bazel: patch gRPC to fix Envoy builds with glibc v2.30 (envoyproxy#7971)

Description: the latest glibc (v2.30) declares its own `gettid()` function (see [0]) and this creates a naming conflict in gRPC which has a function with the same name.

Apply to gRPC [a patch](grpc/grpc#18950) which renames `gettid()` to `sys_gettid()`.

[0] https://sourceware.org/git/?p=glibc.git;a=commit;h=1d0fc213824eaa2a8f8c4385daaa698ee8fb7c92

Risk Level: low
Testing: unit tests
Docs Changes: n/a
Release Notes: n/a

Signed-off-by: Dmitry Rozhkov <[email protected]>

bazel/grpc-rename-gettid.patch

@@ -0,0 +1,78 @@
+From d1d017390b799c59d6fdf7b8afa6136d218bdd61 Mon Sep 17 00:00:00 2001
+From: Benjamin Peterson <[email protected]>
+Date: Fri, 3 May 2019 08:11:00 -0700
+Subject: [PATCH] Rename gettid() functions.
+
+glibc 2.30 will declare its own gettid; see https://sourceware.org/git/?p=glibc.git;a=commit;h=1d0fc213824eaa2a8f8c4385daaa698ee8fb7c92. Rename the grpc versions to avoid naming conflicts.
+---
+ src/core/lib/gpr/log_linux.cc          | 4 ++--
+ src/core/lib/gpr/log_posix.cc          | 4 ++--
+ src/core/lib/iomgr/ev_epollex_linux.cc | 4 ++--
+ 3 files changed, 6 insertions(+), 6 deletions(-)
+
+diff --git a/src/core/lib/gpr/log_linux.cc b/src/core/lib/gpr/log_linux.cc
+index 561276f0c20..8b597b4cf2f 100644
+--- a/src/core/lib/gpr/log_linux.cc
++++ b/src/core/lib/gpr/log_linux.cc
+@@ -40,7 +40,7 @@
+ #include <time.h>
+ #include <unistd.h>
+
+-static long gettid(void) { return syscall(__NR_gettid); }
++static long sys_gettid(void) { return syscall(__NR_gettid); }
+
+ void gpr_log(const char* file, int line, gpr_log_severity severity,
+              const char* format, ...) {
+@@ -70,7 +70,7 @@ void gpr_default_log(gpr_log_func_args* args) {
+   gpr_timespec now = gpr_now(GPR_CLOCK_REALTIME);
+   struct tm tm;
+   static __thread long tid = 0;
+-  if (tid == 0) tid = gettid();
++  if (tid == 0) tid = sys_gettid();
+
+   timer = static_cast<time_t>(now.tv_sec);
+   final_slash = strrchr(args->file, '/');
+diff --git a/src/core/lib/gpr/log_posix.cc b/src/core/lib/gpr/log_posix.cc
+index b6edc14ab6b..2f7c6ce3760 100644
+--- a/src/core/lib/gpr/log_posix.cc
++++ b/src/core/lib/gpr/log_posix.cc
+@@ -31,7 +31,7 @@
+ #include <string.h>
+ #include <time.h>
+
+-static intptr_t gettid(void) { return (intptr_t)pthread_self(); }
++static intptr_t sys_gettid(void) { return (intptr_t)pthread_self(); }
+
+ void gpr_log(const char* file, int line, gpr_log_severity severity,
+              const char* format, ...) {
+@@ -86,7 +86,7 @@ void gpr_default_log(gpr_log_func_args* args) {
+   char* prefix;
+   gpr_asprintf(&prefix, "%s%s.%09d %7" PRIdPTR " %s:%d]",
+                gpr_log_severity_string(args->severity), time_buffer,
+-               (int)(now.tv_nsec), gettid(), display_file, args->line);
++               (int)(now.tv_nsec), sys_gettid(), display_file, args->line);
+
+   fprintf(stderr, "%-70s %s\n", prefix, args->message);
+   gpr_free(prefix);
+diff --git a/src/core/lib/iomgr/ev_epollex_linux.cc b/src/core/lib/iomgr/ev_epollex_linux.cc
+index 08116b3ab53..76f59844312 100644
+--- a/src/core/lib/iomgr/ev_epollex_linux.cc
++++ b/src/core/lib/iomgr/ev_epollex_linux.cc
+@@ -1102,7 +1102,7 @@ static void end_worker(grpc_pollset* pollset, grpc_pollset_worker* worker,
+ }
+
+ #ifndef NDEBUG
+-static long gettid(void) { return syscall(__NR_gettid); }
++static long sys_gettid(void) { return syscall(__NR_gettid); }
+ #endif
+
+ /* pollset->mu lock must be held by the caller before calling this.
+@@ -1122,7 +1122,7 @@ static grpc_error* pollset_work(grpc_pollset* pollset,
+ #define WORKER_PTR (&worker)
+ #endif
+ #ifndef NDEBUG
+-  WORKER_PTR->originator = gettid();
++  WORKER_PTR->originator = sys_gettid();
+ #endif
+   if (GRPC_TRACE_FLAG_ENABLED(grpc_polling_trace)) {
+     gpr_log(GPR_INFO,

bazel/repositories.bzl

@@ -617,6 +617,8 @@ def _com_github_grpc_grpc():
             "@envoy//bazel:grpc-protoinfo-2.patch",
             # Pre-integration of https://github.com/grpc/grpc/pull/19860
             "@envoy//bazel:grpc-protoinfo-3.patch",
+            # Pre-integration of https://github.com/grpc/grpc/pull/18950
+            "@envoy//bazel:grpc-rename-gettid.patch",
         ],
         patch_args = ["-p1"],
     )