Fix more aspects of the NaCl build 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")
 if (current_cpu == "arm") {
   import("//build/config/arm.gni")
 }
 if (current_cpu == "mipsel" || current_cpu == "mips64el") {
@@ skipping 504 matching lines @@
   }
 
   # Clang-specific compiler flags setup.
   # ------------------------------------
   if (is_clang) {
     cflags += [ "-fcolor-diagnostics" ]
   }
 
   # C++11 compiler flags setup.
   # ---------------------------
-  if (is_linux || is_android || is_nacl) {
+  if (is_linux || is_android || (is_nacl && is_clang)) {

[Nico, 2015/09/05 01:03:20]

I still don't understand this change. Why is this depending on clang?

From what I understand, this probably corresponds to
https://code.google.com/p/chromium/codesearch#chromium/src/native_client/buil...
– should this just say

 if (is_nacl)
   gnu++0x  # nacl toolchain is old
  else if /* as before */

?

[Dirk Pranke, 2015/09/05 01:37:20]

the clang-based NaCl toolchains understand this flag. the gcc-based ones do not.

We need the flag in some places to compile some of the code (like the irt), but
we don't 
need it everywhere (apparently).

Does that help clarify things?
Yes, that might work. The code, however, compiles just fine w/ no --std= flag at
all, too.

     # gnu++11 instead of c++11 is needed because some code uses typeof() (a
     # GNU extension).
     # TODO(thakis): Eventually switch this to c++11 instead,
     # http://crbug.com/427584
     cflags_cc += [ "-std=gnu++11" ]
-  } else if (!is_win) {
+  } else if (!is_win && !is_nacl) {
+    # TODO(mcgrathr) - the NaCl GCC toolchain doesn't support either gnu++11
+    # or c++11; we technically don't need this toolchain any more, but there
+    # are still a few buildbots using it, so until those are turned off
+    # we need the !is_nacl clause and the (is_nacl && is_clang) clause, above.
     cflags_cc += [ "-std=c++11" ]
   }
 
   # Android-specific flags setup.
   # -----------------------------
   if (is_android) {
     cflags += [
       "-ffunction-sections",
       "-funwind-tables",
       "-fno-short-enums",
@@ skipping 800 matching lines @@
       cflags += [ "-gsplit-dwarf" ]
     }
   }
 }
 
 config("no_symbols") {
   if (!is_win) {
     cflags = [ "-g0" ]
   }
 }