |     mutable borrow occurs here
 
 error[E0502]: cannot borrow `v` as mutable because it is also borrowed as immutable
-  --> $DIR/two-phase-reservation-sharing-interference-2.rs:39:5
+  --> $DIR/two-phase-reservation-sharing-interference-2.rs:40:5
    |
 LL |     let shared = &v;
    |                  -- immutable borrow occurs here
diff --git a/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.rs b/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.rs
index de1af3aaa05e4..14f687c23780c 100644
--- a/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.rs
+++ b/src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.rs
@@ -3,6 +3,7 @@
 // everyone else.
 
 //ignore-compare-mode-nll
+//ignore-compare-mode-polonius
 
 //revisions: migrate2015 migrate2018 nll2015 nll2018
 

From 63c837ef8db1e7452a6ef2faf2660d8038ed5ad5 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 11 Jun 2019 19:08:56 +0200
Subject: [PATCH 08/40] Ignore feature-gate-nll.rs in Polonius compare mode

This is a test about turning the NLL feature gate on, ignored by the NLL compare-mode.
---
 src/test/ui/feature-gates/feature-gate-nll.rs     | 1 +
 src/test/ui/feature-gates/feature-gate-nll.stderr | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/test/ui/feature-gates/feature-gate-nll.rs b/src/test/ui/feature-gates/feature-gate-nll.rs
index ec5eacd162547..8ec752409ab00 100644
--- a/src/test/ui/feature-gates/feature-gate-nll.rs
+++ b/src/test/ui/feature-gates/feature-gate-nll.rs
@@ -3,6 +3,7 @@
 
 // Don't use compare-mode=nll, since that turns on NLL.
 // ignore-compare-mode-nll
+// ignore-compare-mode-polonius
 
 #![feature(rustc_attrs)]
 
diff --git a/src/test/ui/feature-gates/feature-gate-nll.stderr b/src/test/ui/feature-gates/feature-gate-nll.stderr
index 37542d52dc2ce..e5b28bbfa2477 100644
--- a/src/test/ui/feature-gates/feature-gate-nll.stderr
+++ b/src/test/ui/feature-gates/feature-gate-nll.stderr
@@ -1,5 +1,5 @@
 warning[E0502]: cannot borrow `*x.1` as immutable because it is also borrowed as mutable
-  --> $DIR/feature-gate-nll.rs:14:13
+  --> $DIR/feature-gate-nll.rs:15:13
    |
 LL |     let m = &mut x;
    |             ------ mutable borrow occurs here
@@ -14,7 +14,7 @@ LL |     m;
    = note: for more information, try `rustc --explain E0729`
 
 error: compilation successful
-  --> $DIR/feature-gate-nll.rs:10:1
+  --> $DIR/feature-gate-nll.rs:11:1
    |
 LL | / fn main() {
 LL | |     let mut x = (33, &0);

From 51c15fae61cdf3af53a127b0c062fdacd596ebea Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 11 Jun 2019 19:12:45 +0200
Subject: [PATCH 09/40] Ignore test issue-45696-scribble-on-boxed-borrow.rs in
 Polonius compare mode

Once again, the difference is in the test construction, it is ignored in compare-mode NLL and tested manually with revisions, and fails because the `migrate` revision is ran with `-Zpolonius`. There is no actual difference in the errors output by NLLs and Polonius.
---
 .../issue-45696-scribble-on-boxed-borrow.migrate.stderr   | 8 ++++----
 .../issue-45696-scribble-on-boxed-borrow.nll.stderr       | 6 +++---
 .../ui/issues/issue-45696-scribble-on-boxed-borrow.rs     | 1 +
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.migrate.stderr b/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.migrate.stderr
index 479b724ad18f1..2e99572d01828 100644
--- a/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.migrate.stderr
+++ b/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.migrate.stderr
@@ -1,5 +1,5 @@
 warning[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:51:5
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:52:5
    |
 LL | fn scribbled<'a>(s: Scribble<'a>) -> &'a mut u32 {
    |              -- lifetime `'a` defined here
@@ -14,7 +14,7 @@ LL | }
    = note: for more information, try `rustc --explain E0729`
 
 warning[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:62:5
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:63:5
    |
 LL | fn boxed_scribbled<'a>(s: Box<Scribble<'a>>) -> &'a mut u32 {
    |                    -- lifetime `'a` defined here
@@ -29,7 +29,7 @@ LL | }
    = note: for more information, try `rustc --explain E0729`
 
 warning[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:73:5
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:74:5
    |
 LL | fn boxed_boxed_scribbled<'a>(s: Box<Box<Scribble<'a>>>) -> &'a mut u32 {
    |                          -- lifetime `'a` defined here
@@ -44,7 +44,7 @@ LL | }
    = note: for more information, try `rustc --explain E0729`
 
 error: compilation successful
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:80:1
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:81:1
    |
 LL | / fn main() {
 LL | |     let mut x = 1;
diff --git a/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.nll.stderr b/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.nll.stderr
index 1b9fb0499260c..45b22511d27d6 100644
--- a/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.nll.stderr
+++ b/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.nll.stderr
@@ -1,5 +1,5 @@
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:51:5
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:52:5
    |
 LL | fn scribbled<'a>(s: Scribble<'a>) -> &'a mut u32 {
    |              -- lifetime `'a` defined here
@@ -10,7 +10,7 @@ LL | }
    | - here, drop of `s` needs exclusive access to `*s.0`, because the type `Scribble<'_>` implements the `Drop` trait
 
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:62:5
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:63:5
    |
 LL | fn boxed_scribbled<'a>(s: Box<Scribble<'a>>) -> &'a mut u32 {
    |                    -- lifetime `'a` defined here
@@ -21,7 +21,7 @@ LL | }
    | - here, drop of `s` needs exclusive access to `*s.0`, because the type `Scribble<'_>` implements the `Drop` trait
 
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:73:5
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:74:5
    |
 LL | fn boxed_boxed_scribbled<'a>(s: Box<Box<Scribble<'a>>>) -> &'a mut u32 {
    |                          -- lifetime `'a` defined here
diff --git a/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.rs b/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.rs
index f568efa487cd7..9f261884f3d2d 100644
--- a/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.rs
+++ b/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.rs
@@ -7,6 +7,7 @@
 
 // revisions: nll migrate
 // ignore-compare-mode-nll
+// ignore-compare-mode-polonius
 
 // This test is going to pass in the migrate revision, because the AST-borrowck
 // accepted this code in the past (see notes below). So we use `#[rustc_error]`

From ff350f8efa1882c34a2d4e2d48b1fed62b2fae31 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 11 Jun 2019 19:21:24 +0200
Subject: [PATCH 10/40] Bless output of test ui/emit-artifact-notifications.rs
 for Polonius

---
 src/test/ui/emit-artifact-notifications.polonius.stderr | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 src/test/ui/emit-artifact-notifications.polonius.stderr

diff --git a/src/test/ui/emit-artifact-notifications.polonius.stderr b/src/test/ui/emit-artifact-notifications.polonius.stderr
new file mode 100644
index 0000000000000..47b48b399c25c
--- /dev/null
+++ b/src/test/ui/emit-artifact-notifications.polonius.stderr
@@ -0,0 +1 @@
+{"artifact":"$TEST_BUILD_DIR/emit-artifact-notifications.polonius/libemit_artifact_notifications.rmeta","emit":"metadata"}

From 2824db1388dbd300c80466b10dc736d2780b8000 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 11 Jun 2019 19:24:50 +0200
Subject: [PATCH 11/40] Bless output of test
 save-analysis/emit-notifications.rs for Polonius

---
 src/test/ui/save-analysis/emit-notifications.polonius.stderr | 2 ++
 1 file changed, 2 insertions(+)
 create mode 100644 src/test/ui/save-analysis/emit-notifications.polonius.stderr

diff --git a/src/test/ui/save-analysis/emit-notifications.polonius.stderr b/src/test/ui/save-analysis/emit-notifications.polonius.stderr
new file mode 100644
index 0000000000000..a1a1b8c63dac3
--- /dev/null
+++ b/src/test/ui/save-analysis/emit-notifications.polonius.stderr
@@ -0,0 +1,2 @@
+{"artifact":"$TEST_BUILD_DIR/save-analysis/emit-notifications.polonius/save-analysis/libemit_notifications.json","emit":"save-analysis"}
+{"artifact":"$TEST_BUILD_DIR/save-analysis/emit-notifications.polonius/libemit_notifications.rlib","emit":"link"}

From 94101046ffe4e6a01819631d00d3802a838af98a Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 11 Jun 2019 19:33:36 +0200
Subject: [PATCH 12/40] Bless output of test nll/loan_ends_mid_block_pair.rs
 for Polonius

---
 .../loan_ends_mid_block_pair.polonius.stderr  | 38 +++++++++++++++++++
 1 file changed, 38 insertions(+)
 create mode 100644 src/test/ui/nll/loan_ends_mid_block_pair.polonius.stderr

diff --git a/src/test/ui/nll/loan_ends_mid_block_pair.polonius.stderr b/src/test/ui/nll/loan_ends_mid_block_pair.polonius.stderr
new file mode 100644
index 0000000000000..c9537d42c41af
--- /dev/null
+++ b/src/test/ui/nll/loan_ends_mid_block_pair.polonius.stderr
@@ -0,0 +1,38 @@
+error[E0506]: cannot assign to `data.0` because it is borrowed
+  --> $DIR/loan_ends_mid_block_pair.rs:12:5
+   |
+LL |     let c = &mut data.0;
+   |             ----------- borrow of `data.0` occurs here
+LL |     capitalize(c);
+LL |     data.0 = 'e';
+   |     ^^^^^^^^^^^^ assignment to borrowed `data.0` occurs here
+...
+LL |     capitalize(c);
+   |                - borrow later used here
+
+error[E0506]: cannot assign to `data.0` because it is borrowed
+  --> $DIR/loan_ends_mid_block_pair.rs:14:5
+   |
+LL |     let c = &mut data.0;
+   |             ----------- borrow of `data.0` occurs here
+...
+LL |     data.0 = 'f';
+   |     ^^^^^^^^^^^^ assignment to borrowed `data.0` occurs here
+LL |     data.0 = 'g';
+LL |     capitalize(c);
+   |                - borrow later used here
+
+error[E0506]: cannot assign to `data.0` because it is borrowed
+  --> $DIR/loan_ends_mid_block_pair.rs:15:5
+   |
+LL |     let c = &mut data.0;
+   |             ----------- borrow of `data.0` occurs here
+...
+LL |     data.0 = 'g';
+   |     ^^^^^^^^^^^^ assignment to borrowed `data.0` occurs here
+LL |     capitalize(c);
+   |                - borrow later used here
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0506`.

From 6a7c15ed25c17dfae87cc8561e7171ab749377e3 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Wed, 12 Jun 2019 12:55:18 +0200
Subject: [PATCH 13/40] Bless output of test consts/promote_const_let.rs for
 Polonius

---
 .../consts/promote_const_let.polonius.stderr  | 29 +++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 src/test/ui/consts/promote_const_let.polonius.stderr

diff --git a/src/test/ui/consts/promote_const_let.polonius.stderr b/src/test/ui/consts/promote_const_let.polonius.stderr
new file mode 100644
index 0000000000000..cf41bd7bdb1eb
--- /dev/null
+++ b/src/test/ui/consts/promote_const_let.polonius.stderr
@@ -0,0 +1,29 @@
+error[E0597]: `y` does not live long enough
+  --> $DIR/promote_const_let.rs:4:9
+   |
+LL |     let x: &'static u32 = {
+   |         - borrow later stored here
+LL |         let y = 42;
+LL |         &y
+   |         ^^ borrowed value does not live long enough
+LL |     };
+   |     - `y` dropped here while still borrowed
+
+error[E0716]: temporary value dropped while borrowed
+  --> $DIR/promote_const_let.rs:6:28
+   |
+LL |       let x: &'static u32 = &{
+   |  ____________------------____^
+   | |            |
+   | |            type annotation requires that borrow lasts for `'static`
+LL | |         let y = 42;
+LL | |         y
+LL | |     };
+   | |_____^ creates a temporary which is freed while still in use
+LL |   }
+   |   - temporary value is freed at the end of this statement
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0597, E0716.
+For more information about an error, try `rustc --explain E0597`.

From c5a1bc1e5c45c507b247e92d33a35190257c6726 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Wed, 12 Jun 2019 13:01:26 +0200
Subject: [PATCH 14/40] Bless output of test nll/get_default.rs for Polonius

2 of the 3 errors are "fixed by Polonius" :tada:
---
 src/test/ui/nll/get_default.polonius.stderr | 15 +++++++++++++++
 1 file changed, 15 insertions(+)
 create mode 100644 src/test/ui/nll/get_default.polonius.stderr

diff --git a/src/test/ui/nll/get_default.polonius.stderr b/src/test/ui/nll/get_default.polonius.stderr
new file mode 100644
index 0000000000000..2df6d5d61fc46
--- /dev/null
+++ b/src/test/ui/nll/get_default.polonius.stderr
@@ -0,0 +1,15 @@
+error[E0502]: cannot borrow `*map` as mutable because it is also borrowed as immutable
+  --> $DIR/get_default.rs:32:17
+   |
+LL |         match map.get() {
+   |               --- immutable borrow occurs here
+LL |             Some(v) => {
+LL |                 map.set(String::new()); // Both AST and MIR error here
+   |                 ^^^ mutable borrow occurs here
+LL |
+LL |                 return v;
+   |                        - immutable borrow later used here
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0502`.

From 292d5c18c93df1a502a03f228e36c4c1da3d3f6b Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Wed, 12 Jun 2019 19:27:59 +0200
Subject: [PATCH 15/40] Bless output of test
 generator/ref-escapes-but-not-over-yield.rs for Polonius

---
 ...escapes-but-not-over-yield.polonius.stderr | 20 +++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 src/test/ui/generator/ref-escapes-but-not-over-yield.polonius.stderr

diff --git a/src/test/ui/generator/ref-escapes-but-not-over-yield.polonius.stderr b/src/test/ui/generator/ref-escapes-but-not-over-yield.polonius.stderr
new file mode 100644
index 0000000000000..530bf368f676e
--- /dev/null
+++ b/src/test/ui/generator/ref-escapes-but-not-over-yield.polonius.stderr
@@ -0,0 +1,20 @@
+error[E0597]: `b` does not live long enough
+  --> $DIR/ref-escapes-but-not-over-yield.rs:11:13
+   |
+LL |       let mut b = move || {
+   |  _________________-
+LL | |         yield();
+LL | |         let b = 5;
+LL | |         a = &b;
+   | |             ^^ borrowed value does not live long enough
+LL | |
+LL | |     };
+   | |     -
+   | |     |
+   | |     `b` dropped here while still borrowed
+   | |_____... and the borrow might be used here, when that temporary is dropped and runs the destructor for generator
+   |       a temporary with access to the borrow is created here ...
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0597`.

From 6fe52928a3dd9a69ebd6422a23aba879871026c4 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Fri, 28 Jun 2019 13:37:08 +0200
Subject: [PATCH 16/40] Bless output of test 
 borrowck/borrowck-escaping-closure-error-2.rs for Polonius

---
 ...owck-escaping-closure-error-2.polonius.stderr | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
 create mode 100644 src/test/ui/borrowck/borrowck-escaping-closure-error-2.polonius.stderr

diff --git a/src/test/ui/borrowck/borrowck-escaping-closure-error-2.polonius.stderr b/src/test/ui/borrowck/borrowck-escaping-closure-error-2.polonius.stderr
new file mode 100644
index 0000000000000..89af8764557ff
--- /dev/null
+++ b/src/test/ui/borrowck/borrowck-escaping-closure-error-2.polonius.stderr
@@ -0,0 +1,16 @@
+error[E0597]: `books` does not live long enough
+  --> $DIR/borrowck-escaping-closure-error-2.rs:11:17
+   |
+LL |     Box::new(|| books.push(4))
+   |     ------------^^^^^---------
+   |     |        |  |
+   |     |        |  borrowed value does not live long enough
+   |     |        value captured here
+   |     borrow later used here
+LL |
+LL | }
+   | - `books` dropped here while still borrowed
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0597`.

From 7db61e78c01b93cceb28cf87e69d5d6c0ca0b482 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Fri, 28 Jun 2019 14:21:48 +0200
Subject: [PATCH 17/40] Bless output of test
 borrowck/two-phase-surprise-no-conflict.rs for Polonius

---
 ...phase-surprise-no-conflict.polonius.stderr | 148 ++++++++++++++++++
 1 file changed, 148 insertions(+)
 create mode 100644 src/test/ui/borrowck/two-phase-surprise-no-conflict.polonius.stderr

diff --git a/src/test/ui/borrowck/two-phase-surprise-no-conflict.polonius.stderr b/src/test/ui/borrowck/two-phase-surprise-no-conflict.polonius.stderr
new file mode 100644
index 0000000000000..7b246426a2333
--- /dev/null
+++ b/src/test/ui/borrowck/two-phase-surprise-no-conflict.polonius.stderr
@@ -0,0 +1,148 @@
+error[E0503]: cannot use `self.cx` because it was mutably borrowed
+  --> $DIR/two-phase-surprise-no-conflict.rs:21:23
+   |
+LL |         let _mut_borrow = &mut *self;
+   |                           ---------- borrow of `*self` occurs here
+LL |         let _access = self.cx;
+   |                       ^^^^^^^ use of borrowed `*self`
+LL |
+LL |         _mut_borrow;
+   |         ----------- borrow later used here
+
+error[E0502]: cannot borrow `*self` as mutable because it is also borrowed as immutable
+  --> $DIR/two-phase-surprise-no-conflict.rs:57:17
+   |
+LL |                 self.hash_expr(&self.cx_mut.body(eid).value);
+   |                 ^^^^^---------^^-----------^^^^^^^^^^^^^^^^^
+   |                 |    |          |
+   |                 |    |          immutable borrow occurs here
+   |                 |    immutable borrow later used by call
+   |                 mutable borrow occurs here
+
+error[E0499]: cannot borrow `reg.sess_mut` as mutable more than once at a time
+  --> $DIR/two-phase-surprise-no-conflict.rs:119:51
+   |
+LL |     reg.register_static(Box::new(TrivialPass::new(&mut reg.sess_mut)));
+   |     --- ---------------                           ^^^^^^^^^^^^^^^^^ second mutable borrow occurs here
+   |     |   |
+   |     |   first borrow later used by call
+   |     first mutable borrow occurs here
+
+error[E0499]: cannot borrow `reg.sess_mut` as mutable more than once at a time
+  --> $DIR/two-phase-surprise-no-conflict.rs:122:54
+   |
+LL |     reg.register_bound(Box::new(TrivialPass::new_mut(&mut reg.sess_mut)));
+   |     --- --------------                               ^^^^^^^^^^^^^^^^^ second mutable borrow occurs here
+   |     |   |
+   |     |   first borrow later used by call
+   |     first mutable borrow occurs here
+
+error[E0499]: cannot borrow `reg.sess_mut` as mutable more than once at a time
+  --> $DIR/two-phase-surprise-no-conflict.rs:125:53
+   |
+LL |     reg.register_univ(Box::new(TrivialPass::new_mut(&mut reg.sess_mut)));
+   |     --- -------------                               ^^^^^^^^^^^^^^^^^ second mutable borrow occurs here
+   |     |   |
+   |     |   first borrow later used by call
+   |     first mutable borrow occurs here
+
+error[E0499]: cannot borrow `reg.sess_mut` as mutable more than once at a time
+  --> $DIR/two-phase-surprise-no-conflict.rs:128:44
+   |
+LL |     reg.register_ref(&TrivialPass::new_mut(&mut reg.sess_mut));
+   |     --- ------------                       ^^^^^^^^^^^^^^^^^ second mutable borrow occurs here
+   |     |   |
+   |     |   first borrow later used by call
+   |     first mutable borrow occurs here
+
+error[E0502]: cannot borrow `*reg` as mutable because it is also borrowed as immutable
+  --> $DIR/two-phase-surprise-no-conflict.rs:138:5
+   |
+LL |     reg.register_bound(Box::new(CapturePass::new(&reg.sess_mut)));
+   |     ^^^^--------------^^^^^^^^^^^^^^^^^^^^^^^^^^^-------------^^^
+   |     |   |                                        |
+   |     |   |                                        immutable borrow occurs here
+   |     |   immutable borrow later used by call
+   |     mutable borrow occurs here
+
+error[E0502]: cannot borrow `*reg` as mutable because it is also borrowed as immutable
+  --> $DIR/two-phase-surprise-no-conflict.rs:141:5
+   |
+LL |     reg.register_univ(Box::new(CapturePass::new(&reg.sess_mut)));
+   |     ^^^^-------------^^^^^^^^^^^^^^^^^^^^^^^^^^^-------------^^^
+   |     |   |                                       |
+   |     |   |                                       immutable borrow occurs here
+   |     |   immutable borrow later used by call
+   |     mutable borrow occurs here
+
+error[E0502]: cannot borrow `*reg` as mutable because it is also borrowed as immutable
+  --> $DIR/two-phase-surprise-no-conflict.rs:144:5
+   |
+LL |     reg.register_ref(&CapturePass::new(&reg.sess_mut));
+   |     ^^^^------------^^^^^^^^^^^^^^^^^^^-------------^^
+   |     |   |                              |
+   |     |   |                              immutable borrow occurs here
+   |     |   immutable borrow later used by call
+   |     mutable borrow occurs here
+
+error[E0499]: cannot borrow `*reg` as mutable more than once at a time
+  --> $DIR/two-phase-surprise-no-conflict.rs:154:5
+   |
+LL |     reg.register_bound(Box::new(CapturePass::new_mut(&mut reg.sess_mut)));
+   |     ^^^^--------------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-----------------^^^
+   |     |   |                                            |
+   |     |   |                                            first mutable borrow occurs here
+   |     |   first borrow later used by call
+   |     second mutable borrow occurs here
+
+error[E0499]: cannot borrow `reg.sess_mut` as mutable more than once at a time
+  --> $DIR/two-phase-surprise-no-conflict.rs:154:54
+   |
+LL |     reg.register_bound(Box::new(CapturePass::new_mut(&mut reg.sess_mut)));
+   |     --- --------------                               ^^^^^^^^^^^^^^^^^ second mutable borrow occurs here
+   |     |   |
+   |     |   first borrow later used by call
+   |     first mutable borrow occurs here
+
+error[E0499]: cannot borrow `*reg` as mutable more than once at a time
+  --> $DIR/two-phase-surprise-no-conflict.rs:158:5
+   |
+LL |     reg.register_univ(Box::new(CapturePass::new_mut(&mut reg.sess_mut)));
+   |     ^^^^-------------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-----------------^^^
+   |     |   |                                           |
+   |     |   |                                           first mutable borrow occurs here
+   |     |   first borrow later used by call
+   |     second mutable borrow occurs here
+
+error[E0499]: cannot borrow `reg.sess_mut` as mutable more than once at a time
+  --> $DIR/two-phase-surprise-no-conflict.rs:158:53
+   |
+LL |     reg.register_univ(Box::new(CapturePass::new_mut(&mut reg.sess_mut)));
+   |     --- -------------                               ^^^^^^^^^^^^^^^^^ second mutable borrow occurs here
+   |     |   |
+   |     |   first borrow later used by call
+   |     first mutable borrow occurs here
+
+error[E0499]: cannot borrow `*reg` as mutable more than once at a time
+  --> $DIR/two-phase-surprise-no-conflict.rs:162:5
+   |
+LL |     reg.register_ref(&CapturePass::new_mut(&mut reg.sess_mut));
+   |     ^^^^------------^^^^^^^^^^^^^^^^^^^^^^^-----------------^^
+   |     |   |                                  |
+   |     |   |                                  first mutable borrow occurs here
+   |     |   first borrow later used by call
+   |     second mutable borrow occurs here
+
+error[E0499]: cannot borrow `reg.sess_mut` as mutable more than once at a time
+  --> $DIR/two-phase-surprise-no-conflict.rs:162:44
+   |
+LL |     reg.register_ref(&CapturePass::new_mut(&mut reg.sess_mut));
+   |     --- ------------                       ^^^^^^^^^^^^^^^^^ second mutable borrow occurs here
+   |     |   |
+   |     |   first borrow later used by call
+   |     first mutable borrow occurs here
+
+error: aborting due to 15 previous errors
+
+Some errors have detailed explanations: E0499, E0502, E0503.
+For more information about an error, try `rustc --explain E0499`.

From 08c25b5122574e1dca21c673cb6d2e7ceee489b1 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Fri, 28 Jun 2019 14:26:05 +0200
Subject: [PATCH 18/40] Bless output of test
 dropck/dropck_trait_cycle_checked.rs for Polonius

---
 ...dropck_trait_cycle_checked.polonius.stderr | 74 +++++++++++++++++++
 1 file changed, 74 insertions(+)
 create mode 100644 src/test/ui/dropck/dropck_trait_cycle_checked.polonius.stderr

diff --git a/src/test/ui/dropck/dropck_trait_cycle_checked.polonius.stderr b/src/test/ui/dropck/dropck_trait_cycle_checked.polonius.stderr
new file mode 100644
index 0000000000000..dbcb0fcebb73d
--- /dev/null
+++ b/src/test/ui/dropck/dropck_trait_cycle_checked.polonius.stderr
@@ -0,0 +1,74 @@
+error[E0597]: `o2` does not live long enough
+  --> $DIR/dropck_trait_cycle_checked.rs:111:13
+   |
+LL |     o1.set0(&o2);
+   |             ^^^ borrowed value does not live long enough
+...
+LL | }
+   | -
+   | |
+   | `o2` dropped here while still borrowed
+   | borrow might be used here, when `o2` is dropped and runs the destructor for type `std::boxed::Box<dyn Obj<'_>>`
+
+error[E0597]: `o3` does not live long enough
+  --> $DIR/dropck_trait_cycle_checked.rs:112:13
+   |
+LL |     o1.set1(&o3);
+   |             ^^^ borrowed value does not live long enough
+...
+LL | }
+   | -
+   | |
+   | `o3` dropped here while still borrowed
+   | borrow might be used here, when `o3` is dropped and runs the destructor for type `std::boxed::Box<dyn Obj<'_>>`
+
+error[E0597]: `o2` does not live long enough
+  --> $DIR/dropck_trait_cycle_checked.rs:113:13
+   |
+LL |     let (o1, o2, o3): (Box<dyn Obj>, Box<dyn Obj>, Box<dyn Obj>) = (O::new(), O::new(), O::new());
+   |                                                                               -------- cast requires that `o2` is borrowed for `'static`
+...
+LL |     o2.set0(&o2);
+   |             ^^^ borrowed value does not live long enough
+...
+LL | }
+   | - `o2` dropped here while still borrowed
+
+error[E0597]: `o3` does not live long enough
+  --> $DIR/dropck_trait_cycle_checked.rs:114:13
+   |
+LL |     let (o1, o2, o3): (Box<dyn Obj>, Box<dyn Obj>, Box<dyn Obj>) = (O::new(), O::new(), O::new());
+   |                                                                                         -------- cast requires that `o3` is borrowed for `'static`
+...
+LL |     o2.set1(&o3);
+   |             ^^^ borrowed value does not live long enough
+...
+LL | }
+   | - `o3` dropped here while still borrowed
+
+error[E0597]: `o1` does not live long enough
+  --> $DIR/dropck_trait_cycle_checked.rs:115:13
+   |
+LL |     o3.set0(&o1);
+   |             ^^^ borrowed value does not live long enough
+LL |     o3.set1(&o2);
+LL | }
+   | -
+   | |
+   | `o1` dropped here while still borrowed
+   | borrow might be used here, when `o1` is dropped and runs the destructor for type `std::boxed::Box<dyn Obj<'_>>`
+
+error[E0597]: `o2` does not live long enough
+  --> $DIR/dropck_trait_cycle_checked.rs:116:13
+   |
+LL |     let (o1, o2, o3): (Box<dyn Obj>, Box<dyn Obj>, Box<dyn Obj>) = (O::new(), O::new(), O::new());
+   |                                                                               -------- cast requires that `o2` is borrowed for `'static`
+...
+LL |     o3.set1(&o2);
+   |             ^^^ borrowed value does not live long enough
+LL | }
+   | - `o2` dropped here while still borrowed
+
+error: aborting due to 6 previous errors
+
+For more information about this error, try `rustc --explain E0597`.

From 9a82f52e59c39e3a101a51cc6902ab0064c61c6a Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Fri, 5 Jul 2019 19:18:36 +0200
Subject: [PATCH 19/40] Create a dedicated polonius test folder

---
 src/test/ui/nll/{ => polonius}/polonius-smoke-test.rs     | 0
 src/test/ui/nll/{ => polonius}/polonius-smoke-test.stderr | 0
 2 files changed, 0 insertions(+), 0 deletions(-)
 rename src/test/ui/nll/{ => polonius}/polonius-smoke-test.rs (100%)
 rename src/test/ui/nll/{ => polonius}/polonius-smoke-test.stderr (100%)

diff --git a/src/test/ui/nll/polonius-smoke-test.rs b/src/test/ui/nll/polonius/polonius-smoke-test.rs
similarity index 100%
rename from src/test/ui/nll/polonius-smoke-test.rs
rename to src/test/ui/nll/polonius/polonius-smoke-test.rs
diff --git a/src/test/ui/nll/polonius-smoke-test.stderr b/src/test/ui/nll/polonius/polonius-smoke-test.stderr
similarity index 100%
rename from src/test/ui/nll/polonius-smoke-test.stderr
rename to src/test/ui/nll/polonius/polonius-smoke-test.stderr

From 6d9a4f978313798a275a150ffd0f103609484ebd Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Mon, 15 Jul 2019 15:54:43 +0200
Subject: [PATCH 20/40] Polonius facts: kill loans on Call terminators and
 StorageDead

---
 .../borrow_check/nll/constraint_generation.rs | 74 +++++++++++++++----
 src/test/ui/nll/polonius/calls-kill-loans.rs  | 24 ++++++
 2 files changed, 82 insertions(+), 16 deletions(-)
 create mode 100644 src/test/ui/nll/polonius/calls-kill-loans.rs

diff --git a/src/librustc_mir/borrow_check/nll/constraint_generation.rs b/src/librustc_mir/borrow_check/nll/constraint_generation.rs
index 055568f0a27a2..25d0eaafc0049 100644
--- a/src/librustc_mir/borrow_check/nll/constraint_generation.rs
+++ b/src/librustc_mir/borrow_check/nll/constraint_generation.rs
@@ -6,8 +6,8 @@ use crate::borrow_check::nll::region_infer::values::LivenessValues;
 use rustc::infer::InferCtxt;
 use rustc::mir::visit::TyContext;
 use rustc::mir::visit::Visitor;
-use rustc::mir::{BasicBlock, BasicBlockData, Location, Body, Place, PlaceBase, Rvalue};
-use rustc::mir::{SourceInfo, Statement, Terminator};
+use rustc::mir::{BasicBlock, BasicBlockData, Location, Body, Place, PlaceBase, Rvalue, TerminatorKind};
+use rustc::mir::{Local, SourceInfo, Statement, StatementKind, Terminator};
 use rustc::mir::UserTypeProjection;
 use rustc::ty::fold::TypeFoldable;
 use rustc::ty::{self, ClosureSubsts, GeneratorSubsts, RegionVid, Ty};
@@ -114,6 +114,17 @@ impl<'cg, 'cx, 'tcx> Visitor<'tcx> for ConstraintGeneration<'cg, 'cx, 'tcx> {
                 self.location_table
                     .start_index(location.successor_within_block()),
             ));
+
+            // If there are borrows on this now dead local, we need to record them as `killed`.
+            if let StatementKind::StorageDead(ref local) = statement.kind {
+                record_killed_borrows_for_local(
+                    all_facts,
+                    self.borrow_set,
+                    self.location_table,
+                    local,
+                    location,
+                );
+            }
         }
 
         self.super_statement(statement, location);
@@ -127,20 +138,7 @@ impl<'cg, 'cx, 'tcx> Visitor<'tcx> for ConstraintGeneration<'cg, 'cx, 'tcx> {
     ) {
         // When we see `X = ...`, then kill borrows of
         // `(*X).foo` and so forth.
-        if let Some(all_facts) = self.all_facts {
-            if let Place {
-                base: PlaceBase::Local(temp),
-                projection: None,
-            } = place {
-                if let Some(borrow_indices) = self.borrow_set.local_map.get(temp) {
-                    all_facts.killed.reserve(borrow_indices.len());
-                    for &borrow_index in borrow_indices {
-                        let location_index = self.location_table.mid_index(location);
-                        all_facts.killed.push((borrow_index, location_index));
-                    }
-                }
-            }
-        }
+        self.record_killed_borrows_for_place(place, location);
 
         self.super_assign(place, rvalue, location);
     }
@@ -167,6 +165,14 @@ impl<'cg, 'cx, 'tcx> Visitor<'tcx> for ConstraintGeneration<'cg, 'cx, 'tcx> {
             }
         }
 
+        // A `Call` terminator's return value can be a local which has borrows,
+        // so we need to record those as `killed` as well.
+        if let TerminatorKind::Call { ref destination, .. } = terminator.kind {
+            if let Some((place, _)) = destination {
+                self.record_killed_borrows_for_place(place, location);
+            }
+        }
+
         self.super_terminator(terminator, location);
     }
 
@@ -201,4 +207,40 @@ impl<'cx, 'cg, 'tcx> ConstraintGeneration<'cx, 'cg, 'tcx> {
                 self.liveness_constraints.add_element(vid, location);
             });
     }
+
+    /// When recording facts for Polonius, records the borrows on the specified place
+    /// as `killed`. For example, when assigning to a local, or on a call's return destination.
+    fn record_killed_borrows_for_place(&mut self, place: &Place<'tcx>, location: Location) {
+        if let Some(all_facts) = self.all_facts {
+            if let Place {
+                base: PlaceBase::Local(local),
+                projection: None,
+            } = place {
+                record_killed_borrows_for_local(
+                    all_facts,
+                    self.borrow_set,
+                    self.location_table,
+                    local,
+                    location,
+                );
+            }
+        }
+    }
+}
+
+/// When recording facts for Polonius, records the borrows on the specified local as `killed`.
+fn record_killed_borrows_for_local(
+    all_facts: &mut AllFacts,
+    borrow_set: &BorrowSet<'_>,
+    location_table: &LocationTable,
+    local: &Local,
+    location: Location,
+) {
+    if let Some(borrow_indices) = borrow_set.local_map.get(local) {
+        all_facts.killed.reserve(borrow_indices.len());
+        for &borrow_index in borrow_indices {
+            let location_index = location_table.mid_index(location);
+            all_facts.killed.push((borrow_index, location_index));
+        }
+    }
 }
diff --git a/src/test/ui/nll/polonius/calls-kill-loans.rs b/src/test/ui/nll/polonius/calls-kill-loans.rs
new file mode 100644
index 0000000000000..3121571478893
--- /dev/null
+++ b/src/test/ui/nll/polonius/calls-kill-loans.rs
@@ -0,0 +1,24 @@
+// `Call` terminators can write to a local which has existing loans
+// and those need to be killed like a regular assignment to a local.
+// This is a simplified version of issue 47680, is correctly accepted
+// by NLL but was incorrectly rejected by Polonius because of these
+// missing `killed` facts.
+
+// build-pass
+// compile-flags: -Z borrowck=mir -Z polonius
+// ignore-compare-mode-nll
+
+struct Thing;
+
+impl Thing {
+    fn next(&mut self) -> &mut Self { unimplemented!() }
+}
+
+fn main() {
+    let mut temp = &mut Thing;
+
+    loop {
+        let v = temp.next();
+        temp = v; // accepted by NLL, was incorrectly rejected by Polonius
+    }
+}

From 0bd2b3235808e50f1568d89bb85e2ec6f8397e49 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Mon, 15 Jul 2019 18:04:41 +0200
Subject: [PATCH 21/40] Bless output of test 
 borrowck/promote-ref-mut-in-let-issue-46557.rs for Polonius

---
 ...ref-mut-in-let-issue-46557.polonius.stderr | 59 +++++++++++++++++++
 1 file changed, 59 insertions(+)
 create mode 100644 src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.polonius.stderr

diff --git a/src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.polonius.stderr b/src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.polonius.stderr
new file mode 100644
index 0000000000000..a5b2e8762746c
--- /dev/null
+++ b/src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.polonius.stderr
@@ -0,0 +1,59 @@
+error[E0716]: temporary value dropped while borrowed
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:5:21
+   |
+LL |     let ref mut x = 1234543;
+   |                     ^^^^^^^ creates a temporary which is freed while still in use
+LL |     x
+   |     - borrow later used here
+LL | }
+   | - temporary value is freed at the end of this statement
+   |
+   = note: consider using a `let` binding to create a longer lived value
+
+error[E0716]: temporary value dropped while borrowed
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:10:25
+   |
+LL |     let (ref mut x, ) = (1234543, );
+   |                         ^^^^^^^^^^^ creates a temporary which is freed while still in use
+LL |     x
+   |     - borrow later used here
+LL | }
+   | - temporary value is freed at the end of this statement
+   |
+   = note: consider using a `let` binding to create a longer lived value
+
+error[E0515]: cannot return value referencing temporary value
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:15:5
+   |
+LL |       match 1234543 {
+   |       ^     ------- temporary value created here
+   |  _____|
+   | |
+LL | |         ref mut x => x
+LL | |     }
+   | |_____^ returns a value referencing data owned by the current function
+
+error[E0515]: cannot return value referencing temporary value
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:21:5
+   |
+LL |       match (123443,) {
+   |       ^     --------- temporary value created here
+   |  _____|
+   | |
+LL | |         (ref mut x,) => x,
+LL | |     }
+   | |_____^ returns a value referencing data owned by the current function
+
+error[E0515]: cannot return reference to temporary value
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:27:5
+   |
+LL |     &mut 1234543
+   |     ^^^^^-------
+   |     |    |
+   |     |    temporary value created here
+   |     returns a reference to data owned by the current function
+
+error: aborting due to 5 previous errors
+
+Some errors have detailed explanations: E0515, E0716.
+For more information about an error, try `rustc --explain E0515`.

From ed1625f29eabb0659cd9799623922c86a2e4415b Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Mon, 15 Jul 2019 18:22:02 +0200
Subject: [PATCH 22/40] Ignore test hrtb/issue-30786.rs in Polonius compare
 mode

---
 src/test/ui/hrtb/issue-30786.migrate.stderr | 6 +++---
 src/test/ui/hrtb/issue-30786.nll.stderr     | 4 ++--
 src/test/ui/hrtb/issue-30786.rs             | 1 +
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/src/test/ui/hrtb/issue-30786.migrate.stderr b/src/test/ui/hrtb/issue-30786.migrate.stderr
index 9a4f877282245..e7deca7644b0e 100644
--- a/src/test/ui/hrtb/issue-30786.migrate.stderr
+++ b/src/test/ui/hrtb/issue-30786.migrate.stderr
@@ -1,11 +1,11 @@
 error: implementation of `Stream` is not general enough
-  --> $DIR/issue-30786.rs:107:22
+  --> $DIR/issue-30786.rs:108:22
    |
 LL |     let map = source.map(|x: &_| x);
    |                      ^^^
    |
-   = note: `Stream` would have to be implemented for the type `&'0 mut Map<Repeat, [closure@$DIR/issue-30786.rs:107:26: 107:35]>`, for any lifetime `'0`
-   = note: but `Stream` is actually implemented for the type `&'1 mut Map<Repeat, [closure@$DIR/issue-30786.rs:107:26: 107:35]>`, for some specific lifetime `'1`
+   = note: `Stream` would have to be implemented for the type `&'0 mut Map<Repeat, [closure@$DIR/issue-30786.rs:108:26: 108:35]>`, for any lifetime `'0`
+   = note: but `Stream` is actually implemented for the type `&'1 mut Map<Repeat, [closure@$DIR/issue-30786.rs:108:26: 108:35]>`, for some specific lifetime `'1`
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/hrtb/issue-30786.nll.stderr b/src/test/ui/hrtb/issue-30786.nll.stderr
index 5c865d76851d3..8614d86d93ac3 100644
--- a/src/test/ui/hrtb/issue-30786.nll.stderr
+++ b/src/test/ui/hrtb/issue-30786.nll.stderr
@@ -1,11 +1,11 @@
 error: higher-ranked subtype error
-  --> $DIR/issue-30786.rs:111:18
+  --> $DIR/issue-30786.rs:112:18
    |
 LL |     let filter = map.filter(|x: &_| true);
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: higher-ranked subtype error
-  --> $DIR/issue-30786.rs:113:17
+  --> $DIR/issue-30786.rs:114:17
    |
 LL |     let count = filter.count(); // Assert that we still have a valid stream.
    |                 ^^^^^^^^^^^^^^
diff --git a/src/test/ui/hrtb/issue-30786.rs b/src/test/ui/hrtb/issue-30786.rs
index 321b83c3459d0..b9920a1950498 100644
--- a/src/test/ui/hrtb/issue-30786.rs
+++ b/src/test/ui/hrtb/issue-30786.rs
@@ -12,6 +12,7 @@
 // revisions, don't worry about the --compare-mode=nll on this test.
 
 // ignore-compare-mode-nll
+// ignore-compare-mode-polonius
 
 //[nll]compile-flags: -Z borrowck=mir
 

From 40e6b025b27892877935c96315920b382083fcce Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Mon, 15 Jul 2019 18:26:51 +0200
Subject: [PATCH 23/40] Bless output of test nll/return-ref-mut-issue-46557.rs
 for Polonius

---
 .../return-ref-mut-issue-46557.polonius.stderr    | 15 +++++++++++++++
 1 file changed, 15 insertions(+)
 create mode 100644 src/test/ui/nll/return-ref-mut-issue-46557.polonius.stderr

diff --git a/src/test/ui/nll/return-ref-mut-issue-46557.polonius.stderr b/src/test/ui/nll/return-ref-mut-issue-46557.polonius.stderr
new file mode 100644
index 0000000000000..8e3cf59cffb44
--- /dev/null
+++ b/src/test/ui/nll/return-ref-mut-issue-46557.polonius.stderr
@@ -0,0 +1,15 @@
+error[E0716]: temporary value dropped while borrowed
+  --> $DIR/return-ref-mut-issue-46557.rs:4:21
+   |
+LL |     let ref mut x = 1234543;
+   |                     ^^^^^^^ creates a temporary which is freed while still in use
+LL |     x
+   |     - borrow later used here
+LL | }
+   | - temporary value is freed at the end of this statement
+   |
+   = note: consider using a `let` binding to create a longer lived value
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0716`.

From 9bd9b0d9bf616e8a8e7f6b4c3580041b007dd868 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Mon, 15 Jul 2019 18:50:50 +0200
Subject: [PATCH 24/40] Add test extracted from rand, checking that StorageDead
 kills loans

Like "call-kills-loans", Polonius didn't know about some `killed` facts.
---
 .../nll/polonius/storagedead-kills-loans.rs   | 28 +++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 src/test/ui/nll/polonius/storagedead-kills-loans.rs

diff --git a/src/test/ui/nll/polonius/storagedead-kills-loans.rs b/src/test/ui/nll/polonius/storagedead-kills-loans.rs
new file mode 100644
index 0000000000000..3c121d3cd1882
--- /dev/null
+++ b/src/test/ui/nll/polonius/storagedead-kills-loans.rs
@@ -0,0 +1,28 @@
+// Whenever a `StorageDead` MIR statement destroys a value `x`,
+// we should kill all loans of `x`. This is extracted from `rand 0.4.6`,
+// is correctly accepted by NLL but was incorrectly rejected by
+// Polonius because of these missing `killed` facts.
+
+// build-pass
+// compile-flags: -Z borrowck=mir -Z polonius
+// ignore-compare-mode-nll
+
+use std::{io, mem};
+use std::io::Read;
+
+fn fill(r: &mut Read, mut buf: &mut [u8]) -> io::Result<()> {
+    while buf.len() > 0 {
+        match r.read(buf).unwrap() {
+            0 => return Err(io::Error::new(io::ErrorKind::Other,
+                                           "end of file reached")),
+            n => buf = &mut mem::replace(&mut buf, &mut [])[n..],
+            // ^- Polonius had multiple errors on the previous line (where NLL has none)
+            // as it didn't know `buf` was killed here, and would
+            // incorrectly reject both the borrow expression, and the assignment.
+        }
+    }
+    Ok(())
+}
+
+fn main() {
+}

From 606f7984e7fd0c33b6c7bd040dfd057569f1c19b Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Mon, 15 Jul 2019 18:51:55 +0200
Subject: [PATCH 25/40] Rename test so that both "kills-loans" tests match
 names

---
 .../nll/polonius/{calls-kill-loans.rs => call-kills-loans.rs}  | 0
 src/test/ui/nll/polonius/storagedead-kills-loans.rs            | 3 ++-
 2 files changed, 2 insertions(+), 1 deletion(-)
 rename src/test/ui/nll/polonius/{calls-kill-loans.rs => call-kills-loans.rs} (100%)

diff --git a/src/test/ui/nll/polonius/calls-kill-loans.rs b/src/test/ui/nll/polonius/call-kills-loans.rs
similarity index 100%
rename from src/test/ui/nll/polonius/calls-kill-loans.rs
rename to src/test/ui/nll/polonius/call-kills-loans.rs
diff --git a/src/test/ui/nll/polonius/storagedead-kills-loans.rs b/src/test/ui/nll/polonius/storagedead-kills-loans.rs
index 3c121d3cd1882..f69bfdf459320 100644
--- a/src/test/ui/nll/polonius/storagedead-kills-loans.rs
+++ b/src/test/ui/nll/polonius/storagedead-kills-loans.rs
@@ -10,7 +10,8 @@
 use std::{io, mem};
 use std::io::Read;
 
-fn fill(r: &mut Read, mut buf: &mut [u8]) -> io::Result<()> {
+#[allow(dead_code)]
+fn fill(r: &mut dyn Read, mut buf: &mut [u8]) -> io::Result<()> {
     while buf.len() > 0 {
         match r.read(buf).unwrap() {
             0 => return Err(io::Error::new(io::ErrorKind::Other,

From 9e0fb6fad256124354778783a135f3b0ac0553ee Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Mon, 15 Jul 2019 18:57:16 +0200
Subject: [PATCH 26/40] Make both polonius loans tests check-pass

---
 src/test/ui/nll/polonius/call-kills-loans.rs        | 2 +-
 src/test/ui/nll/polonius/storagedead-kills-loans.rs | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/test/ui/nll/polonius/call-kills-loans.rs b/src/test/ui/nll/polonius/call-kills-loans.rs
index 3121571478893..57dc140110246 100644
--- a/src/test/ui/nll/polonius/call-kills-loans.rs
+++ b/src/test/ui/nll/polonius/call-kills-loans.rs
@@ -4,7 +4,7 @@
 // by NLL but was incorrectly rejected by Polonius because of these
 // missing `killed` facts.
 
-// build-pass
+// check-pass
 // compile-flags: -Z borrowck=mir -Z polonius
 // ignore-compare-mode-nll
 
diff --git a/src/test/ui/nll/polonius/storagedead-kills-loans.rs b/src/test/ui/nll/polonius/storagedead-kills-loans.rs
index f69bfdf459320..ff801cbf9f35d 100644
--- a/src/test/ui/nll/polonius/storagedead-kills-loans.rs
+++ b/src/test/ui/nll/polonius/storagedead-kills-loans.rs
@@ -3,7 +3,7 @@
 // is correctly accepted by NLL but was incorrectly rejected by
 // Polonius because of these missing `killed` facts.
 
-// build-pass
+// check-pass
 // compile-flags: -Z borrowck=mir -Z polonius
 // ignore-compare-mode-nll
 

From 823ab42e66cc966098030616e36e4aa7417dcf7f Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Mon, 15 Jul 2019 19:04:50 +0200
Subject: [PATCH 27/40] Bless output of test
 unboxed-closures/unboxed-closures-failed-recursive-fn-1.rs for Polonius

---
 ...ures-failed-recursive-fn-1.polonius.stderr | 60 +++++++++++++++++++
 1 file changed, 60 insertions(+)
 create mode 100644 src/test/ui/unboxed-closures/unboxed-closures-failed-recursive-fn-1.polonius.stderr

diff --git a/src/test/ui/unboxed-closures/unboxed-closures-failed-recursive-fn-1.polonius.stderr b/src/test/ui/unboxed-closures/unboxed-closures-failed-recursive-fn-1.polonius.stderr
new file mode 100644
index 0000000000000..4b906f75149af
--- /dev/null
+++ b/src/test/ui/unboxed-closures/unboxed-closures-failed-recursive-fn-1.polonius.stderr
@@ -0,0 +1,60 @@
+error[E0597]: `factorial` does not live long enough
+  --> $DIR/unboxed-closures-failed-recursive-fn-1.rs:15:17
+   |
+LL |     let f = |x: u32| -> u32 {
+   |             --------------- value captured here
+LL |         let g = factorial.as_ref().unwrap();
+   |                 ^^^^^^^^^ borrowed value does not live long enough
+...
+LL | }
+   | -
+   | |
+   | `factorial` dropped here while still borrowed
+   | borrow might be used here, when `factorial` is dropped and runs the destructor for type `std::option::Option<std::boxed::Box<dyn std::ops::Fn(u32) -> u32>>`
+
+error[E0506]: cannot assign to `factorial` because it is borrowed
+  --> $DIR/unboxed-closures-failed-recursive-fn-1.rs:20:5
+   |
+LL |     let f = |x: u32| -> u32 {
+   |             --------------- borrow of `factorial` occurs here
+LL |         let g = factorial.as_ref().unwrap();
+   |                 --------- borrow occurs due to use in closure
+...
+LL |     factorial = Some(Box::new(f));
+   |     ^^^^^^^^^
+   |     |
+   |     assignment to borrowed `factorial` occurs here
+   |     borrow later used here
+
+error[E0597]: `factorial` does not live long enough
+  --> $DIR/unboxed-closures-failed-recursive-fn-1.rs:28:17
+   |
+LL |     let f = |x: u32| -> u32 {
+   |             --------------- value captured here
+LL |         let g = factorial.as_ref().unwrap();
+   |                 ^^^^^^^^^ borrowed value does not live long enough
+...
+LL | }
+   | -
+   | |
+   | `factorial` dropped here while still borrowed
+   | borrow might be used here, when `factorial` is dropped and runs the destructor for type `std::option::Option<std::boxed::Box<dyn std::ops::Fn(u32) -> u32>>`
+
+error[E0506]: cannot assign to `factorial` because it is borrowed
+  --> $DIR/unboxed-closures-failed-recursive-fn-1.rs:33:5
+   |
+LL |     let f = |x: u32| -> u32 {
+   |             --------------- borrow of `factorial` occurs here
+LL |         let g = factorial.as_ref().unwrap();
+   |                 --------- borrow occurs due to use in closure
+...
+LL |     factorial = Some(Box::new(f));
+   |     ^^^^^^^^^
+   |     |
+   |     assignment to borrowed `factorial` occurs here
+   |     borrow later used here
+
+error: aborting due to 4 previous errors
+
+Some errors have detailed explanations: E0506, E0597.
+For more information about an error, try `rustc --explain E0506`.

From 2f3e36f51a7055da3b55253edad7df594b0711d7 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 16 Jul 2019 17:30:41 +0200
Subject: [PATCH 28/40] Polonius: generate `killed` facts for assignments to
 projections

---
 .../borrow_check/nll/constraint_generation.rs | 89 ++++++++++++++++---
 1 file changed, 75 insertions(+), 14 deletions(-)

diff --git a/src/librustc_mir/borrow_check/nll/constraint_generation.rs b/src/librustc_mir/borrow_check/nll/constraint_generation.rs
index 25d0eaafc0049..95c3299693b68 100644
--- a/src/librustc_mir/borrow_check/nll/constraint_generation.rs
+++ b/src/librustc_mir/borrow_check/nll/constraint_generation.rs
@@ -3,12 +3,15 @@ use crate::borrow_check::location::LocationTable;
 use crate::borrow_check::nll::ToRegionVid;
 use crate::borrow_check::nll::facts::AllFacts;
 use crate::borrow_check::nll::region_infer::values::LivenessValues;
+use crate::borrow_check::places_conflict;
 use rustc::infer::InferCtxt;
 use rustc::mir::visit::TyContext;
 use rustc::mir::visit::Visitor;
-use rustc::mir::{BasicBlock, BasicBlockData, Location, Body, Place, PlaceBase, Rvalue, TerminatorKind};
-use rustc::mir::{Local, SourceInfo, Statement, StatementKind, Terminator};
-use rustc::mir::UserTypeProjection;
+use rustc::mir::{
+    BasicBlock, BasicBlockData, Body, Local, Location, Place, PlaceBase, Projection,
+    ProjectionElem, Rvalue, SourceInfo, Statement, StatementKind, Terminator, TerminatorKind,
+    UserTypeProjection,
+};
 use rustc::ty::fold::TypeFoldable;
 use rustc::ty::{self, ClosureSubsts, GeneratorSubsts, RegionVid, Ty};
 use rustc::ty::subst::SubstsRef;
@@ -27,6 +30,7 @@ pub(super) fn generate_constraints<'cx, 'tcx>(
         liveness_constraints,
         location_table,
         all_facts,
+        body,
     };
 
     for (bb, data) in body.basic_blocks().iter_enumerated() {
@@ -41,6 +45,7 @@ struct ConstraintGeneration<'cg, 'cx, 'tcx> {
     location_table: &'cg LocationTable,
     liveness_constraints: &'cg mut LivenessValues<RegionVid>,
     borrow_set: &'cg BorrowSet<'tcx>,
+    body: &'cg Body<'tcx>,
 }
 
 impl<'cg, 'cx, 'tcx> Visitor<'tcx> for ConstraintGeneration<'cg, 'cx, 'tcx> {
@@ -212,17 +217,73 @@ impl<'cx, 'cg, 'tcx> ConstraintGeneration<'cx, 'cg, 'tcx> {
     /// as `killed`. For example, when assigning to a local, or on a call's return destination.
     fn record_killed_borrows_for_place(&mut self, place: &Place<'tcx>, location: Location) {
         if let Some(all_facts) = self.all_facts {
-            if let Place {
-                base: PlaceBase::Local(local),
-                projection: None,
-            } = place {
-                record_killed_borrows_for_local(
-                    all_facts,
-                    self.borrow_set,
-                    self.location_table,
-                    local,
-                    location,
-                );
+            // Depending on the `Place` we're killing:
+            // - if it's a local, or a single deref of a local,
+            //   we kill all the borrows on the local.
+            // - if it's a deeper projection, we have to filter which
+            //   of the borrows are killed: the ones whose `borrowed_place`
+            //   conflicts with the `place`.
+            match place {
+                Place {
+                    base: PlaceBase::Local(local),
+                    projection: None,
+                } |
+                Place {
+                    base: PlaceBase::Local(local),
+                    projection: Some(box Projection {
+                        base: None,
+                        elem: ProjectionElem::Deref,
+                    }),
+                } => {
+                    debug!(
+                        "Recording `killed` facts for borrows of local={:?} at location={:?}",
+                        local, location
+                    );
+
+                    record_killed_borrows_for_local(
+                        all_facts,
+                        self.borrow_set,
+                        self.location_table,
+                        local,
+                        location,
+                    );
+                }
+
+                Place {
+                    base: PlaceBase::Static(_),
+                    ..
+                } => {
+                    // Ignore kills of static or static mut variables.
+                }
+
+                Place {
+                    base: PlaceBase::Local(local),
+                    projection: Some(_),
+                } => {
+                    // Kill conflicting borrows of the innermost local.
+                    debug!(
+                        "Recording `killed` facts for borrows of \
+                            innermost projected local={:?} at location={:?}",
+                        local, location
+                    );
+
+                    if let Some(borrow_indices) = self.borrow_set.local_map.get(local) {
+                        for &borrow_index in borrow_indices {
+                            let places_conflict = places_conflict::places_conflict(
+                                self.infcx.tcx,
+                                self.body,
+                                &self.borrow_set.borrows[borrow_index].borrowed_place,
+                                place,
+                                places_conflict::PlaceConflictBias::NoOverlap,
+                            );
+
+                            if places_conflict {
+                                let location_index = self.location_table.mid_index(location);
+                                all_facts.killed.push((borrow_index, location_index));
+                            }
+                        }
+                    }
+                }
             }
         }
     }

From d41e002111dd61efa08d996cfc1085fc00472288 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 16 Jul 2019 17:32:38 +0200
Subject: [PATCH 29/40] Add test checking various assignments are accepted in
 Polonius

---
 .../ui/nll/polonius/assignment-kills-loans.rs | 88 +++++++++++++++++++
 1 file changed, 88 insertions(+)
 create mode 100644 src/test/ui/nll/polonius/assignment-kills-loans.rs

diff --git a/src/test/ui/nll/polonius/assignment-kills-loans.rs b/src/test/ui/nll/polonius/assignment-kills-loans.rs
new file mode 100644
index 0000000000000..8301f603cb4d3
--- /dev/null
+++ b/src/test/ui/nll/polonius/assignment-kills-loans.rs
@@ -0,0 +1,88 @@
+#![allow(dead_code)]
+
+// This tests the various kinds of assignments there are. Polonius used to generate `killed`
+// facts only on simple assigments, but not projections, incorrectly causing errors to be emitted
+// for code accepted by NLL. They are all variations from example code in the NLL RFC.
+
+// check-pass
+// compile-flags: -Z borrowck=mir -Z polonius
+// ignore-compare-mode-nll
+
+struct List<T> {
+    value: T,
+    next: Option<Box<List<T>>>,
+}
+
+// Assignment to a local: the `list` assignment should clear the existing
+// borrows of `list.value` and `list.next`
+fn assignment_to_local<T>(mut list: &mut List<T>) -> Vec<&mut T> {
+    let mut result = vec![];
+    loop {
+        result.push(&mut list.value);
+        if let Some(n) = list.next.as_mut() {
+            list = n;
+        } else {
+            return result;
+        }
+    }
+}
+
+// Assignment to a deref projection: the `*list` assignment should clear the existing
+// borrows of `list.value` and `list.next`
+fn assignment_to_deref_projection<T>(mut list: Box<&mut List<T>>) -> Vec<&mut T> {
+    let mut result = vec![];
+    loop {
+        result.push(&mut list.value);
+        if let Some(n) = list.next.as_mut() {
+            *list = n;
+        } else {
+            return result;
+        }
+    }
+}
+
+// Assignment to a field projection: the `list.0` assignment should clear the existing
+// borrows of `list.0.value` and `list.0.next`
+fn assignment_to_field_projection<T>(mut list: (&mut List<T>,)) -> Vec<&mut T> {
+    let mut result = vec![];
+    loop {
+        result.push(&mut list.0.value);
+        if let Some(n) = list.0.next.as_mut() {
+            list.0 = n;
+        } else {
+            return result;
+        }
+    }
+}
+
+// Assignment to a deref field projection: the `*list.0` assignment should clear the existing
+// borrows of `list.0.value` and `list.0.next`
+fn assignment_to_deref_field_projection<T>(mut list: (Box<&mut List<T>>,)) -> Vec<&mut T> {
+    let mut result = vec![];
+    loop {
+        result.push(&mut list.0.value);
+        if let Some(n) = list.0.next.as_mut() {
+            *list.0 = n;
+        } else {
+            return result;
+        }
+    }
+}
+
+// Similar to `assignment_to_deref_field_projection` but through a longer projection chain
+fn assignment_through_projection_chain<T>(
+    mut list: (((((Box<&mut List<T>>,),),),),),
+) -> Vec<&mut T> {
+    let mut result = vec![];
+    loop {
+        result.push(&mut ((((list.0).0).0).0).0.value);
+        if let Some(n) = ((((list.0).0).0).0).0.next.as_mut() {
+            *((((list.0).0).0).0).0 = n;
+        } else {
+            return result;
+        }
+    }
+}
+
+fn main() {
+}
\ No newline at end of file

From 770129c28039ab7501cdc0f2f7ca1a38e22208f0 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 16 Jul 2019 17:33:16 +0200
Subject: [PATCH 30/40] Add test to check that assignments to projections do
 not kill too many loans

---
 .../polonius/assignment-to-differing-field.rs | 50 ++++++++++++++++++
 .../assignment-to-differing-field.stderr      | 51 +++++++++++++++++++
 2 files changed, 101 insertions(+)
 create mode 100644 src/test/ui/nll/polonius/assignment-to-differing-field.rs
 create mode 100644 src/test/ui/nll/polonius/assignment-to-differing-field.stderr

diff --git a/src/test/ui/nll/polonius/assignment-to-differing-field.rs b/src/test/ui/nll/polonius/assignment-to-differing-field.rs
new file mode 100644
index 0000000000000..c0ba1b983fc35
--- /dev/null
+++ b/src/test/ui/nll/polonius/assignment-to-differing-field.rs
@@ -0,0 +1,50 @@
+#![allow(dead_code)]
+
+// Compared to `assignment-kills-loans.rs`, we check here
+// that we do not kill too many borrows. Assignments to the `.1`
+// field projections should leave the borrows on `.0` intact.
+
+// compile-flags: -Z borrowck=mir -Z polonius
+// ignore-compare-mode-nll
+
+struct List<T> {
+    value: T,
+    next: Option<Box<List<T>>>,
+}
+
+
+fn assignment_to_field_projection<'a, T>(
+    mut list: (&'a mut List<T>, &'a mut List<T>),
+) -> Vec<&'a mut T> {
+    let mut result = vec![];
+    loop {
+        result.push(&mut (list.0).value);
+        //~^ ERROR cannot borrow `list.0.value` as mutable
+
+        if let Some(n) = (list.0).next.as_mut() {
+        //~^ ERROR cannot borrow `list.0.next` as mutable
+            list.1 = n;
+        } else {
+            return result;
+        }
+    }
+}
+
+fn assignment_through_projection_chain<'a, T>(
+    mut list: (((((Box<&'a mut List<T>>, Box<&'a mut List<T>>),),),),),
+) -> Vec<&'a mut T> {
+    let mut result = vec![];
+    loop {
+        result.push(&mut ((((list.0).0).0).0).0.value);
+        //~^ ERROR cannot borrow `list.0.0.0.0.0.value` as mutable
+
+        if let Some(n) = ((((list.0).0).0).0).0.next.as_mut() {
+        //~^ ERROR cannot borrow `list.0.0.0.0.0.next` as mutable
+            *((((list.0).0).0).0).1 = n;
+        } else {
+            return result;
+        }
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/nll/polonius/assignment-to-differing-field.stderr b/src/test/ui/nll/polonius/assignment-to-differing-field.stderr
new file mode 100644
index 0000000000000..07ca021b53bce
--- /dev/null
+++ b/src/test/ui/nll/polonius/assignment-to-differing-field.stderr
@@ -0,0 +1,51 @@
+error[E0499]: cannot borrow `list.0.value` as mutable more than once at a time
+  --> $DIR/assignment-to-differing-field.rs:21:21
+   |
+LL | fn assignment_to_field_projection<'a, T>(
+   |                                   -- lifetime `'a` defined here
+...
+LL |         result.push(&mut (list.0).value);
+   |                     ^^^^^^^^^^^^^^^^^^^ mutable borrow starts here in previous iteration of loop
+...
+LL |             return result;
+   |                    ------ returning this value requires that `list.0.value` is borrowed for `'a`
+
+error[E0499]: cannot borrow `list.0.next` as mutable more than once at a time
+  --> $DIR/assignment-to-differing-field.rs:24:26
+   |
+LL | fn assignment_to_field_projection<'a, T>(
+   |                                   -- lifetime `'a` defined here
+...
+LL |         if let Some(n) = (list.0).next.as_mut() {
+   |                          ^^^^^^^^^^^^^---------
+   |                          |
+   |                          mutable borrow starts here in previous iteration of loop
+   |                          argument requires that `list.0.next` is borrowed for `'a`
+
+error[E0499]: cannot borrow `list.0.0.0.0.0.value` as mutable more than once at a time
+  --> $DIR/assignment-to-differing-field.rs:38:21
+   |
+LL | fn assignment_through_projection_chain<'a, T>(
+   |                                        -- lifetime `'a` defined here
+...
+LL |         result.push(&mut ((((list.0).0).0).0).0.value);
+   |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ mutable borrow starts here in previous iteration of loop
+...
+LL |             return result;
+   |                    ------ returning this value requires that `list.0.0.0.0.0.value` is borrowed for `'a`
+
+error[E0499]: cannot borrow `list.0.0.0.0.0.next` as mutable more than once at a time
+  --> $DIR/assignment-to-differing-field.rs:41:26
+   |
+LL | fn assignment_through_projection_chain<'a, T>(
+   |                                        -- lifetime `'a` defined here
+...
+LL |         if let Some(n) = ((((list.0).0).0).0).0.next.as_mut() {
+   |                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^---------
+   |                          |
+   |                          mutable borrow starts here in previous iteration of loop
+   |                          argument requires that `list.0.0.0.0.0.next` is borrowed for `'a`
+
+error: aborting due to 4 previous errors
+
+For more information about this error, try `rustc --explain E0499`.

From c7f9a71d7875e5acced7f3a1b9f05a46be2104f4 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 16 Jul 2019 17:34:06 +0200
Subject: [PATCH 31/40] issue-46589 passes in Polonius and fails in NLL,
 duplicate it and manually check each outcome

---
 src/test/ui/nll/issue-46589.rs          |  6 +++++
 src/test/ui/nll/issue-46589.stderr      |  2 +-
 src/test/ui/nll/polonius/issue-46589.rs | 32 +++++++++++++++++++++++++
 3 files changed, 39 insertions(+), 1 deletion(-)
 create mode 100644 src/test/ui/nll/polonius/issue-46589.rs

diff --git a/src/test/ui/nll/issue-46589.rs b/src/test/ui/nll/issue-46589.rs
index 8c0c356e96721..0a4c20d15159f 100644
--- a/src/test/ui/nll/issue-46589.rs
+++ b/src/test/ui/nll/issue-46589.rs
@@ -1,3 +1,9 @@
+// This tests passes in Polonius mode, so is skipped in the automated compare-mode.
+// We will manually check it passes in Polonius tests, as we can't have a test here
+// which conditionally passes depending on a test revision/compile-flags.
+
+// ignore-compare-mode-polonius
+
 struct Foo;
 
 impl Foo {
diff --git a/src/test/ui/nll/issue-46589.stderr b/src/test/ui/nll/issue-46589.stderr
index 397909a436610..82cd364eeffd0 100644
--- a/src/test/ui/nll/issue-46589.stderr
+++ b/src/test/ui/nll/issue-46589.stderr
@@ -1,5 +1,5 @@
 error[E0499]: cannot borrow `**other` as mutable more than once at a time
-  --> $DIR/issue-46589.rs:17:21
+  --> $DIR/issue-46589.rs:23:21
    |
 LL |         *other = match (*other).get_self() {
    |                        -------- first mutable borrow occurs here
diff --git a/src/test/ui/nll/polonius/issue-46589.rs b/src/test/ui/nll/polonius/issue-46589.rs
new file mode 100644
index 0000000000000..b5792587ff0ec
--- /dev/null
+++ b/src/test/ui/nll/polonius/issue-46589.rs
@@ -0,0 +1,32 @@
+// This test is a copy of `ui/nll/issue-46589.rs` which fails in NLL but succeeds in Polonius.
+// As we can't have a test here which conditionally passes depending on a test
+// revision/compile-flags. We ensure here that it passes in Polonius mode.
+
+// check-pass
+// compile-flags: -Z borrowck=mir -Z polonius
+// ignore-compare-mode-nll
+
+struct Foo;
+
+impl Foo {
+    fn get_self(&mut self) -> Option<&mut Self> {
+        Some(self)
+    }
+
+    fn new_self(&mut self) -> &mut Self {
+        self
+    }
+
+    fn trigger_bug(&mut self) {
+        let other = &mut (&mut *self);
+
+        *other = match (*other).get_self() {
+            Some(s) => s,
+            None => (*other).new_self()
+        };
+
+        let c = other;
+    }
+}
+
+fn main() {}

From c0eab36bce7625bc45dec180dd08c7aa679cf1d7 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 16 Jul 2019 17:35:21 +0200
Subject: [PATCH 32/40] Bless output of test nll/loan_ends_mid_block_pair.rs
 for Polonius, again

Fixing assignments to projections made the Polonius output exactly the same as the NLL one.
---
 .../loan_ends_mid_block_pair.polonius.stderr  | 25 +------------------
 1 file changed, 1 insertion(+), 24 deletions(-)

diff --git a/src/test/ui/nll/loan_ends_mid_block_pair.polonius.stderr b/src/test/ui/nll/loan_ends_mid_block_pair.polonius.stderr
index c9537d42c41af..eb8442b31d7c7 100644
--- a/src/test/ui/nll/loan_ends_mid_block_pair.polonius.stderr
+++ b/src/test/ui/nll/loan_ends_mid_block_pair.polonius.stderr
@@ -10,29 +10,6 @@ LL |     data.0 = 'e';
 LL |     capitalize(c);
    |                - borrow later used here
 
-error[E0506]: cannot assign to `data.0` because it is borrowed
-  --> $DIR/loan_ends_mid_block_pair.rs:14:5
-   |
-LL |     let c = &mut data.0;
-   |             ----------- borrow of `data.0` occurs here
-...
-LL |     data.0 = 'f';
-   |     ^^^^^^^^^^^^ assignment to borrowed `data.0` occurs here
-LL |     data.0 = 'g';
-LL |     capitalize(c);
-   |                - borrow later used here
-
-error[E0506]: cannot assign to `data.0` because it is borrowed
-  --> $DIR/loan_ends_mid_block_pair.rs:15:5
-   |
-LL |     let c = &mut data.0;
-   |             ----------- borrow of `data.0` occurs here
-...
-LL |     data.0 = 'g';
-   |     ^^^^^^^^^^^^ assignment to borrowed `data.0` occurs here
-LL |     capitalize(c);
-   |                - borrow later used here
-
-error: aborting due to 3 previous errors
+error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0506`.

From e16bede3f503b85685e80b39942fbc0b0e11a721 Mon Sep 17 00:00:00 2001
From: lqd <remy.rakic+github@gmail.com>
Date: Tue, 16 Jul 2019 18:51:13 +0200
Subject: [PATCH 33/40] fix tidy

---
 src/test/ui/nll/polonius/assignment-kills-loans.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/test/ui/nll/polonius/assignment-kills-loans.rs b/src/test/ui/nll/polonius/assignment-kills-loans.rs
index 8301f603cb4d3..a80c62d19d5a6 100644
--- a/src/test/ui/nll/polonius/assignment-kills-loans.rs
+++ b/src/test/ui/nll/polonius/assignment-kills-loans.rs
@@ -85,4 +85,4 @@ fn assignment_through_projection_chain<T>(
 }
 
 fn main() {
-}
\ No newline at end of file
+}

From 4b339688b5b49e38545336b27845b7d1e31a5b80 Mon Sep 17 00:00:00 2001
From: Brian Cain <bcain@quicinc.com>
Date: Fri, 10 Aug 2018 12:01:18 -0500
Subject: [PATCH 34/40] add support for hexagon-unknown-linux-musl

---
 src/libcore/lib.rs                            |  1 +
 src/libpanic_unwind/gcc.rs                    |  3 +
 src/librustc_codegen_llvm/llvm_util.rs        |  2 +-
 .../spec/hexagon_unknown_linux_musl.rs        | 36 ++++++++++++
 src/librustc_target/spec/mod.rs               |  1 +
 src/libstd/env.rs                             |  5 ++
 src/libstd/os/linux/raw.rs                    | 56 +++++++++++++++++++
 src/libstd/os/raw/mod.rs                      |  2 +
 src/libstd/sys_common/alloc.rs                |  3 +-
 src/libunwind/libunwind.rs                    |  3 +
 10 files changed, 110 insertions(+), 2 deletions(-)
 create mode 100644 src/librustc_target/spec/hexagon_unknown_linux_musl.rs

diff --git a/src/libcore/lib.rs b/src/libcore/lib.rs
index fe149d634e223..2b3bad8894e60 100644
--- a/src/libcore/lib.rs
+++ b/src/libcore/lib.rs
@@ -120,6 +120,7 @@
 #![feature(cmpxchg16b_target_feature)]
 #![feature(rtm_target_feature)]
 #![feature(f16c_target_feature)]
+#![feature(hexagon_target_feature)]
 #![feature(const_slice_len)]
 #![feature(const_str_as_bytes)]
 #![feature(const_str_len)]
diff --git a/src/libpanic_unwind/gcc.rs b/src/libpanic_unwind/gcc.rs
index e2b743b379704..236ed15050571 100644
--- a/src/libpanic_unwind/gcc.rs
+++ b/src/libpanic_unwind/gcc.rs
@@ -126,6 +126,9 @@ const UNWIND_DATA_REG: (i32, i32) = (6, 7); // R6, R7
 #[cfg(target_arch = "sparc64")]
 const UNWIND_DATA_REG: (i32, i32) = (24, 25); // I0, I1
 
+#[cfg(target_arch = "hexagon")]
+const UNWIND_DATA_REG: (i32, i32) = (0, 1); // R0, R1
+
 // The following code is based on GCC's C and C++ personality routines.  For reference, see:
 // https://github.com/gcc-mirror/gcc/blob/master/libstdc++-v3/libsupc++/eh_personality.cc
 // https://github.com/gcc-mirror/gcc/blob/trunk/libgcc/unwind-c.c
diff --git a/src/librustc_codegen_llvm/llvm_util.rs b/src/librustc_codegen_llvm/llvm_util.rs
index 274c89659628d..541d3d98b79bd 100644
--- a/src/librustc_codegen_llvm/llvm_util.rs
+++ b/src/librustc_codegen_llvm/llvm_util.rs
@@ -174,7 +174,7 @@ const X86_WHITELIST: &[(&str, Option<Symbol>)] = &[
 
 const HEXAGON_WHITELIST: &[(&str, Option<Symbol>)] = &[
     ("hvx", Some(sym::hexagon_target_feature)),
-    ("hvx-double", Some(sym::hexagon_target_feature)),
+    ("hvx-length128b", Some(sym::hexagon_target_feature)),
 ];
 
 const POWERPC_WHITELIST: &[(&str, Option<Symbol>)] = &[
diff --git a/src/librustc_target/spec/hexagon_unknown_linux_musl.rs b/src/librustc_target/spec/hexagon_unknown_linux_musl.rs
new file mode 100644
index 0000000000000..1d3b13d488366
--- /dev/null
+++ b/src/librustc_target/spec/hexagon_unknown_linux_musl.rs
@@ -0,0 +1,36 @@
+use crate::spec::{LinkerFlavor, Target, TargetResult, LinkArgs};
+
+pub fn target() -> TargetResult {
+    let mut base = super::linux_musl_base::opts();
+    base.cpu = "hexagonv60".to_string();
+    base.max_atomic_width = Some(32);
+        // FIXME: HVX length defaults are per-CPU
+    base.features = "-small-data,+hvx-length128b".to_string();
+
+    base.crt_static_default = false;
+    base.atomic_cas = true;
+    base.has_rpath = true;
+    base.linker_is_gnu = false;
+    base.dynamic_linking = true;
+    base.executables = true;
+
+    base.pre_link_args = LinkArgs::new();
+    base.post_link_args = LinkArgs::new();
+
+    Ok(Target {
+        llvm_target: "hexagon-unknown-linux-musl".to_string(),
+        target_endian: "little".to_string(),
+        target_pointer_width: "32".to_string(),
+        target_c_int_width: "32".to_string(),
+        data_layout: concat!("e-m:e-p:32:32:32-a:0-n16:32-i64:64:64-i32:32",
+                     ":32-i16:16:16-i1:8:8-f32:32:32-f64:64:64-v32",
+                     ":32:32-v64:64:64-v512:512:512-v1024:1024:1024-v2048",
+                     ":2048:2048").to_string(),
+        arch: "hexagon".to_string(),
+        target_os: "linux".to_string(),
+        target_env: "musl".to_string(),
+        target_vendor: "unknown".to_string(),
+        linker_flavor: LinkerFlavor::Gcc,
+        options: base,
+    })
+}
diff --git a/src/librustc_target/spec/mod.rs b/src/librustc_target/spec/mod.rs
index 1fdc9b015ba39..6a43d97eb925a 100644
--- a/src/librustc_target/spec/mod.rs
+++ b/src/librustc_target/spec/mod.rs
@@ -368,6 +368,7 @@ supported_targets! {
     ("i586-unknown-linux-musl", i586_unknown_linux_musl),
     ("mips-unknown-linux-musl", mips_unknown_linux_musl),
     ("mipsel-unknown-linux-musl", mipsel_unknown_linux_musl),
+    ("hexagon-unknown-linux-musl", hexagon_unknown_linux_musl),
 
     ("mips-unknown-linux-uclibc", mips_unknown_linux_uclibc),
     ("mipsel-unknown-linux-uclibc", mipsel_unknown_linux_uclibc),
diff --git a/src/libstd/env.rs b/src/libstd/env.rs
index 00e840a53e9c0..1f5de25b65c90 100644
--- a/src/libstd/env.rs
+++ b/src/libstd/env.rs
@@ -975,6 +975,11 @@ mod arch {
     pub const ARCH: &str = "wasm32";
 }
 
+#[cfg(target_arch = "hexagon")]
+mod arch {
+    pub const ARCH: &'static str = "hexagon";
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/src/libstd/os/linux/raw.rs b/src/libstd/os/linux/raw.rs
index 77eeacb4b477c..21e1cf8a22b4b 100644
--- a/src/libstd/os/linux/raw.rs
+++ b/src/libstd/os/linux/raw.rs
@@ -147,6 +147,62 @@ mod arch {
     }
 }
 
+#[cfg(target_arch = "hexagon")]
+mod arch {
+    use crate::os::raw::{c_long, c_int, c_longlong, culonglong};
+
+    #[stable(feature = "raw_ext", since = "1.1.0")] pub type blkcnt_t = c_longlong;
+    #[stable(feature = "raw_ext", since = "1.1.0")] pub type blksize_t = c_long;
+    #[stable(feature = "raw_ext", since = "1.1.0")] pub type ino_t = c_ulonglong;
+    #[stable(feature = "raw_ext", since = "1.1.0")] pub type nlink_t = c_uint;
+    #[stable(feature = "raw_ext", since = "1.1.0")] pub type off_t = c_longlong;
+    #[stable(feature = "raw_ext", since = "1.1.0")] pub type time_t = c_long;
+
+    #[repr(C)]
+    #[derive(Clone)]
+    #[stable(feature = "raw_ext", since = "1.1.0")]
+    pub struct stat {
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_dev: ::dev_t,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_ino: ::c_ulonglong,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_mode: ::c_uint,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_nlink: ::c_uint,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_uid: ::c_uint,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_gid: ::c_uint,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_rdev: ::c_ulonglong,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub __pad1: ::c_ulong,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_size: ::c_longlong,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_blksize: ::blksize_t,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub __pad2: ::c_int,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_blocks: ::blkcnt_t,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_atime: ::time_t,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_atime_nsec: ::c_long,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_mtime: ::time_t,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_mtime_nsec: ::c_long,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_ctime: ::time_t,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub st_ctime_nsec: ::c_long,
+        #[stable(feature = "raw_ext", since = "1.1.0")]
+        pub __pad3: [::c_int;2],
+    }
+}
+
 #[cfg(any(target_arch = "mips64",
           target_arch = "s390x",
           target_arch = "sparc64"))]
diff --git a/src/libstd/os/raw/mod.rs b/src/libstd/os/raw/mod.rs
index c0b0b6d40d891..cf8be393a4049 100644
--- a/src/libstd/os/raw/mod.rs
+++ b/src/libstd/os/raw/mod.rs
@@ -11,6 +11,7 @@
 #[doc(include = "os/raw/char.md")]
 #[cfg(any(all(target_os = "linux", any(target_arch = "aarch64",
                                        target_arch = "arm",
+                                       target_arch = "hexagon",
                                        target_arch = "powerpc",
                                        target_arch = "powerpc64",
                                        target_arch = "s390x")),
@@ -34,6 +35,7 @@
 #[doc(include = "os/raw/char.md")]
 #[cfg(not(any(all(target_os = "linux", any(target_arch = "aarch64",
                                            target_arch = "arm",
+                                           target_arch = "hexagon",
                                            target_arch = "powerpc",
                                            target_arch = "powerpc64",
                                            target_arch = "s390x")),
diff --git a/src/libstd/sys_common/alloc.rs b/src/libstd/sys_common/alloc.rs
index 978a70bee0983..1cfc7ed17f2e4 100644
--- a/src/libstd/sys_common/alloc.rs
+++ b/src/libstd/sys_common/alloc.rs
@@ -12,7 +12,8 @@ use crate::ptr;
               target_arch = "powerpc",
               target_arch = "powerpc64",
               target_arch = "asmjs",
-              target_arch = "wasm32")))]
+              target_arch = "wasm32",
+              target_arch = "hexagon")))]
 pub const MIN_ALIGN: usize = 8;
 #[cfg(all(any(target_arch = "x86_64",
               target_arch = "aarch64",
diff --git a/src/libunwind/libunwind.rs b/src/libunwind/libunwind.rs
index 30897970fa220..aacbfc547d472 100644
--- a/src/libunwind/libunwind.rs
+++ b/src/libunwind/libunwind.rs
@@ -56,6 +56,9 @@ pub const unwinder_private_data_size: usize = 2;
 #[cfg(target_os = "emscripten")]
 pub const unwinder_private_data_size: usize = 20;
 
+#[cfg(all(target_arch = "hexagon", target_os = "linux"))]
+pub const unwinder_private_data_size: usize = 35;
+
 #[repr(C)]
 pub struct _Unwind_Exception {
     pub exception_class: _Unwind_Exception_Class,

From 614037171bf0140390033cc60f5e99aac079a0e5 Mon Sep 17 00:00:00 2001
From: Vadim Petrochenkov <vadim.petrochenkov@gmail.com>
Date: Tue, 23 Jul 2019 18:50:47 +0300
Subject: [PATCH 35/40] cleanup: Remove `extern crate serialize as
 rustc_serialize`s

---
 src/librustc/Cargo.toml                     |  2 +-
 src/librustc/hir/def_id.rs                  | 17 ++++++------
 src/librustc/hir/mod.rs                     |  6 ++---
 src/librustc/hir/ptr.rs                     |  2 +-
 src/librustc/infer/canonical/mod.rs         |  2 +-
 src/librustc/lib.rs                         |  8 ------
 src/librustc/lint/context.rs                |  2 +-
 src/librustc/mir/cache.rs                   | 18 ++++++-------
 src/librustc/mir/interpret/allocation.rs    |  2 +-
 src/librustc/mir/interpret/mod.rs           |  6 ++---
 src/librustc/mir/mod.rs                     |  6 ++---
 src/librustc/ty/codec.rs                    |  4 +--
 src/librustc/ty/mod.rs                      | 16 +++++------
 src/librustc/ty/query/on_disk_cache.rs      |  2 +-
 src/librustc/ty/sty.rs                      |  7 +++--
 src/librustc/ty/subst.rs                    |  4 +--
 src/librustc_codegen_ssa/Cargo.toml         |  2 +-
 src/librustc_codegen_ssa/back/linker.rs     |  2 +-
 src/librustc_codegen_ssa/back/wasm.rs       |  2 +-
 src/librustc_data_structures/Cargo.toml     |  2 +-
 src/librustc_data_structures/fingerprint.rs | 11 ++++----
 src/librustc_data_structures/indexed_vec.rs | 30 ++++++++-------------
 src/librustc_data_structures/lib.rs         |  2 --
 src/librustc_data_structures/svh.rs         |  2 +-
 src/librustc_driver/Cargo.toml              |  2 +-
 src/librustc_driver/lib.rs                  |  2 +-
 src/librustc_errors/Cargo.toml              |  2 +-
 src/librustc_errors/lib.rs                  |  3 ---
 src/librustc_incremental/Cargo.toml         |  2 +-
 src/librustc_incremental/lib.rs             |  3 ---
 src/librustc_interface/Cargo.toml           |  2 +-
 src/librustc_interface/passes.rs            |  2 +-
 src/librustc_interface/queries.rs           |  2 +-
 src/librustc_metadata/Cargo.toml            |  2 +-
 src/librustc_metadata/lib.rs                |  2 --
 src/librustc_metadata/schema.rs             |  9 +++----
 src/librustc_mir/Cargo.toml                 |  2 +-
 src/librustc_mir/lib.rs                     |  8 ++----
 src/librustc_target/Cargo.toml              |  2 +-
 src/librustc_target/lib.rs                  |  3 ---
 src/librustc_target/spec/mod.rs             |  6 ++---
 src/libserialize/tests/json.rs              |  1 -
 src/libserialize/tests/opaque.rs            |  1 -
 src/libsyntax/Cargo.toml                    |  2 +-
 src/libsyntax/ast.rs                        |  9 +++----
 src/libsyntax/lib.rs                        |  3 ---
 src/libsyntax/ptr.rs                        |  2 +-
 src/libsyntax/tokenstream.rs                |  2 +-
 src/libsyntax_pos/Cargo.toml                |  2 +-
 src/libsyntax_pos/hygiene.rs                |  2 +-
 src/libsyntax_pos/lib.rs                    |  9 +++----
 src/libsyntax_pos/symbol.rs                 |  2 +-
 52 files changed, 99 insertions(+), 147 deletions(-)

diff --git a/src/librustc/Cargo.toml b/src/librustc/Cargo.toml
index 1677ef4b6079f..0222a3dde7ab9 100644
--- a/src/librustc/Cargo.toml
+++ b/src/librustc/Cargo.toml
@@ -27,7 +27,7 @@ rustc_target = { path = "../librustc_target" }
 rustc_macros = { path = "../librustc_macros" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 errors = { path = "../librustc_errors", package = "rustc_errors" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }
 backtrace = "0.3.3"
diff --git a/src/librustc/hir/def_id.rs b/src/librustc/hir/def_id.rs
index 057d878a0ab8d..f3edb5f862117 100644
--- a/src/librustc/hir/def_id.rs
+++ b/src/librustc/hir/def_id.rs
@@ -1,7 +1,6 @@
 use crate::ty::{self, TyCtxt};
 use crate::hir::map::definitions::FIRST_FREE_DEF_INDEX;
 use rustc_data_structures::indexed_vec::Idx;
-use serialize;
 use std::fmt;
 use std::u32;
 
@@ -93,8 +92,8 @@ impl fmt::Display for CrateNum {
     }
 }
 
-impl serialize::UseSpecializedEncodable for CrateNum {}
-impl serialize::UseSpecializedDecodable for CrateNum {}
+impl rustc_serialize::UseSpecializedEncodable for CrateNum {}
+impl rustc_serialize::UseSpecializedDecodable for CrateNum {}
 
 newtype_index! {
     /// A DefIndex is an index into the hir-map for a crate, identifying a
@@ -134,8 +133,8 @@ impl DefIndex {
     }
 }
 
-impl serialize::UseSpecializedEncodable for DefIndex {}
-impl serialize::UseSpecializedDecodable for DefIndex {}
+impl rustc_serialize::UseSpecializedEncodable for DefIndex {}
+impl rustc_serialize::UseSpecializedDecodable for DefIndex {}
 
 /// A `DefId` identifies a particular *definition*, by combining a crate
 /// index and a def index.
@@ -186,8 +185,8 @@ impl DefId {
     }
 }
 
-impl serialize::UseSpecializedEncodable for DefId {}
-impl serialize::UseSpecializedDecodable for DefId {}
+impl rustc_serialize::UseSpecializedEncodable for DefId {}
+impl rustc_serialize::UseSpecializedDecodable for DefId {}
 
 /// A LocalDefId is equivalent to a DefId with `krate == LOCAL_CRATE`. Since
 /// we encode this information in the type, we can ensure at compile time that
@@ -220,5 +219,5 @@ impl fmt::Debug for LocalDefId {
     }
 }
 
-impl serialize::UseSpecializedEncodable for LocalDefId {}
-impl serialize::UseSpecializedDecodable for LocalDefId {}
+impl rustc_serialize::UseSpecializedEncodable for LocalDefId {}
+impl rustc_serialize::UseSpecializedDecodable for LocalDefId {}
diff --git a/src/librustc/hir/mod.rs b/src/librustc/hir/mod.rs
index e7b37d40b4b2f..3708a905a4b03 100644
--- a/src/librustc/hir/mod.rs
+++ b/src/librustc/hir/mod.rs
@@ -34,7 +34,7 @@ use rustc_data_structures::sync::{par_for_each_in, Send, Sync};
 use rustc_data_structures::thin_vec::ThinVec;
 use rustc_macros::HashStable;
 
-use serialize::{self, Encoder, Encodable, Decoder, Decodable};
+use rustc_serialize::{self, Encoder, Encodable, Decoder, Decodable};
 use std::collections::{BTreeSet, BTreeMap};
 use std::fmt;
 use smallvec::SmallVec;
@@ -92,7 +92,7 @@ impl HirId {
     }
 }
 
-impl serialize::UseSpecializedEncodable for HirId {
+impl rustc_serialize::UseSpecializedEncodable for HirId {
     fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
         let HirId {
             owner,
@@ -104,7 +104,7 @@ impl serialize::UseSpecializedEncodable for HirId {
     }
 }
 
-impl serialize::UseSpecializedDecodable for HirId {
+impl rustc_serialize::UseSpecializedDecodable for HirId {
     fn default_decode<D: Decoder>(d: &mut D) -> Result<HirId, D::Error> {
         let owner = DefIndex::decode(d)?;
         let local_id = ItemLocalId::decode(d)?;
diff --git a/src/librustc/hir/ptr.rs b/src/librustc/hir/ptr.rs
index 3a87b36a1b434..1976b4c9e54ff 100644
--- a/src/librustc/hir/ptr.rs
+++ b/src/librustc/hir/ptr.rs
@@ -7,7 +7,7 @@ use std::iter::FromIterator;
 use std::ops::Deref;
 use std::{slice, vec};
 
-use serialize::{Encodable, Decodable, Encoder, Decoder};
+use rustc_serialize::{Encodable, Decodable, Encoder, Decoder};
 
 use rustc_data_structures::stable_hasher::{StableHasher, StableHasherResult,
                                            HashStable};
diff --git a/src/librustc/infer/canonical/mod.rs b/src/librustc/infer/canonical/mod.rs
index b508f91e01ebb..6840611d4be79 100644
--- a/src/librustc/infer/canonical/mod.rs
+++ b/src/librustc/infer/canonical/mod.rs
@@ -27,7 +27,7 @@ use crate::infer::region_constraints::MemberConstraint;
 use crate::mir::interpret::ConstValue;
 use rustc_data_structures::indexed_vec::IndexVec;
 use rustc_macros::HashStable;
-use serialize::UseSpecializedDecodable;
+use rustc_serialize::UseSpecializedDecodable;
 use smallvec::SmallVec;
 use std::ops::Index;
 use syntax::source_map::Span;
diff --git a/src/librustc/lib.rs b/src/librustc/lib.rs
index 63e0107a4d882..c7d4fa3aec654 100644
--- a/src/librustc/lib.rs
+++ b/src/librustc/lib.rs
@@ -75,16 +75,8 @@ extern crate getopts;
 extern crate libc;
 #[macro_use] extern crate rustc_macros;
 #[macro_use] extern crate rustc_data_structures;
-
 #[macro_use] extern crate log;
 #[macro_use] extern crate syntax;
-
-// FIXME: This import is used by deriving `RustcDecodable` and `RustcEncodable`. Removing this
-// results in a bunch of "failed to resolve" errors. Hopefully, the compiler moves to serde or
-// something, and we can get rid of this.
-#[allow(rust_2018_idioms)]
-extern crate serialize as rustc_serialize;
-
 #[macro_use] extern crate smallvec;
 
 // Use the test crate here so we depend on getopts through it. This allow tools to link to both
diff --git a/src/librustc/lint/context.rs b/src/librustc/lint/context.rs
index 2930f7690dd8e..859bc86d3a07d 100644
--- a/src/librustc/lint/context.rs
+++ b/src/librustc/lint/context.rs
@@ -23,7 +23,7 @@ use crate::lint::{LintArray, Level, Lint, LintId, LintPass, LintBuffer};
 use crate::lint::builtin::BuiltinLintDiagnostics;
 use crate::lint::levels::{LintLevelSets, LintLevelsBuilder};
 use crate::middle::privacy::AccessLevels;
-use crate::rustc_serialize::{Decoder, Decodable, Encoder, Encodable};
+use rustc_serialize::{Decoder, Decodable, Encoder, Encodable};
 use crate::session::{config, early_error, Session};
 use crate::ty::{self, print::Printer, subst::Kind, TyCtxt, Ty};
 use crate::ty::layout::{LayoutError, LayoutOf, TyLayout};
diff --git a/src/librustc/mir/cache.rs b/src/librustc/mir/cache.rs
index d2cabb7e10bbf..3d33e249536c7 100644
--- a/src/librustc/mir/cache.rs
+++ b/src/librustc/mir/cache.rs
@@ -1,27 +1,25 @@
 use rustc_data_structures::indexed_vec::IndexVec;
 use rustc_data_structures::sync::{RwLock, MappedReadGuard, ReadGuard};
-use rustc_data_structures::stable_hasher::{HashStable, StableHasher,
-                                           StableHasherResult};
+use rustc_data_structures::stable_hasher::{HashStable, StableHasher, StableHasherResult};
+use rustc_serialize::{Encodable, Encoder, Decodable, Decoder};
 use crate::ich::StableHashingContext;
 use crate::mir::{Body, BasicBlock};
 
-use crate::rustc_serialize as serialize;
-
 #[derive(Clone, Debug)]
 pub struct Cache {
     predecessors: RwLock<Option<IndexVec<BasicBlock, Vec<BasicBlock>>>>
 }
 
 
-impl serialize::Encodable for Cache {
-    fn encode<S: serialize::Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
-        serialize::Encodable::encode(&(), s)
+impl rustc_serialize::Encodable for Cache {
+    fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+        Encodable::encode(&(), s)
     }
 }
 
-impl serialize::Decodable for Cache {
-    fn decode<D: serialize::Decoder>(d: &mut D) -> Result<Self, D::Error> {
-        serialize::Decodable::decode(d).map(|_v: ()| Self::new())
+impl rustc_serialize::Decodable for Cache {
+    fn decode<D: Decoder>(d: &mut D) -> Result<Self, D::Error> {
+        Decodable::decode(d).map(|_v: ()| Self::new())
     }
 }
 
diff --git a/src/librustc/mir/interpret/allocation.rs b/src/librustc/mir/interpret/allocation.rs
index c8bf250d02b36..51b2d0272a597 100644
--- a/src/librustc/mir/interpret/allocation.rs
+++ b/src/librustc/mir/interpret/allocation.rs
@@ -113,7 +113,7 @@ impl<Tag> Allocation<Tag> {
     }
 }
 
-impl<'tcx> ::serialize::UseSpecializedDecodable for &'tcx Allocation {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for &'tcx Allocation {}
 
 /// Byte accessors
 impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> {
diff --git a/src/librustc/mir/interpret/mod.rs b/src/librustc/mir/interpret/mod.rs
index 1b294250aa3dc..3e9933a24750e 100644
--- a/src/librustc/mir/interpret/mod.rs
+++ b/src/librustc/mir/interpret/mod.rs
@@ -27,7 +27,7 @@ use crate::hir::def_id::DefId;
 use crate::ty::{self, TyCtxt, Instance, subst::UnpackedKind};
 use crate::ty::layout::{self, Size};
 use std::io;
-use crate::rustc_serialize::{Encoder, Decodable, Encodable};
+use rustc_serialize::{Encoder, Decodable, Encodable};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::{Lock as Mutex, HashMapExt};
 use rustc_data_structures::tiny_list::TinyList;
@@ -51,8 +51,8 @@ pub struct GlobalId<'tcx> {
 #[derive(Copy, Clone, Eq, Hash, Ord, PartialEq, PartialOrd, Debug)]
 pub struct AllocId(pub u64);
 
-impl crate::rustc_serialize::UseSpecializedEncodable for AllocId {}
-impl crate::rustc_serialize::UseSpecializedDecodable for AllocId {}
+impl rustc_serialize::UseSpecializedEncodable for AllocId {}
+impl rustc_serialize::UseSpecializedDecodable for AllocId {}
 
 #[derive(RustcDecodable, RustcEncodable)]
 enum AllocDiscriminant {
diff --git a/src/librustc/mir/mod.rs b/src/librustc/mir/mod.rs
index d8b641fbe31f4..571fc56a54e54 100644
--- a/src/librustc/mir/mod.rs
+++ b/src/librustc/mir/mod.rs
@@ -9,7 +9,6 @@ use crate::hir::def_id::DefId;
 use crate::hir::{self, InlineAsm as HirInlineAsm};
 use crate::mir::interpret::{ConstValue, InterpError, Scalar};
 use crate::mir::visit::MirVisitable;
-use crate::rustc_serialize as serialize;
 use crate::ty::adjustment::PointerCast;
 use crate::ty::fold::{TypeFoldable, TypeFolder, TypeVisitor};
 use crate::ty::layout::VariantIdx;
@@ -28,6 +27,7 @@ use rustc_data_structures::indexed_vec::{Idx, IndexVec};
 use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::sync::MappedReadGuard;
 use rustc_macros::HashStable;
+use rustc_serialize::{Encodable, Decodable};
 use smallvec::SmallVec;
 use std::borrow::Cow;
 use std::fmt::{self, Debug, Display, Formatter, Write};
@@ -463,8 +463,8 @@ impl<T> ClearCrossCrate<T> {
     }
 }
 
-impl<T: serialize::Encodable> serialize::UseSpecializedEncodable for ClearCrossCrate<T> {}
-impl<T: serialize::Decodable> serialize::UseSpecializedDecodable for ClearCrossCrate<T> {}
+impl<T: Encodable> rustc_serialize::UseSpecializedEncodable for ClearCrossCrate<T> {}
+impl<T: Decodable> rustc_serialize::UseSpecializedDecodable for ClearCrossCrate<T> {}
 
 /// Grouped information about the source code origin of a MIR entity.
 /// Intended to be inspected by diagnostics and debuginfo.
diff --git a/src/librustc/ty/codec.rs b/src/librustc/ty/codec.rs
index 26e7cc9004d4e..e3c6eca02d554 100644
--- a/src/librustc/ty/codec.rs
+++ b/src/librustc/ty/codec.rs
@@ -10,7 +10,7 @@ use crate::arena::ArenaAllocatable;
 use crate::hir::def_id::{DefId, CrateNum};
 use crate::infer::canonical::{CanonicalVarInfo, CanonicalVarInfos};
 use rustc_data_structures::fx::FxHashMap;
-use crate::rustc_serialize::{Decodable, Decoder, Encoder, Encodable, opaque};
+use rustc_serialize::{Decodable, Decoder, Encoder, Encodable, opaque};
 use std::hash::Hash;
 use std::intrinsics;
 use crate::ty::{self, Ty, TyCtxt};
@@ -333,7 +333,7 @@ macro_rules! implement_ty_decoder {
             use $crate::ty::codec::*;
             use $crate::ty::subst::SubstsRef;
             use $crate::hir::def_id::{CrateNum};
-            use crate::rustc_serialize::{Decoder, SpecializedDecoder};
+            use rustc_serialize::{Decoder, SpecializedDecoder};
             use std::borrow::Cow;
 
             impl<$($typaram ),*> Decoder for $DecoderName<$($typaram),*> {
diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index 538afa6054ff9..44897c8e90376 100644
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -32,7 +32,7 @@ use crate::util::nodemap::{NodeSet, DefIdMap, FxHashMap};
 use arena::SyncDroplessArena;
 use crate::session::DataTypeKind;
 
-use serialize::{self, Encodable, Encoder};
+use rustc_serialize::{self, Encodable, Encoder};
 use std::cell::RefCell;
 use std::cmp::{self, Ordering};
 use std::fmt;
@@ -588,8 +588,8 @@ impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for ty::TyS<'tcx> {
 
 pub type Ty<'tcx> = &'tcx TyS<'tcx>;
 
-impl<'tcx> serialize::UseSpecializedEncodable for Ty<'tcx> {}
-impl<'tcx> serialize::UseSpecializedDecodable for Ty<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedEncodable for Ty<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for Ty<'tcx> {}
 
 pub type CanonicalTy<'tcx> = Canonical<'tcx, Ty<'tcx>>;
 
@@ -708,7 +708,7 @@ impl<'a, T> IntoIterator for &'a List<T> {
     }
 }
 
-impl<'tcx> serialize::UseSpecializedDecodable for &'tcx List<Ty<'tcx>> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for &'tcx List<Ty<'tcx>> {}
 
 impl<T> List<T> {
     #[inline(always)]
@@ -1009,8 +1009,8 @@ pub struct GenericPredicates<'tcx> {
     pub predicates: Vec<(Predicate<'tcx>, Span)>,
 }
 
-impl<'tcx> serialize::UseSpecializedEncodable for GenericPredicates<'tcx> {}
-impl<'tcx> serialize::UseSpecializedDecodable for GenericPredicates<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedEncodable for GenericPredicates<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for GenericPredicates<'tcx> {}
 
 impl<'tcx> GenericPredicates<'tcx> {
     pub fn instantiate(
@@ -1985,13 +1985,13 @@ impl Hash for AdtDef {
     }
 }
 
-impl<'tcx> serialize::UseSpecializedEncodable for &'tcx AdtDef {
+impl<'tcx> rustc_serialize::UseSpecializedEncodable for &'tcx AdtDef {
     fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
         self.did.encode(s)
     }
 }
 
-impl<'tcx> serialize::UseSpecializedDecodable for &'tcx AdtDef {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for &'tcx AdtDef {}
 
 
 impl<'a> HashStable<StableHashingContext<'a>> for AdtDef {
diff --git a/src/librustc/ty/query/on_disk_cache.rs b/src/librustc/ty/query/on_disk_cache.rs
index a25c1e34cf154..211a28fe9315f 100644
--- a/src/librustc/ty/query/on_disk_cache.rs
+++ b/src/librustc/ty/query/on_disk_cache.rs
@@ -5,7 +5,7 @@ use crate::hir::map::definitions::DefPathHash;
 use crate::ich::{CachingSourceMapView, Fingerprint};
 use crate::mir::{self, interpret};
 use crate::mir::interpret::{AllocDecodingSession, AllocDecodingState};
-use crate::rustc_serialize::{Decodable, Decoder, Encodable, Encoder, opaque,
+use rustc_serialize::{Decodable, Decoder, Encodable, Encoder, opaque,
                       SpecializedDecoder, SpecializedEncoder,
                       UseSpecializedDecodable, UseSpecializedEncodable};
 use crate::session::{CrateDisambiguator, Session};
diff --git a/src/librustc/ty/sty.rs b/src/librustc/ty/sty.rs
index 5d17080a9b2bc..49a0fd827fbd8 100644
--- a/src/librustc/ty/sty.rs
+++ b/src/librustc/ty/sty.rs
@@ -26,7 +26,6 @@ use rustc_target::spec::abi;
 use syntax::ast::{self, Ident};
 use syntax::symbol::{kw, InternedString};
 
-use serialize;
 use self::InferTy::*;
 use self::TyKind::*;
 
@@ -640,7 +639,7 @@ impl<'tcx> Binder<ExistentialPredicate<'tcx>> {
     }
 }
 
-impl<'tcx> serialize::UseSpecializedDecodable for &'tcx List<ExistentialPredicate<'tcx>> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for &'tcx List<ExistentialPredicate<'tcx>> {}
 
 impl<'tcx> List<ExistentialPredicate<'tcx>> {
     /// Returns the "principal def id" of this set of existential predicates.
@@ -1324,7 +1323,7 @@ pub enum RegionKind {
     ReClosureBound(RegionVid),
 }
 
-impl<'tcx> serialize::UseSpecializedDecodable for Region<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for Region<'tcx> {}
 
 #[derive(Copy, Clone, PartialEq, Eq, Hash, RustcEncodable, RustcDecodable, Debug, PartialOrd, Ord)]
 pub struct EarlyBoundRegion {
@@ -2333,7 +2332,7 @@ impl<'tcx> Const<'tcx> {
     }
 }
 
-impl<'tcx> serialize::UseSpecializedDecodable for &'tcx Const<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for &'tcx Const<'tcx> {}
 
 /// An inference variable for a const, for use in const generics.
 #[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd,
diff --git a/src/librustc/ty/subst.rs b/src/librustc/ty/subst.rs
index 79dcd327f52d4..ea829da783e9b 100644
--- a/src/librustc/ty/subst.rs
+++ b/src/librustc/ty/subst.rs
@@ -6,7 +6,7 @@ use crate::ty::{self, Lift, List, Ty, TyCtxt, InferConst, ParamConst};
 use crate::ty::fold::{TypeFoldable, TypeFolder, TypeVisitor};
 use crate::mir::interpret::ConstValue;
 
-use serialize::{self, Encodable, Encoder, Decodable, Decoder};
+use rustc_serialize::{self, Encodable, Encoder, Decodable, Decoder};
 use syntax_pos::{Span, DUMMY_SP};
 use smallvec::SmallVec;
 use rustc_macros::HashStable;
@@ -399,7 +399,7 @@ impl<'tcx> TypeFoldable<'tcx> for SubstsRef<'tcx> {
     }
 }
 
-impl<'tcx> serialize::UseSpecializedDecodable for SubstsRef<'tcx> {}
+impl<'tcx> rustc_serialize::UseSpecializedDecodable for SubstsRef<'tcx> {}
 
 ///////////////////////////////////////////////////////////////////////////
 // Public trait `Subst`
diff --git a/src/librustc_codegen_ssa/Cargo.toml b/src/librustc_codegen_ssa/Cargo.toml
index e7ee06df7e12d..90d7320987c95 100644
--- a/src/librustc_codegen_ssa/Cargo.toml
+++ b/src/librustc_codegen_ssa/Cargo.toml
@@ -20,7 +20,7 @@ jobserver = "0.1.11"
 parking_lot = "0.7"
 tempfile = "3.0.5"
 
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }
 rustc = { path = "../librustc" }
diff --git a/src/librustc_codegen_ssa/back/linker.rs b/src/librustc_codegen_ssa/back/linker.rs
index 32696d46cd577..882963f9174ec 100644
--- a/src/librustc_codegen_ssa/back/linker.rs
+++ b/src/librustc_codegen_ssa/back/linker.rs
@@ -16,7 +16,7 @@ use rustc::session::config::{self, CrateType, OptLevel, DebugInfo,
                              LinkerPluginLto, Lto};
 use rustc::ty::TyCtxt;
 use rustc_target::spec::{LinkerFlavor, LldFlavor};
-use serialize::{json, Encoder};
+use rustc_serialize::{json, Encoder};
 
 /// For all the linkers we support, and information they might
 /// need out of the shared crate context before we get rid of it.
diff --git a/src/librustc_codegen_ssa/back/wasm.rs b/src/librustc_codegen_ssa/back/wasm.rs
index f90bb89fbe87d..2a9e81a788e52 100644
--- a/src/librustc_codegen_ssa/back/wasm.rs
+++ b/src/librustc_codegen_ssa/back/wasm.rs
@@ -2,7 +2,7 @@ use std::fs;
 use std::path::Path;
 use std::str;
 
-use serialize::leb128;
+use rustc_serialize::leb128;
 
 // https://webassembly.github.io/spec/core/binary/modules.html#binary-importsec
 const WASM_CUSTOM_SECTION_ID: u8 = 0;
diff --git a/src/librustc_data_structures/Cargo.toml b/src/librustc_data_structures/Cargo.toml
index 79cbe26e73e83..288676ce3ff67 100644
--- a/src/librustc_data_structures/Cargo.toml
+++ b/src/librustc_data_structures/Cargo.toml
@@ -15,7 +15,7 @@ indexmap = "1"
 log = "0.4"
 jobserver_crate = { version = "0.1.13", package = "jobserver" }
 lazy_static = "1"
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 graphviz = { path = "../libgraphviz" }
 cfg-if = "0.1.2"
 crossbeam-utils = { version = "0.6.5", features = ["nightly"] }
diff --git a/src/librustc_data_structures/fingerprint.rs b/src/librustc_data_structures/fingerprint.rs
index 3bea965ef3041..c8012bb942461 100644
--- a/src/librustc_data_structures/fingerprint.rs
+++ b/src/librustc_data_structures/fingerprint.rs
@@ -1,7 +1,6 @@
 use crate::stable_hasher;
 use std::mem;
-use serialize;
-use serialize::opaque::{EncodeResult, Encoder, Decoder};
+use rustc_serialize::opaque::{EncodeResult, Encoder, Decoder};
 
 #[derive(Eq, PartialEq, Ord, PartialOrd, Hash, Debug, Clone, Copy)]
 pub struct Fingerprint(u64, u64);
@@ -85,17 +84,17 @@ impl stable_hasher::StableHasherResult for Fingerprint {
 
 impl_stable_hash_via_hash!(Fingerprint);
 
-impl serialize::UseSpecializedEncodable for Fingerprint { }
+impl rustc_serialize::UseSpecializedEncodable for Fingerprint { }
 
-impl serialize::UseSpecializedDecodable for Fingerprint { }
+impl rustc_serialize::UseSpecializedDecodable for Fingerprint { }
 
-impl serialize::SpecializedEncoder<Fingerprint> for serialize::opaque::Encoder {
+impl rustc_serialize::SpecializedEncoder<Fingerprint> for Encoder {
     fn specialized_encode(&mut self, f: &Fingerprint) -> Result<(), Self::Error> {
         f.encode_opaque(self)
     }
 }
 
-impl<'a> serialize::SpecializedDecoder<Fingerprint> for serialize::opaque::Decoder<'a> {
+impl<'a> rustc_serialize::SpecializedDecoder<Fingerprint> for Decoder<'a> {
     fn specialized_decode(&mut self) -> Result<Fingerprint, Self::Error> {
         Fingerprint::decode_opaque(self)
     }
diff --git a/src/librustc_data_structures/indexed_vec.rs b/src/librustc_data_structures/indexed_vec.rs
index c3c76e8160615..6f40d059be27f 100644
--- a/src/librustc_data_structures/indexed_vec.rs
+++ b/src/librustc_data_structures/indexed_vec.rs
@@ -1,3 +1,5 @@
+use rustc_serialize::{Encodable, Decodable, Encoder, Decoder};
+
 use std::fmt::Debug;
 use std::iter::{self, FromIterator};
 use std::slice;
@@ -8,8 +10,6 @@ use std::hash::Hash;
 use std::vec;
 use std::u32;
 
-use rustc_serialize as serialize;
-
 /// Represents some newtyped `usize` wrapper.
 ///
 /// Purpose: avoid mixing indexes for different bitvector domains.
@@ -398,17 +398,9 @@ macro_rules! newtype_index {
     );
 
     (@decodable $type:ident) => (
-        impl $type {
-            fn __decodable__impl__hack() {
-                mod __more_hacks_because__self_doesnt_work_in_functions {
-                    extern crate serialize;
-                    use self::serialize::{Decodable, Decoder};
-                    impl Decodable for super::$type {
-                        fn decode<D: Decoder>(d: &mut D) -> Result<Self, D::Error> {
-                            d.read_u32().map(Self::from)
-                        }
-                    }
-                }
+        impl ::rustc_serialize::Decodable for $type {
+            fn decode<D: ::rustc_serialize::Decoder>(d: &mut D) -> Result<Self, D::Error> {
+                d.read_u32().map(Self::from)
             }
         }
     );
@@ -521,15 +513,15 @@ pub struct IndexVec<I: Idx, T> {
 // not the phantom data.
 unsafe impl<I: Idx, T> Send for IndexVec<I, T> where T: Send {}
 
-impl<I: Idx, T: serialize::Encodable> serialize::Encodable for IndexVec<I, T> {
-    fn encode<S: serialize::Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
-        serialize::Encodable::encode(&self.raw, s)
+impl<I: Idx, T: Encodable> Encodable for IndexVec<I, T> {
+    fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+        Encodable::encode(&self.raw, s)
     }
 }
 
-impl<I: Idx, T: serialize::Decodable> serialize::Decodable for IndexVec<I, T> {
-    fn decode<D: serialize::Decoder>(d: &mut D) -> Result<Self, D::Error> {
-        serialize::Decodable::decode(d).map(|v| {
+impl<I: Idx, T: Decodable> Decodable for IndexVec<I, T> {
+    fn decode<D: Decoder>(d: &mut D) -> Result<Self, D::Error> {
+        Decodable::decode(d).map(|v| {
             IndexVec { raw: v, _marker: PhantomData }
         })
     }
diff --git a/src/librustc_data_structures/lib.rs b/src/librustc_data_structures/lib.rs
index a2407681e6d3f..3047119029abc 100644
--- a/src/librustc_data_structures/lib.rs
+++ b/src/librustc_data_structures/lib.rs
@@ -31,8 +31,6 @@
 
 #[macro_use]
 extern crate log;
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
 #[cfg(unix)]
 extern crate libc;
 #[macro_use]
diff --git a/src/librustc_data_structures/svh.rs b/src/librustc_data_structures/svh.rs
index df4f61768375e..3123c182b0f4c 100644
--- a/src/librustc_data_structures/svh.rs
+++ b/src/librustc_data_structures/svh.rs
@@ -7,7 +7,7 @@
 
 use std::fmt;
 use std::hash::{Hash, Hasher};
-use serialize::{Encodable, Decodable, Encoder, Decoder};
+use rustc_serialize::{Encodable, Decodable, Encoder, Decoder};
 
 use crate::stable_hasher;
 
diff --git a/src/librustc_driver/Cargo.toml b/src/librustc_driver/Cargo.toml
index d4c30dc6c4507..3162af5086d80 100644
--- a/src/librustc_driver/Cargo.toml
+++ b/src/librustc_driver/Cargo.toml
@@ -34,7 +34,7 @@ rustc_traits = { path = "../librustc_traits" }
 rustc_codegen_utils = { path = "../librustc_codegen_utils" }
 rustc_typeck = { path = "../librustc_typeck" }
 rustc_interface = { path = "../librustc_interface" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax = { path = "../libsyntax" }
 smallvec = { version = "0.6.7", features = ["union", "may_dangle"] }
 syntax_ext = { path = "../libsyntax_ext" }
diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs
index 2bc79e5080f3a..c139be07aa1d3 100644
--- a/src/librustc_driver/lib.rs
+++ b/src/librustc_driver/lib.rs
@@ -46,7 +46,7 @@ use rustc_interface::interface;
 use rustc_interface::util::get_codegen_sysroot;
 use rustc_data_structures::sync::SeqCst;
 
-use serialize::json::ToJson;
+use rustc_serialize::json::ToJson;
 
 use std::borrow::Cow;
 use std::cmp::max;
diff --git a/src/librustc_errors/Cargo.toml b/src/librustc_errors/Cargo.toml
index 4df9632cce26b..5a192e472aa85 100644
--- a/src/librustc_errors/Cargo.toml
+++ b/src/librustc_errors/Cargo.toml
@@ -11,7 +11,7 @@ doctest = false
 
 [dependencies]
 log = "0.4"
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax_pos = { path = "../libsyntax_pos" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 unicode-width = "0.1.4"
diff --git a/src/librustc_errors/lib.rs b/src/librustc_errors/lib.rs
index 3269b85d0dd13..0a6c02c0ca68f 100644
--- a/src/librustc_errors/lib.rs
+++ b/src/librustc_errors/lib.rs
@@ -12,9 +12,6 @@
 #![deny(rust_2018_idioms)]
 #![deny(unused_lifetimes)]
 
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
-
 pub use emitter::ColorConfig;
 
 use Level::*;
diff --git a/src/librustc_incremental/Cargo.toml b/src/librustc_incremental/Cargo.toml
index 9678cb4f65545..a931ad3b66e21 100644
--- a/src/librustc_incremental/Cargo.toml
+++ b/src/librustc_incremental/Cargo.toml
@@ -15,7 +15,7 @@ log = "0.4"
 rand = "0.6"
 rustc = { path = "../librustc" }
 rustc_data_structures = { path = "../librustc_data_structures" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }
 rustc_fs_util = { path = "../librustc_fs_util" }
diff --git a/src/librustc_incremental/lib.rs b/src/librustc_incremental/lib.rs
index 569aa78c9d4b3..55aba7caa9d42 100644
--- a/src/librustc_incremental/lib.rs
+++ b/src/librustc_incremental/lib.rs
@@ -12,9 +12,6 @@
 #![deny(unused_lifetimes)]
 
 #[macro_use] extern crate rustc;
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
-
 #[macro_use] extern crate log;
 
 mod assert_dep_graph;
diff --git a/src/librustc_interface/Cargo.toml b/src/librustc_interface/Cargo.toml
index a0efec5ee7a7f..a90254e7e185f 100644
--- a/src/librustc_interface/Cargo.toml
+++ b/src/librustc_interface/Cargo.toml
@@ -16,7 +16,7 @@ smallvec = { version = "0.6.7", features = ["union", "may_dangle"] }
 syntax = { path = "../libsyntax" }
 syntax_ext = { path = "../libsyntax_ext" }
 syntax_pos = { path = "../libsyntax_pos" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 rustc = { path = "../librustc" }
 rustc_allocator = { path = "../librustc_allocator" }
 rustc_ast_borrowck = { path = "../librustc_ast_borrowck" }
diff --git a/src/librustc_interface/passes.rs b/src/librustc_interface/passes.rs
index 6bf56bf851553..5298f99d54803 100644
--- a/src/librustc_interface/passes.rs
+++ b/src/librustc_interface/passes.rs
@@ -51,7 +51,7 @@ use syntax::feature_gate::AttributeType;
 use syntax_pos::{FileName, edition::Edition, hygiene};
 use syntax_ext;
 
-use serialize::json;
+use rustc_serialize::json;
 use tempfile::Builder as TempFileBuilder;
 
 use std::any::Any;
diff --git a/src/librustc_interface/queries.rs b/src/librustc_interface/queries.rs
index 570509ffb2b8c..9b79dc6350ca6 100644
--- a/src/librustc_interface/queries.rs
+++ b/src/librustc_interface/queries.rs
@@ -15,7 +15,7 @@ use rustc::ty::steal::Steal;
 use rustc::dep_graph::DepGraph;
 use rustc_passes::hir_stats;
 use rustc_plugin::registry::Registry;
-use serialize::json;
+use rustc_serialize::json;
 use std::cell::{Ref, RefMut, RefCell};
 use std::ops::Deref;
 use std::rc::Rc;
diff --git a/src/librustc_metadata/Cargo.toml b/src/librustc_metadata/Cargo.toml
index e5c9f1bf2057b..a9f054d5e8be8 100644
--- a/src/librustc_metadata/Cargo.toml
+++ b/src/librustc_metadata/Cargo.toml
@@ -18,7 +18,7 @@ rustc = { path = "../librustc" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 errors = { path = "../librustc_errors", package = "rustc_errors" }
 rustc_target = { path = "../librustc_target" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 stable_deref_trait = "1.0.0"
 syntax = { path = "../libsyntax" }
 syntax_ext = { path = "../libsyntax_ext" }
diff --git a/src/librustc_metadata/lib.rs b/src/librustc_metadata/lib.rs
index 826349362db25..b0fe06039f4e2 100644
--- a/src/librustc_metadata/lib.rs
+++ b/src/librustc_metadata/lib.rs
@@ -18,8 +18,6 @@
 #![deny(unused_lifetimes)]
 
 extern crate libc;
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
 extern crate proc_macro;
 
 #[macro_use]
diff --git a/src/librustc_metadata/schema.rs b/src/librustc_metadata/schema.rs
index 8d1de4fd6c392..b7dd1d03e44ae 100644
--- a/src/librustc_metadata/schema.rs
+++ b/src/librustc_metadata/schema.rs
@@ -13,7 +13,6 @@ use rustc::ty::{self, Ty, ReprOptions};
 use rustc_target::spec::{PanicStrategy, TargetTriple};
 use rustc_data_structures::svh::Svh;
 
-use rustc_serialize as serialize;
 use syntax::{ast, attr};
 use syntax::edition::Edition;
 use syntax::symbol::Symbol;
@@ -85,8 +84,8 @@ impl<T> Clone for Lazy<T> {
     }
 }
 
-impl<T> serialize::UseSpecializedEncodable for Lazy<T> {}
-impl<T> serialize::UseSpecializedDecodable for Lazy<T> {}
+impl<T> rustc_serialize::UseSpecializedEncodable for Lazy<T> {}
+impl<T> rustc_serialize::UseSpecializedDecodable for Lazy<T> {}
 
 /// A sequence of type T referred to by its absolute position
 /// in the metadata and length, and which can be decoded lazily.
@@ -133,8 +132,8 @@ impl<T> Clone for LazySeq<T> {
     }
 }
 
-impl<T> serialize::UseSpecializedEncodable for LazySeq<T> {}
-impl<T> serialize::UseSpecializedDecodable for LazySeq<T> {}
+impl<T> rustc_serialize::UseSpecializedEncodable for LazySeq<T> {}
+impl<T> rustc_serialize::UseSpecializedDecodable for LazySeq<T> {}
 
 /// Encoding / decoding state for `Lazy` and `LazySeq`.
 #[derive(Copy, Clone, PartialEq, Eq, Debug)]
diff --git a/src/librustc_mir/Cargo.toml b/src/librustc_mir/Cargo.toml
index 2adbd03b24ff1..21008c737289f 100644
--- a/src/librustc_mir/Cargo.toml
+++ b/src/librustc_mir/Cargo.toml
@@ -20,7 +20,7 @@ rustc = { path = "../librustc" }
 rustc_target = { path = "../librustc_target" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 rustc_errors = { path = "../librustc_errors" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }
 byteorder = { version = "1.1", features = ["i128"] }
diff --git a/src/librustc_mir/lib.rs b/src/librustc_mir/lib.rs
index f5e4661afa6b1..964f04d79b960 100644
--- a/src/librustc_mir/lib.rs
+++ b/src/librustc_mir/lib.rs
@@ -30,13 +30,9 @@ Rust MIR: a lowered representation of Rust. Also: an experiment!
 #![deny(unused_lifetimes)]
 
 #[macro_use] extern crate log;
-#[macro_use]
-extern crate rustc;
+#[macro_use] extern crate rustc;
 #[macro_use] extern crate rustc_data_structures;
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
-#[macro_use]
-extern crate syntax;
+#[macro_use] extern crate syntax;
 
 mod error_codes;
 
diff --git a/src/librustc_target/Cargo.toml b/src/librustc_target/Cargo.toml
index f1b21365e4bd4..cab1e0e01371d 100644
--- a/src/librustc_target/Cargo.toml
+++ b/src/librustc_target/Cargo.toml
@@ -12,5 +12,5 @@ path = "lib.rs"
 bitflags = "1.0"
 log = "0.4"
 rustc_data_structures = { path = "../librustc_data_structures" }
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax_pos = { path = "../libsyntax_pos" }
diff --git a/src/librustc_target/lib.rs b/src/librustc_target/lib.rs
index dcd1eb5acdc85..a14bc66cc3833 100644
--- a/src/librustc_target/lib.rs
+++ b/src/librustc_target/lib.rs
@@ -18,8 +18,5 @@
 
 #[macro_use] extern crate log;
 
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
-
 pub mod abi;
 pub mod spec;
diff --git a/src/librustc_target/spec/mod.rs b/src/librustc_target/spec/mod.rs
index 1fdc9b015ba39..cda0dbef843b8 100644
--- a/src/librustc_target/spec/mod.rs
+++ b/src/librustc_target/spec/mod.rs
@@ -34,7 +34,7 @@
 //! the target's settings, though `target-feature` and `link-args` will *add*
 //! to the list specified by the target, rather than replace.
 
-use serialize::json::{Json, ToJson};
+use rustc_serialize::json::{Json, ToJson};
 use std::collections::BTreeMap;
 use std::default::Default;
 use std::{fmt, io};
@@ -306,7 +306,7 @@ macro_rules! supported_targets {
 
         #[cfg(test)]
         mod test_json_encode_decode {
-            use serialize::json::ToJson;
+            use rustc_serialize::json::ToJson;
             use super::Target;
             $(use super::$module;)+
 
@@ -1198,7 +1198,7 @@ impl Target {
     pub fn search(target_triple: &TargetTriple) -> Result<Target, String> {
         use std::env;
         use std::fs;
-        use serialize::json;
+        use rustc_serialize::json;
 
         fn load_file(path: &Path) -> Result<Target, String> {
             let contents = fs::read(path).map_err(|e| e.to_string())?;
diff --git a/src/libserialize/tests/json.rs b/src/libserialize/tests/json.rs
index 0fe3d4cfd6297..3fb6bda679bc1 100644
--- a/src/libserialize/tests/json.rs
+++ b/src/libserialize/tests/json.rs
@@ -1,4 +1,3 @@
-#[allow(unused_extern_crates)]
 extern crate serialize as rustc_serialize;
 
 use rustc_serialize::{Encodable, Decodable};
diff --git a/src/libserialize/tests/opaque.rs b/src/libserialize/tests/opaque.rs
index 62a8f25124439..fff6fc69e7842 100644
--- a/src/libserialize/tests/opaque.rs
+++ b/src/libserialize/tests/opaque.rs
@@ -1,4 +1,3 @@
-#[allow(unused_extern_crates)]
 extern crate serialize as rustc_serialize;
 
 use rustc_serialize::{Encodable, Decodable};
diff --git a/src/libsyntax/Cargo.toml b/src/libsyntax/Cargo.toml
index 15c685b3b7b50..d4a9acc1569b4 100644
--- a/src/libsyntax/Cargo.toml
+++ b/src/libsyntax/Cargo.toml
@@ -11,7 +11,7 @@ doctest = false
 
 [dependencies]
 bitflags = "1.0"
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 log = "0.4"
 scoped-tls = "1.0"
 lazy_static = "1.0.0"
diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index b9b43c89346c7..dbfad3ef7f4de 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -22,7 +22,7 @@ use syntax_pos::{Span, DUMMY_SP};
 
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::sync::Lrc;
-use serialize::{self, Decoder, Encoder};
+use rustc_serialize::{self, Decoder, Encoder};
 use std::fmt;
 
 pub use rustc_target::abi::FloatTy;
@@ -266,13 +266,13 @@ impl fmt::Display for NodeId {
     }
 }
 
-impl serialize::UseSpecializedEncodable for NodeId {
+impl rustc_serialize::UseSpecializedEncodable for NodeId {
     fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
         s.emit_u32(self.as_u32())
     }
 }
 
-impl serialize::UseSpecializedDecodable for NodeId {
+impl rustc_serialize::UseSpecializedDecodable for NodeId {
     fn default_decode<D: Decoder>(d: &mut D) -> Result<NodeId, D::Error> {
         d.read_u32().map(NodeId::from_u32)
     }
@@ -2414,12 +2414,11 @@ impl ForeignItemKind {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use serialize;
 
     // Are ASTs encodable?
     #[test]
     fn check_asts_encodable() {
-        fn assert_encodable<T: serialize::Encodable>() {}
+        fn assert_encodable<T: rustc_serialize::Encodable>() {}
         assert_encodable::<Crate>();
     }
 }
diff --git a/src/libsyntax/lib.rs b/src/libsyntax/lib.rs
index 3dea1977c4dac..0507a322a5fb2 100644
--- a/src/libsyntax/lib.rs
+++ b/src/libsyntax/lib.rs
@@ -24,9 +24,6 @@
 
 #![recursion_limit="256"]
 
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
-
 pub use errors;
 use rustc_data_structures::sync::Lock;
 use rustc_data_structures::bit_set::GrowableBitSet;
diff --git a/src/libsyntax/ptr.rs b/src/libsyntax/ptr.rs
index be580dc2e6a7e..b5eb8ca94c07a 100644
--- a/src/libsyntax/ptr.rs
+++ b/src/libsyntax/ptr.rs
@@ -31,7 +31,7 @@ use std::iter::FromIterator;
 use std::ops::{Deref, DerefMut};
 use std::{slice, vec};
 
-use serialize::{Encodable, Decodable, Encoder, Decoder};
+use rustc_serialize::{Encodable, Decodable, Encoder, Decoder};
 
 use rustc_data_structures::stable_hasher::{StableHasher, StableHasherResult,
                                            HashStable};
diff --git a/src/libsyntax/tokenstream.rs b/src/libsyntax/tokenstream.rs
index 88142344d79e0..34e68944926df 100644
--- a/src/libsyntax/tokenstream.rs
+++ b/src/libsyntax/tokenstream.rs
@@ -23,7 +23,7 @@ use syntax_pos::{BytePos, ExpnId, Span, DUMMY_SP};
 #[cfg(target_arch = "x86_64")]
 use rustc_data_structures::static_assert_size;
 use rustc_data_structures::sync::Lrc;
-use serialize::{Decoder, Decodable, Encoder, Encodable};
+use rustc_serialize::{Decoder, Decodable, Encoder, Encodable};
 use smallvec::{SmallVec, smallvec};
 
 use std::borrow::Cow;
diff --git a/src/libsyntax_pos/Cargo.toml b/src/libsyntax_pos/Cargo.toml
index eebd25d1fafd8..bc13d2a161132 100644
--- a/src/libsyntax_pos/Cargo.toml
+++ b/src/libsyntax_pos/Cargo.toml
@@ -10,7 +10,7 @@ path = "lib.rs"
 doctest = false
 
 [dependencies]
-serialize = { path = "../libserialize" }
+rustc_serialize = { path = "../libserialize", package = "serialize" }
 rustc_macros = { path = "../librustc_macros" }
 rustc_data_structures = { path = "../librustc_data_structures" }
 arena = { path = "../libarena" }
diff --git a/src/libsyntax_pos/hygiene.rs b/src/libsyntax_pos/hygiene.rs
index 944b1da36d038..a96e5ef2323ee 100644
--- a/src/libsyntax_pos/hygiene.rs
+++ b/src/libsyntax_pos/hygiene.rs
@@ -30,7 +30,7 @@ use crate::{Span, DUMMY_SP};
 use crate::edition::Edition;
 use crate::symbol::{kw, Symbol};
 
-use serialize::{Encodable, Decodable, Encoder, Decoder};
+use rustc_serialize::{Encodable, Decodable, Encoder, Decoder};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::Lrc;
 use std::fmt;
diff --git a/src/libsyntax_pos/lib.rs b/src/libsyntax_pos/lib.rs
index b9a062c0765f0..e5f0892b37be8 100644
--- a/src/libsyntax_pos/lib.rs
+++ b/src/libsyntax_pos/lib.rs
@@ -19,10 +19,7 @@
 #![feature(specialization)]
 #![feature(step_trait)]
 
-use serialize::{Encodable, Decodable, Encoder, Decoder};
-
-#[allow(unused_extern_crates)]
-extern crate serialize as rustc_serialize; // used by deriving
+use rustc_serialize::{Encodable, Decodable, Encoder, Decoder};
 
 pub mod edition;
 use edition::Edition;
@@ -594,7 +591,7 @@ impl Default for Span {
     }
 }
 
-impl serialize::UseSpecializedEncodable for Span {
+impl rustc_serialize::UseSpecializedEncodable for Span {
     fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
         let span = self.data();
         s.emit_struct("Span", 2, |s| {
@@ -609,7 +606,7 @@ impl serialize::UseSpecializedEncodable for Span {
     }
 }
 
-impl serialize::UseSpecializedDecodable for Span {
+impl rustc_serialize::UseSpecializedDecodable for Span {
     fn default_decode<D: Decoder>(d: &mut D) -> Result<Span, D::Error> {
         d.read_struct("Span", 2, |d| {
             let lo = d.read_struct_field("lo", 0, Decodable::decode)?;
diff --git a/src/libsyntax_pos/symbol.rs b/src/libsyntax_pos/symbol.rs
index f23ed7371c6dc..308f7d5d4e3fb 100644
--- a/src/libsyntax_pos/symbol.rs
+++ b/src/libsyntax_pos/symbol.rs
@@ -7,7 +7,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::indexed_vec::Idx;
 use rustc_data_structures::newtype_index;
 use rustc_macros::symbols;
-use serialize::{Decodable, Decoder, Encodable, Encoder};
+use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
 
 use std::cmp::{PartialEq, Ordering, PartialOrd, Ord};
 use std::fmt;

From 1aeadcc0d560fd4ce88e2c5dfd98484c2443018b Mon Sep 17 00:00:00 2001
From: Josh Stone <jistone@redhat.com>
Date: Tue, 23 Jul 2019 12:04:31 -0700
Subject: [PATCH 36/40] Require a value for configure --debuginfo-level

In `configure.py`, using the `o` function creates an enable/disable
boolean setting, and writes `true` or `false` in `config.toml`. However,
rustbuild is expecting to parse a `u32` debuginfo level. We can change
to the `v` function to have the options require a value.
---
 src/bootstrap/configure.py | 10 +++++-----
 src/ci/run.sh              |  2 +-
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/bootstrap/configure.py b/src/bootstrap/configure.py
index 53d3dbf60d1d7..907983d43ade7 100755
--- a/src/bootstrap/configure.py
+++ b/src/bootstrap/configure.py
@@ -76,11 +76,11 @@ def v(*args):
 o("llvm-assertions", "llvm.assertions", "build LLVM with assertions")
 o("debug-assertions", "rust.debug-assertions", "build with debugging assertions")
 o("llvm-release-debuginfo", "llvm.release-debuginfo", "build LLVM with debugger metadata")
-o("debuginfo-level", "rust.debuginfo-level", "debuginfo level for Rust code")
-o("debuginfo-level-rustc", "rust.debuginfo-level-rustc", "debuginfo level for the compiler")
-o("debuginfo-level-std", "rust.debuginfo-level-std", "debuginfo level for the standard library")
-o("debuginfo-level-tools", "rust.debuginfo-level-tools", "debuginfo level for the tools")
-o("debuginfo-level-tests", "rust.debuginfo-level-tests", "debuginfo level for the test suites run with compiletest")
+v("debuginfo-level", "rust.debuginfo-level", "debuginfo level for Rust code")
+v("debuginfo-level-rustc", "rust.debuginfo-level-rustc", "debuginfo level for the compiler")
+v("debuginfo-level-std", "rust.debuginfo-level-std", "debuginfo level for the standard library")
+v("debuginfo-level-tools", "rust.debuginfo-level-tools", "debuginfo level for the tools")
+v("debuginfo-level-tests", "rust.debuginfo-level-tests", "debuginfo level for the test suites run with compiletest")
 v("save-toolstates", "rust.save-toolstates", "save build and test status of external tools into this file")
 
 v("prefix", "install.prefix", "set installation prefix")
diff --git a/src/ci/run.sh b/src/ci/run.sh
index 1039343827d87..f1eb417cdf982 100755
--- a/src/ci/run.sh
+++ b/src/ci/run.sh
@@ -50,7 +50,7 @@ if [ "$DEPLOY$DEPLOY_ALT" = "1" ]; then
   RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --release-channel=$RUST_RELEASE_CHANNEL"
   RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-llvm-static-stdcpp"
   RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.remap-debuginfo"
-  RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.debuginfo-level-std=1"
+  RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --debuginfo-level-std=1"
 
   if [ "$NO_LLVM_ASSERTIONS" = "1" ]; then
     RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --disable-llvm-assertions"

From a4ff823f5d7205a983461063d08902986c11d00d Mon Sep 17 00:00:00 2001
From: Scott Wolchok <swolchok@fb.com>
Date: Tue, 23 Jul 2019 13:37:17 -0700
Subject: [PATCH 37/40] fix check

---
 src/librustc_target/spec/apple_ios_base.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/librustc_target/spec/apple_ios_base.rs b/src/librustc_target/spec/apple_ios_base.rs
index 40cc7f420106b..d400bc62bfd07 100644
--- a/src/librustc_target/spec/apple_ios_base.rs
+++ b/src/librustc_target/spec/apple_ios_base.rs
@@ -1,5 +1,6 @@
 use std::env;
 use std::io;
+use std::path::Path;
 use std::process::Command;
 use crate::spec::{LinkArgs, LinkerFlavor, TargetOptions};
 
@@ -29,7 +30,7 @@ impl Arch {
 
 pub fn get_sdk_root(sdk_name: &str) -> Result<String, String> {
     if let Some(sdkroot) = env::var("SDKROOT").ok() {
-        let sdkroot_path = Path::new(sdkroot);
+        let sdkroot_path = Path::new(&sdkroot);
         if sdkroot_path.is_absolute() && sdkroot_path != Path::new("/") && sdkroot_path.exists() {
             return Ok(sdkroot);
         }

From eafb42dc94b191fdd9f38b548f624184101182a2 Mon Sep 17 00:00:00 2001
From: Mark Rousskov <mark.simulacrum@gmail.com>
Date: Mon, 10 Jun 2019 10:18:53 -0600
Subject: [PATCH 38/40] Add binary dependencies to dep-info files

---
 src/librustc_interface/passes.rs | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/src/librustc_interface/passes.rs b/src/librustc_interface/passes.rs
index 6bf56bf851553..469215563ac39 100644
--- a/src/librustc_interface/passes.rs
+++ b/src/librustc_interface/passes.rs
@@ -9,6 +9,7 @@ use rustc::hir::lowering::lower_crate;
 use rustc::hir::def_id::{CrateNum, LOCAL_CRATE};
 use rustc::lint;
 use rustc::middle::{self, reachable, resolve_lifetime, stability};
+use rustc::middle::cstore::CrateStore;
 use rustc::middle::privacy::AccessLevels;
 use rustc::ty::{self, AllArenas, Resolutions, TyCtxt, GlobalCtxt};
 use rustc::ty::steal::Steal;
@@ -657,7 +658,8 @@ fn escape_dep_filename(filename: &FileName) -> String {
     filename.to_string().replace(" ", "\\ ")
 }
 
-fn write_out_deps(sess: &Session, outputs: &OutputFilenames, out_filenames: &[PathBuf]) {
+fn write_out_deps(compiler: &Compiler, outputs: &OutputFilenames, out_filenames: &[PathBuf]) {
+    let sess = &compiler.sess;
     // Write out dependency rules to the dep-info file if requested
     if !sess.opts.output_types.contains_key(&OutputType::DepInfo) {
         return;
@@ -667,13 +669,28 @@ fn write_out_deps(sess: &Session, outputs: &OutputFilenames, out_filenames: &[Pa
     let result = (|| -> io::Result<()> {
         // Build a list of files used to compile the output and
         // write Makefile-compatible dependency rules
-        let files: Vec<String> = sess.source_map()
+        let mut files: Vec<String> = sess.source_map()
             .files()
             .iter()
             .filter(|fmap| fmap.is_real_file())
             .filter(|fmap| !fmap.is_imported())
             .map(|fmap| escape_dep_filename(&fmap.name))
             .collect();
+
+        for cnum in compiler.cstore.crates_untracked() {
+            let metadata = compiler.cstore.crate_data_as_rc_any(cnum);
+            let metadata = metadata.downcast_ref::<cstore::CrateMetadata>().unwrap();
+            if let Some((path, _)) = &metadata.source.dylib {
+                files.push(escape_dep_filename(&FileName::Real(path.clone())));
+            }
+            if let Some((path, _)) = &metadata.source.rlib {
+                files.push(escape_dep_filename(&FileName::Real(path.clone())));
+            }
+            if let Some((path, _)) = &metadata.source.rmeta {
+                files.push(escape_dep_filename(&FileName::Real(path.clone())));
+            }
+        }
+
         let mut file = fs::File::create(&deps_filename)?;
         for path in out_filenames {
             writeln!(file, "{}: {}\n", path.display(), files.join(" "))?;
@@ -750,7 +767,7 @@ pub fn prepare_outputs(
         }
     }
 
-    write_out_deps(sess, &outputs, &output_paths);
+    write_out_deps(compiler, &outputs, &output_paths);
 
     let only_dep_info = sess.opts.output_types.contains_key(&OutputType::DepInfo)
         && sess.opts.output_types.len() == 1;

From d749b5e2237abdb79494afc9c8d7c8280db9088c Mon Sep 17 00:00:00 2001
From: Mark Rousskov <mark.simulacrum@gmail.com>
Date: Wed, 24 Jul 2019 11:00:09 -0400
Subject: [PATCH 39/40] Gate binary dependency information behind
 -Zbinary-dep-depinfo

---
 src/librustc/session/config.rs   |  2 ++
 src/librustc/session/mod.rs      |  3 +++
 src/librustc_interface/passes.rs | 24 +++++++++++++-----------
 3 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/src/librustc/session/config.rs b/src/librustc/session/config.rs
index 470a08fad23b5..9a8429733d103 100644
--- a/src/librustc/session/config.rs
+++ b/src/librustc/session/config.rs
@@ -1468,6 +1468,8 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,
     symbol_mangling_version: SymbolManglingVersion = (SymbolManglingVersion::Legacy,
         parse_symbol_mangling_version, [TRACKED],
         "which mangling version to use for symbol names"),
+    binary_dep_depinfo: bool = (false, parse_bool, [TRACKED],
+        "include artifacts (sysroot, crate dependencies) used during compilation in dep-info"),
 }
 
 pub fn default_lib_output() -> CrateType {
diff --git a/src/librustc/session/mod.rs b/src/librustc/session/mod.rs
index 664926a152f14..c88ca132184b2 100644
--- a/src/librustc/session/mod.rs
+++ b/src/librustc/session/mod.rs
@@ -545,6 +545,9 @@ impl Session {
     pub fn print_llvm_passes(&self) -> bool {
         self.opts.debugging_opts.print_llvm_passes
     }
+    pub fn binary_dep_depinfo(&self) -> bool {
+        self.opts.debugging_opts.binary_dep_depinfo
+    }
 
     /// Gets the features enabled for the current compilation session.
     /// DO NOT USE THIS METHOD if there is a TyCtxt available, as it circumvents
diff --git a/src/librustc_interface/passes.rs b/src/librustc_interface/passes.rs
index 469215563ac39..772395bca2b37 100644
--- a/src/librustc_interface/passes.rs
+++ b/src/librustc_interface/passes.rs
@@ -677,17 +677,19 @@ fn write_out_deps(compiler: &Compiler, outputs: &OutputFilenames, out_filenames:
             .map(|fmap| escape_dep_filename(&fmap.name))
             .collect();
 
-        for cnum in compiler.cstore.crates_untracked() {
-            let metadata = compiler.cstore.crate_data_as_rc_any(cnum);
-            let metadata = metadata.downcast_ref::<cstore::CrateMetadata>().unwrap();
-            if let Some((path, _)) = &metadata.source.dylib {
-                files.push(escape_dep_filename(&FileName::Real(path.clone())));
-            }
-            if let Some((path, _)) = &metadata.source.rlib {
-                files.push(escape_dep_filename(&FileName::Real(path.clone())));
-            }
-            if let Some((path, _)) = &metadata.source.rmeta {
-                files.push(escape_dep_filename(&FileName::Real(path.clone())));
+        if sess.binary_dep_depinfo() {
+            for cnum in compiler.cstore.crates_untracked() {
+                let metadata = compiler.cstore.crate_data_as_rc_any(cnum);
+                let metadata = metadata.downcast_ref::<cstore::CrateMetadata>().unwrap();
+                if let Some((path, _)) = &metadata.source.dylib {
+                    files.push(escape_dep_filename(&FileName::Real(path.clone())));
+                }
+                if let Some((path, _)) = &metadata.source.rlib {
+                    files.push(escape_dep_filename(&FileName::Real(path.clone())));
+                }
+                if let Some((path, _)) = &metadata.source.rmeta {
+                    files.push(escape_dep_filename(&FileName::Real(path.clone())));
+                }
             }
         }
 

From 287db19e9a480decb491d39c3c22357a7a68f102 Mon Sep 17 00:00:00 2001
From: Scott Wolchok <swolchok@fb.com>
Date: Wed, 24 Jul 2019 10:28:14 -0700
Subject: [PATCH 40/40] Add comment

---
 src/librustc_target/spec/apple_ios_base.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/librustc_target/spec/apple_ios_base.rs b/src/librustc_target/spec/apple_ios_base.rs
index d400bc62bfd07..f46ad06ba436a 100644
--- a/src/librustc_target/spec/apple_ios_base.rs
+++ b/src/librustc_target/spec/apple_ios_base.rs
@@ -29,6 +29,12 @@ impl Arch {
 }
 
 pub fn get_sdk_root(sdk_name: &str) -> Result<String, String> {
+    // Following what clang does
+    // (https://github.com/llvm/llvm-project/blob/
+    // 296a80102a9b72c3eda80558fb78a3ed8849b341/clang/lib/Driver/ToolChains/Darwin.cpp#L1661-L1678)
+    // to allow the SDK path to be set. (For clang, xcrun sets
+    // SDKROOT; for rustc, the user or build system can set it, or we
+    // can fall back to checking for xcrun on PATH.)
     if let Some(sdkroot) = env::var("SDKROOT").ok() {
         let sdkroot_path = Path::new(&sdkroot);
         if sdkroot_path.is_absolute() && sdkroot_path != Path::new("/") && sdkroot_path.exists() {