Create a build_config header file.

SConstruct

 #! -*- python -*-
 # Copyright (c) 2012 The Native Client 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 atexit
 import json
 import os
 import platform
 import re
@@ skipping 2124 matching lines @@
 directory name.  If the argument is missing, raise a UserError saying
 that the given target requires that argument be given."""
   dir = ARGUMENTS.get(argument)
   if not dir:
     raise UserError('%s must be set when invoking %s' % (argument, target))
   return os.path.join(env.Dir('$MAIN_DIR').abspath, dir)
 
 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()
 
   # This became necessary for the arm cross TC v4.6
   # but probable applies to all new gcc TCs
   gtest_env.Append(LINKFLAGS=['-pthread'])
 
   # Define compile-time flag that communicates that we are compiling in the test
   # environment (rather than for the TCB).
@@ skipping 281 matching lines @@
                '$WINASM -defsym @feat.00=1 -o $TARGET'),
       PDB = '${TARGET.base}.pdb',
       # Strict doesn't currently work for Windows since some of the system
       # libraries like wsock32 are magical.
       LIBS_STRICT = False,
       TARGET_ARCH='x86_64' if base_env.Bit('build_x86_64') else 'x86',
   )
 
   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'],
           # WIN32 is used by ppapi
           ['WIN32', '1'],
           # WIN32_LEAN_AND_MEAN tells windows.h to omit obsolete and rarely
           # used #include files. This allows use of Winsock 2.0 which otherwise
           # would conflict with Winsock 1.x included by windows.h.
           ['WIN32_LEAN_AND_MEAN', ''],
       ],
       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',
+                  # build_config.h is injected as a header in all sources to

[Mark Seaborn, 2014/12/29 17:51:03]

Nit: indent by 1 space less

[teravest, 2014/12/29 22:29:28]

Done.

+                  # provide macro definitions for the operating system and
+                  # architecture. This is injected so it's never accidentally
+                  # omitted in source files.
+                 '/FI', '$SOURCE_ROOT/native_client/src/include/build_config.h']
   )
 
   # This linker option allows us to ensure our builds are compatible with
   # Chromium, which uses it.
   if windows_env.Bit('build_x86_32'):
     windows_env.Append(LINKFLAGS = "/safeseh")
 
   # We use the GNU assembler (gas) on Windows so that we can use the
   # same .S assembly files on all platforms.  Microsoft's assembler uses
   # a completely different syntax for x86 code.
@@ skipping 35 matching lines @@
         '-Wall',
         '-pedantic',
         '-Wextra',
         '-Wno-long-long',
         '-Wswitch-enum',
         '-Wsign-compare',
         '-Wundef',
         '-fdiagnostics-show-option',
         '-fvisibility=hidden',
         '-fstack-protector',
+        # build_config.h is injected as a header in all sources to provide
+        # macro definitions for the operating system and architecture. This is
+        # injected so it's never accidentally omitted in source files.
+        '-include', '$SOURCE_ROOT/native_client/src/include/build_config.h',
         ] + werror_flags,
     # NOTE: pthread is only neeeded for libppNaClPlugin.so and on arm
     LIBS = ['pthread'],
     CPPDEFINES = [['__STDC_LIMIT_MACROS', '1'],
                   ['__STDC_FORMAT_MACROS', '1'],
                   ],
   )
   # Android's stlport uses __STRICT_ANSI__ to exclude "long long".
   # This breaks basically all C++ code that uses stlport.
   if not unix_like_env.Bit('android'):
@@ skipping 31 matching lines @@
 
   mac_env.Append(
       CCFLAGS=['-mmacosx-version-min=' + mac_deployment_target],
       LINKFLAGS=['-mmacosx-version-min=' + mac_deployment_target])
 
   subarch_flag = '-m%s' % mac_env['BUILD_SUBARCH']
   mac_env.Append(
       CCFLAGS=[subarch_flag, '-fPIC'],
       ASFLAGS=[subarch_flag],
       LINKFLAGS=[subarch_flag, '-fPIC'],
-      CPPDEFINES = [['NACL_WINDOWS', '0'],
-                    ['NACL_OSX', '1'],
-                    ['NACL_LINUX', '0'],
-                    ['NACL_ANDROID', '0'],
-                    # defining _DARWIN_C_SOURCE breaks 10.4
+      CPPDEFINES = [# defining _DARWIN_C_SOURCE breaks 10.4
                     #['_DARWIN_C_SOURCE', '1'],
                     #['__STDC_LIMIT_MACROS', '1']
                     ],
   )
+
   return mac_env
 
 (mac_debug_env, mac_optimized_env) = GenerateOptimizationLevels(MakeMacEnv())
 
 
 def which(cmd, paths=os.environ.get('PATH', '').split(os.pathsep)):
   for p in paths:
      if os.access(os.path.join(p, cmd), os.X_OK):
        return True
   return False
@@ skipping 197 matching lines @@
       BUILD_TYPE_DESCRIPTION = 'Linux ${OPTIMIZATION_LEVEL} build',
       tools = ['target_platform_linux'],
       # TODO(bradnelson): this should really be able to live in unix_like_env
       #                   but can't due to what the target_platform_x module is
       #                   doing.
       LINK = '$CXX',
   )
 
   # 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'],
                     ['_GNU_SOURCE', '1'],
                     ['_LARGEFILE64_SOURCE', '1'],
                     ],
       LIBS = ['rt'],
       )
 
   if linux_env.Bit('build_x86_32'):
@@ skipping 293 matching lines @@
         ['_POSIX_C_SOURCE', '199506'],
         ['_XOPEN_SOURCE', '600'],
 
         ['DYNAMIC_ANNOTATIONS_ENABLED', '1' ],
         ['DYNAMIC_ANNOTATIONS_PREFIX', 'NACL_' ],
 
         ['NACL_WINDOWS', '0'],
         ['NACL_OSX', '0'],
         ['NACL_LINUX', '0'],
         ['NACL_ANDROID', '0'],
+        ['NACL_BUILD_ARCH', '${BUILD_ARCHITECTURE}' ],

[Mark Seaborn, 2014/12/29 17:51:03]

Can you inject build_config.h for untrusted code too?

[teravest, 2014/12/29 22:29:28]

I'm getting some strange errors when doing so:
/usr/local/google/nacl_repo/native_client/src/include/build_config.h:10:49:
error: native_client/src/include/nacl_base.h: No such file or directory
/usr/local/google/nacl_repo/native_client/src/include/build_config.h:42:34:
error: "NACL_ARCH" is not defined
/usr/local/google/nacl_repo/native_client/src/include/build_config.h:42:43:
error: missing binary operator before token "("

I'm not sure why it can't find nacl_base.h in the untrusted build. There's
probably something tricky that has to happen with the includes, but I'd prefer
not to mess with the untrusted build too much.

[Mark Seaborn, 2015/01/02 04:18:31]

That is from the Scons build, right?

Does it fail like that on the trybots too, or did you only try it locally?  Can
you share the patch you tried so that I can try to debug it?

If you run Scons with --verbose, what is the command line that fails?  (I'm
wondering what "-I" arguments are passed.)

While it looks like you don't need to change the untrusted build for now (since
build_nexe.py sets NACL_BUILD_ARCH OK), I don't like mysteries like this getting
in the way of making things consistent. :-)

+        ['NACL_BUILD_SUBARCH', '${BUILD_SUBARCH}' ],
         ],
     )
 
 def FixWindowsAssembler(env):
   if env.Bit('host_windows'):
     # NOTE: This is needed because Windows builds are case-insensitive.
     # Without this we use nacl-as, which doesn't handle include directives, etc.
     env.Replace(ASCOM='${CCCOM}')
 
 FixWindowsAssembler(nacl_env)
@@ skipping 343 matching lines @@
 
 nacl_env.AddMethod(NaClSdkLibrary)
 
 
 # Special environment for untrusted test binaries that use raw syscalls
 def RawSyscallObjects(env, sources):
   raw_syscall_env = env.Clone()
   raw_syscall_env.Append(
     CPPDEFINES = [
       ['USE_RAW_SYSCALLS', '1'],
-      ['NACL_BUILD_ARCH', '${BUILD_ARCHITECTURE}' ],
-      ['NACL_BUILD_SUBARCH', '${BUILD_SUBARCH}' ],
       ],
   )
   objects = []
   for source_file in sources:
     target_name = 'raw_' + os.path.basename(source_file).rstrip('.c')
     object = raw_syscall_env.ComponentObject(target_name,
                                              source_file)
     objects.append(object)
   return objects
 
@@ skipping 548 matching lines @@
   nacl_env.ValidateSdk()
 
 if BROKEN_TEST_COUNT > 0:
   msg = "There are %d broken tests." % BROKEN_TEST_COUNT
   if GetOption('brief_comstr'):
     msg += " Add --verbose to the command line for more information."
   print msg
 
 # separate warnings from actual build output
 Banner('B U I L D - O U T P U T:')