Inlinable function call in a function with debug info must have a !dbg location

[cschlack]

$ crystal --version

Crystal 0.21.1 (2017-03-14) LLVM 4.0.0

$ crystal spec

Module validation failed: inlinable function call in a function with debug info must have a !dbg location
  %120 = call i8* @__crystal_malloc(i32 ptrtoint (i1** getelementptr (i1*, i1** null, i32 1) to i32))

0x10c31fb33: *raise<String>:NoReturn at ??
0x10d2f0aab: *Crystal::CodeGenVisitor#finish:Nil at ??
0x10d21c37e: *Crystal::Compiler#codegen<Crystal::Program, Crystal::ASTNode+, Array(Crystal::Compiler::Source), String>:(Tuple(Array(Crystal::Compiler::CompilationUnit), Array(String)) | Nil) at ??
0x10dac1ff4: *Crystal::Compiler#compile<Array(Crystal::Compiler::Source), String>:Crystal::Compiler::Result at ??
0x10c38209a: *Crystal::Command#run:(Bool | Crystal::Compiler::Result | IO::FileDescriptor | Nil) at ??
0x10c3498bd: main at ??

Error: you've found a bug in the Crystal compiler. Please open an issue, including source code that will allow us to reproduce the bug: https://github.com/crystal-lang/crystal/issues

[cschlack]

I'm having a hard time figuring out, which code triggers this message. It does not happen in an empty project (crystal init).

Does the message above already give enough hints about the source of the issue?

If not I'm going to do more research...

[bcardiff]

@cschlack without a bit more of source code is hard to diagnose. Try to reduce as much as possible before sharing please.

If this is blocking you building with --no-debug might help.

[cschlack]

Okay, here we go:

file: test.cr

require "spec"
require "http"

test = ""

it "breaks the compiler" do
  test.empty?
end

$ crystal spec test.cr

(running on MacOS 10.11.6)

[bcardiff]

I reach this:

file: test.cr

def call(&block)
  block.call
end

test = ""

call do
  test.empty?
end

The following passes

$ crystal test.cr --debug
$ crystal test.cr --no-debug

But given a test_main.cr file with

require "./test"

$ crystal build test_main.cr --debug
Module validation failed: inlinable function call in a function with debug info must have a !dbg location
  %73 = call i8* @__crystal_malloc(i32 ptrtoint (i1** getelementptr (i1*, i1** null, i32 1) to i32))

$ crystal build test_main.cr --no-debug

[bcardiff]

file: test.cr

require "lib_c"
require "c/stdlib"

fun __crystal_malloc(size : UInt32) : Void*
  LibC.malloc(size)
end

class Foo
  @p : (Void* -> Void*)?
end

def call(&block)
  block.call
end

test = 0

call do
  test
end

file: main_test.cr

require "./test"

$ DUMP=1 ./bin/crystal build test.cr --debug --prelude=empty
... ok ...
$ DUMP=1 ./bin/crystal build test_main.cr --debug --prelude=empty
....
Module validation failed: inlinable function call in a function with debug info must have a !dbg location
  %1 = call i8* @__crystal_malloc(i32 ptrtoint (i32* getelementptr (i32, i32* null, i32 1) to i32))

In the first command there are 42 debug locations and in the second command 41 debug locations. One missing :-)