GN: Add -Wl,-z defs on linux and fix errors

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")
 if (cpu_arch == "arm") {
   import("//build/config/arm.gni")
 }
 if (is_posix) {
   import("//build/config/gcc/gcc_version.gni")
@@ skipping 283 matching lines @@
     cflags += [
       "-fPIC",
       "-pipe",  # Use pipes for communicating between sub-processes. Faster.
     ]
 
     ldflags += [
       "-fPIC",
       "-Wl,-z,noexecstack",
       "-Wl,-z,now",
       "-Wl,-z,relro",
+      "-Wl,-z,defs",

[Nico, 2015/01/15 23:35:07]

Did you try an android build?

     ]
   }
 
   # Linux-specific compiler flags setup.
   # ------------------------------------
   if (is_linux) {
     cflags += [ "-pthread" ]
     ldflags += [ "-pthread" ]
   }
   if (use_gold) {
@@ skipping 672 matching lines @@
       cflags += [ "-gsplit-dwarf" ]
     }
   }
 }
 
 config("no_symbols") {
   if (!is_win) {
     cflags = [ "-g0" ]
   }
 }