Mov Linux & Mac GN compiler flags to separate configs.

build/config/compiler/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/config/android/config.gni")
 import("//build/config/chrome_build.gni")
 import("//build/config/compiler/compiler.gni")
 import("//build/toolchain/ccache.gni")
 
 if (current_cpu == "arm") {
@@ skipping 92 matching lines @@
   defines = []
   configs = []
 
   # System-specific flags. If your compiler flags apply to one of the
   # categories here, add it to the associated file to keep this shared config
   # smaller.
   if (is_win) {
     configs += [ "//build/config/win:compiler" ]
   } else if (is_android) {
     configs += [ "//build/config/android:compiler" ]
+  } else if (is_linux) {
+    configs += [ "//build/config/linux:compiler" ]
   }
 
   # In general, Windows is totally different, but all the other builds share
   # some common GCC configuration.
   if (!is_win) {
     # Common GCC compiler flags setup.
     # --------------------------------
     cflags += [ "-fno-strict-aliasing" ]  # See http://crbug.com/32204
     cflags_cc += [
       "-fno-threadsafe-statics",
@@ skipping 42 matching lines @@
     # This is here so that all files get recompiled after a clang roll and
     # when turning clang on or off. (defines are passed via the command line,
     # and build system rebuild things when their commandline changes). Nothing
     # should ever read this define.
     defines +=
         [ "CR_CLANG_REVISION=" + exec_script("//tools/clang/scripts/update.py",
                                              [ "--print-revision" ],
                                              "trim string") ]
   }
 
-  # Mac-specific compiler flags setup.
-  # ----------------------------------
-  if (is_mac || is_ios) {
-    # These flags are shared between the C compiler and linker.
-    common_mac_flags = []
-
-    # CPU architecture.
-    if (current_cpu == "x64") {
-      common_mac_flags += [
-        "-arch",
-        "x86_64",
-      ]
-    } else if (current_cpu == "x86") {
-      common_mac_flags += [
-        "-arch",
-        "i386",
-      ]
-    } else if (current_cpu == "arm") {
-      # TODO(GYP): we may need to distinguish between "arm64", "armv7",
-      # and "armv7s" for iOS, and hence need multiple current_cpu values
-      # rather than just "arm".
-      common_mac_flags += [
-        "-arch",
-        "arm64",
-      ]
-    }
-
-    cflags += common_mac_flags
-
-    # Without this, the constructors and destructors of a C++ object inside
-    # an Objective C struct won't be called, which is very bad.
-    cflags_objcc += [ "-fobjc-call-cxx-cdtors" ]
-
-    cflags_c += [ "-std=c99" ]
-
-    ldflags += common_mac_flags
-  } else if (is_posix) {
-    # Non-Mac Posix compiler flags setup.
-    # -----------------------------------
+  # Non-Mac Posix compiler flags setup.
+  # -----------------------------------
+  if (is_posix && !(is_mac || is_ios)) {
     if (enable_profiling && !is_debug) {
       # The GYP build spams this define into every compilation unit, as we do
       # here, but it only appears to be used in base and a couple other places.
       # TODO(abarth): Should we move this define closer to where it's used?
       defines += [ "ENABLE_PROFILING" ]
 
       cflags += [
         "-fno-omit-frame-pointer",
         "-g",
       ]
@@ skipping 160 matching lines @@
       "-Wl,-z,now",
       "-Wl,-z,relro",
     ]
     if (!using_sanitizer && !use_cfi_diag) {
       ldflags += [ "-Wl,-z,defs" ]
     }
   }
 
   # Linux-specific compiler flags setup.
   # ------------------------------------
-  if (is_linux) {
-    cflags += [ "-pthread" ]
-    ldflags += [ "-pthread" ]
-  }
   if (use_gold) {
     ldflags += [
       "-B$gold_path",
 
       # Newer gccs and clangs support -fuse-ld, use the flag to force gold
       # selection.
       # gcc -- http://gcc.gnu.org/onlinedocs/gcc-4.8.0/gcc/Optimize-Options.html
       "-fuse-ld=gold",
 
       # Experimentation found that using four linking threads
@@ skipping 743 matching lines @@
   if (symbol_level == 0) {
     configs = [ ":no_symbols" ]
   } else if (symbol_level == 1) {
     configs = [ ":minimal_symbols" ]
   } else if (symbol_level == 2) {
     configs = [ ":symbols" ]
   } else {
     assert(false)
   }
 }