Create a build_config header file.

SConstruct

Index: SConstruct
diff --git a/SConstruct b/SConstruct
index 609af9513043ec432fdf1f8fa1dd7907206b35ed..5b7f5c8f4620bfc4f7b3b0c5f580e8bd2ab05f61 100755
--- a/SConstruct
+++ b/SConstruct
@@ -2142,13 +2142,6 @@ that the given target requires that argument be given."""
 pre_base_env.AddMethod(GetAbsDirArg)
 
 
-pre_base_env.Append(
-    CPPDEFINES = [
-        ['NACL_BUILD_ARCH', '${BUILD_ARCHITECTURE}' ],
-        ['NACL_BUILD_SUBARCH', '${BUILD_SUBARCH}' ],
-        ],
-    )
-
 def MakeGTestEnv(env):
   # Create an environment to run unit tests using Gtest.
   gtest_env = env.Clone()
@@ -2450,10 +2443,6 @@ def MakeWindowsEnv(platform=None):
 
   windows_env.Append(
       CPPDEFINES = [
-          ['NACL_WINDOWS', '1'],
-          ['NACL_OSX', '0'],
-          ['NACL_LINUX', '0'],
-          ['NACL_ANDROID', '0'],
           ['_WIN32_WINNT', '0x0501'],
           ['__STDC_LIMIT_MACROS', '1'],
           ['NOMINMAX', '1'],
@@ -2467,7 +2456,8 @@ def MakeWindowsEnv(platform=None):
       LIBS = ['ws2_32', 'advapi32'],
       # TODO(bsy) remove 4355 once cross-repo
       # NACL_ALLOW_THIS_IN_INITIALIZER_LIST changes go in.
-      CCFLAGS = ['/EHsc', '/WX', '/wd4355', '/wd4800'],
+      CCFLAGS = ['/EHsc', '/WX', '/wd4355', '/wd4800', '/FI',
+                 '$SOURCE_ROOT/native_client/src/include/build_config.h']

[Mark Seaborn, 2014/12/19 17:46:19]

Can you put '/FI' on the same line as this, to make it clear they go together?

Also, how about commenting why this is injected?

Can you add the "-include" for:

 * Linux/Mac
 * Gyp builds (via build/common.gypi)

I'd like to make sure this works in all these cases.

   )
 
   # This linker option allows us to ensure our builds are compatible with
@@ -2578,6 +2568,8 @@ def MakeMacEnv(platform=None):
                     ['NACL_OSX', '1'],
                     ['NACL_LINUX', '0'],
                     ['NACL_ANDROID', '0'],
+                    ['NACL_BUILD_ARCH', '${BUILD_ARCHITECTURE}' ],
+                    ['NACL_BUILD_SUBARCH', '${BUILD_SUBARCH}' ],
                     # defining _DARWIN_C_SOURCE breaks 10.4
                     #['_DARWIN_C_SOURCE', '1'],
                     #['__STDC_LIMIT_MACROS', '1']
@@ -2800,11 +2792,7 @@ def MakeGenericLinuxEnv(platform=None):
 
   # Prepend so we can disable warnings via Append
   linux_env.Prepend(
-      CPPDEFINES = [['NACL_WINDOWS', '0'],
-                    ['NACL_OSX', '0'],
-                    ['NACL_LINUX', '1'],
-                    ['NACL_ANDROID', '0'],
-                    ['_DEFAULT_SOURCE', '1'],
+      CPPDEFINES = [['_DEFAULT_SOURCE', '1'],
                     ['_BSD_SOURCE', '1'],
                     ['_POSIX_C_SOURCE', '199506'],
                     ['_XOPEN_SOURCE', '600'],
@@ -3118,6 +3106,8 @@ nacl_env.Append(
         ['NACL_OSX', '0'],
         ['NACL_LINUX', '0'],
         ['NACL_ANDROID', '0'],
+        ['NACL_BUILD_ARCH', '${BUILD_ARCHITECTURE}' ],
+        ['NACL_BUILD_SUBARCH', '${BUILD_SUBARCH}' ],
         ],
     )
 
@@ -3481,8 +3471,6 @@ def RawSyscallObjects(env, sources):
   raw_syscall_env.Append(
     CPPDEFINES = [
       ['USE_RAW_SYSCALLS', '1'],
-      ['NACL_BUILD_ARCH', '${BUILD_ARCHITECTURE}' ],
-      ['NACL_BUILD_SUBARCH', '${BUILD_SUBARCH}' ],
       ],
   )
   objects = []