Fix tcmalloc arm clang build

base/allocator/BUILD.gn

 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/buildflag_header.gni")
 import("//build/config/allocator.gni")
 import("//build/config/compiler/compiler.gni")
 
 declare_args() {
   # Provide a way to force disable debugallocation in Debug builds,
@@ skipping 55 matching lines @@
       "-Wno-unused-function",
 
       # tcmalloc uses COMPILE_ASSERT without static_assert but with
       # typedefs.
       "-Wno-unused-local-typedefs",
 
       # for magic2_ in debugallocation.cc (only built in Debug builds)
       # typedefs.
       "-Wno-unused-private-field",
     ]
+    if (target_cpu == "arm") {
+      # Temporarily disable clang's integrated assembler when building tcmalloc
+      # TODO(https://llvm.org/bugs/show_bug.cgi?id=31058)
+      cflags += [ "-fno-integrated-as" ]

[llozano, 2016/11/22 19:42:53]

I thought the option is -no-integrated-as but this also works for some reason.
I think it is better to just use -no-integrated-as. That is how I find it in the
documentation...

+    }
   } else {
     cflags = []
   }
 
   if (is_linux || is_android) {
     # We enable all warnings by default, but upstream disables a few.
     # Keep "-Wno-*" flags in sync with upstream by comparing against:
     # http://code.google.com/p/google-perftools/source/browse/trunk/Makefile.am
     cflags += [
       "-Wno-sign-compare",
@@ skipping 123 matching lines @@
 
     # Disable the heap checker in tcmalloc.
     defines = [ "NO_HEAP_CHECK" ]
 
     include_dirs = [
       ".",
       "$tcmalloc_dir/src/base",
       "$tcmalloc_dir/src",
     ]
 
-    configs -= [
-      "//build/config/compiler:chromium_code",
-
-      # Thumb mode disabled due to bug in clang integrated assembler
-      # TODO(https://llvm.org/bugs/show_bug.cgi?id=31058)
-      "//build/config/compiler:compiler_arm_thumb",
-    ]
+    configs -= [ "//build/config/compiler:chromium_code" ]
     configs += [
       "//build/config/compiler:no_chromium_code",
       ":tcmalloc_flags",
     ]
 
     # TODO(crbug.com/633719) Make tcmalloc work with AFDO if possible.
     configs -= [ "//build/config/compiler:afdo" ]
 
     deps = []
 
@@ skipping 105 matching lines @@
       sources += [ "allocator_shim_default_dispatch_to_glibc.cc" ]
     } else if (is_android && use_allocator == "none") {
       sources += [
         "allocator_shim_default_dispatch_to_linker_wrapped_symbols.cc",
         "allocator_shim_override_linker_wrapped_symbols.h",
       ]
       all_dependent_configs = [ ":wrap_malloc_symbols" ]
     }
   }
 }