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@larroy /
Created Oct 28, 2011

Precompiled header builder for SCons
# SCons builder for gcc's precompiled headers
# Copyright (C) 2006 Tim Blechmann (C) 2011 Pedro Larroy
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with this program; see the file COPYING. If not, write to
# the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA.
# 1.2
# 09-11-2011 Pedro Larroy: Fixed dependency emitter not working with variant dir
# 07-09-2012 Pedro Larroy: Create the resulting pch on the variant directory,
# the variant dir should be added to the includes, before any of the other
# local includes for the compiler to search the pch file on the build directory
# that we just created. In doubt execute 'strace -f g++ ...' to check that it
# opens the correct pch.
# FIXME: the original precompiled header has to be set
# in the environment as
# env['precompiled_header'], this should be fixed
# Example usage:
# src_variant_dir = 'build/release'
# includes = [
# Dir(src_variant_dir),
# ... other includes ...
# ]
# ... set includes in environment ...
# env['precompiled_header'] = File('src/common/includes/all.h')
# env['Gch'] = env.Gch(target='common/includes/all.h.gch', source=env['precompiled_header'])
import SCons.Action
import SCons.Builder
import SCons.Scanner.C
import SCons.Util
import SCons.Script
import os
import functools
GchAction = SCons.Action.Action('$GCHCOM', '$GCHCOMSTR')
GchShAction = SCons.Action.Action('$GCHSHCOM', '$GCHSHCOMSTR')
def gen_suffix(env, sources):
return sources[0].get_suffix() + env['GCHSUFFIX']
GchShBuilder = SCons.Builder.Builder(action = GchShAction,
source_scanner = SCons.Scanner.C.CScanner(),
suffix = gen_suffix)
GchBuilder = SCons.Builder.Builder(action = GchAction,
source_scanner = SCons.Scanner.C.CScanner(),
suffix = gen_suffix)
def header_path(node):
h_path = node.abspath
idx = h_path.rfind('.gch')
if idx != -1:
h_path = h_path[0:idx]
if not os.path.isfile(h_path):
raise SCons.Errors.StopError("can't find header file: {0}".format(h_path))
return h_path
raise SCons.Errors.StopError("{0} file doesn't have .gch extension".format(h_path))
def pch_emitter(pch_env_key, target, source, env):
# print 'target', target[0].str_for_display(), 'source', str(source[0])
# print 'target'
# print map(lambda x: x.str_for_display(), target)
# print 'source'
# print map(lambda x: x.str_for_display(), source)
# print 'env:'
# print env.get(pch_env_key)
# print type(env.get(pch_env_key))
# print
SCons.Defaults.StaticObjectEmitter( target, source, env )
scanner = SCons.Scanner.C.CScanner()
path = scanner.path(env)
deps = scanner(source[0], env, path)
if env.get(pch_env_key):
h_path = env['precompiled_header'].abspath
#print 'h_path', h_path
#print env['Gch'].abspath
#print map(lambda x: x.str_for_display(), deps)
#if h_path in [x.abspath for x in deps]:
for i in [x.abspath for x in deps]:
#print '|{0}|{1}|'.format(i, h_path)
if i == h_path:
if 'explain' in env.GetOption('debug'):
print 'Found dep. on pch: ', source[0], ' -> ', env[pch_env_key]
env.Depends(target, env[pch_env_key])
return (target, source)
def generate(env):
Add builders and construction variables for the Gch builder.
env.Append(BUILDERS = {
'gch': env.Builder(
action = GchAction,
suffix = 'gch',
target_factory = env.fs.File,
'gchsh': env.Builder(
action = GchShAction,
target_factory = env.fs.File,
bld = env['BUILDERS']['Gch']
bldsh = env['BUILDERS']['GchSh']
except KeyError:
bld = GchBuilder
bldsh = GchShBuilder
env['BUILDERS']['Gch'] = bld
env['BUILDERS']['GchSh'] = bldsh
env['GCHCOM'] = '$CXX -Wall -o $TARGET -x c++-header -c $CXXFLAGS $CCFLAGS $_CCCOMCOM $SOURCE'
env['GCHSUFFIX'] = '.gch'
for suffix in SCons.Util.Split('.c .C .cc .cxx .cpp .c++'):
static_pch_emitter = functools.partial(pch_emitter, 'Gch')
env['BUILDERS']['StaticObject'].add_emitter( suffix, static_pch_emitter )
shared_pch_emitter = functools.partial(pch_emitter, 'GchSh')
env['BUILDERS']['SharedObject'].add_emitter( suffix, shared_pch_emitter )
def exists(env):
return env.Detect('g++')
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