third_party/waf/waflib/extras/pch.py

   1 #! /usr/bin/env python
   2 # encoding: utf-8
   3 # WARNING! Do not edit! https://waf.io/book/index.html#_obtaining_the_waf_file
   4
   5 #! /usr/bin/env python
   6 # encoding: utf-8
   7 # Alexander Afanasyev (UCLA), 2014
   8
   9 """
  10 Enable precompiled C++ header support (currently only clang++ and g++ are supported)
  11
  12 To use this tool, wscript should look like:
  13
  14         def options(opt):
  15                 opt.load('pch')
  16                 # This will add `--with-pch` configure option.
  17                 # Unless --with-pch during configure stage specified, the precompiled header support is disabled
  18
  19         def configure(conf):
  20                 conf.load('pch')
  21                 # this will set conf.env.WITH_PCH if --with-pch is specified and the supported compiler is used
  22                 # Unless conf.env.WITH_PCH is set, the precompiled header support is disabled
  23
  24         def build(bld):
  25                 bld(features='cxx pch',
  26                         target='precompiled-headers',
  27                         name='precompiled-headers',
  28                         headers='a.h b.h c.h', # headers to pre-compile into `precompiled-headers`
  29
  30                         # Other parameters to compile precompiled headers
  31                         # includes=...,
  32                         # export_includes=...,
  33                         # use=...,
  34                         # ...
  35
  36                         # Exported parameters will be propagated even if precompiled headers are disabled
  37                 )
  38
  39                 bld(
  40                         target='test',
  41                         features='cxx cxxprogram',
  42                         source='a.cpp b.cpp d.cpp main.cpp',
  43                         use='precompiled-headers',
  44                 )
  45
  46                 # or
  47
  48                 bld(
  49                         target='test',
  50                         features='pch cxx cxxprogram',
  51                         source='a.cpp b.cpp d.cpp main.cpp',
  52                         headers='a.h b.h c.h',
  53                 )
  54
  55 Note that precompiled header must have multiple inclusion guards.  If the guards are missing, any benefit of precompiled header will be voided and compilation may fail in some cases.
  56 """
  57
  58 import os
  59 from waflib import Task, TaskGen, Utils
  60 from waflib.Tools import c_preproc, cxx
  61
  62
  63 PCH_COMPILER_OPTIONS = {
  64         'clang++': [['-include'], '.pch', ['-x', 'c++-header']],
  65         'g++':     [['-include'], '.gch', ['-x', 'c++-header']],
  66 }
  67
  68
  69 def options(opt):
  70         opt.add_option('--without-pch', action='store_false', default=True, dest='with_pch', help='''Try to use precompiled header to speed up compilation (only g++ and clang++)''')
  71
  72 def configure(conf):
  73         if (conf.options.with_pch and conf.env['COMPILER_CXX'] in PCH_COMPILER_OPTIONS.keys()):
  74                 conf.env.WITH_PCH = True
  75                 flags = PCH_COMPILER_OPTIONS[conf.env['COMPILER_CXX']]
  76                 conf.env.CXXPCH_F = flags[0]
  77                 conf.env.CXXPCH_EXT = flags[1]
  78                 conf.env.CXXPCH_FLAGS = flags[2]
  79
  80
  81 @TaskGen.feature('pch')
  82 @TaskGen.before('process_source')
  83 def apply_pch(self):
  84         if not self.env.WITH_PCH:
  85                 return
  86
  87         if getattr(self.bld, 'pch_tasks', None) is None:
  88                 self.bld.pch_tasks = {}
  89
  90         if getattr(self, 'headers', None) is None:
  91                 return
  92
  93         self.headers = self.to_nodes(self.headers)
  94
  95         if getattr(self, 'name', None):
  96                 try:
  97                         task = self.bld.pch_tasks[self.name]
  98                         self.bld.fatal("Duplicated 'pch' task with name %r" % self.name)
  99                 except KeyError:
 100                         pass
 101
 102         out = '%s.%d%s' % (self.target, self.idx, self.env['CXXPCH_EXT'])
 103         out = self.path.find_or_declare(out)
 104         task = self.create_task('gchx', self.headers, out)
 105
 106         # target should be an absolute path of `out`, but without precompiled header extension
 107         task.target = out.abspath()[:-len(out.suffix())]
 108
 109         self.pch_task = task
 110         if getattr(self, 'name', None):
 111                 self.bld.pch_tasks[self.name] = task
 112
 113 @TaskGen.feature('cxx')
 114 @TaskGen.after_method('process_source', 'propagate_uselib_vars')
 115 def add_pch(self):
 116         if not (self.env['WITH_PCH'] and getattr(self, 'use', None) and getattr(self, 'compiled_tasks', None) and getattr(self.bld, 'pch_tasks', None)):
 117                 return
 118
 119         pch = None
 120         # find pch task, if any
 121
 122         if getattr(self, 'pch_task', None):
 123                 pch = self.pch_task
 124         else:
 125                 for use in Utils.to_list(self.use):
 126                         try:
 127                                 pch = self.bld.pch_tasks[use]
 128                         except KeyError:
 129                                 pass
 130
 131         if pch:
 132                 for x in self.compiled_tasks:
 133                         x.env.append_value('CXXFLAGS', self.env['CXXPCH_F'] + [pch.target])
 134
 135 class gchx(Task.Task):
 136         run_str = '${CXX} ${ARCH_ST:ARCH} ${CXXFLAGS} ${CXXPCH_FLAGS} ${FRAMEWORKPATH_ST:FRAMEWORKPATH} ${CPPPATH_ST:INCPATHS} ${DEFINES_ST:DEFINES} ${CXXPCH_F:SRC} ${CXX_SRC_F}${SRC[0].abspath()} ${CXX_TGT_F}${TGT[0].abspath()} ${CPPFLAGS}'
 137         scan    = c_preproc.scan
 138         color   = 'BLUE'
 139         ext_out=['.h']
 140
 141         def runnable_status(self):
 142                 try:
 143                         node_deps = self.generator.bld.node_deps[self.uid()]
 144                 except KeyError:
 145                         node_deps = []
 146                 ret = Task.Task.runnable_status(self)
 147                 if ret == Task.SKIP_ME and self.env.CXX_NAME == 'clang':
 148                         t = os.stat(self.outputs[0].abspath()).st_mtime
 149                         for n in self.inputs + node_deps:
 150                                 if os.stat(n.abspath()).st_mtime > t:
 151                                         return Task.RUN_ME
 152                 return ret