| # Copyright (c) 2005 Reece H. Dunn. |
| # Copyright 2006 Ilya Sokolov |
| # |
| # Use, modification and distribution is subject to the Boost Software |
| # License Version 1.0. (See accompanying file LICENSE_1_0.txt or |
| # http://www.boost.org/LICENSE_1_0.txt) |
| |
| ##### Using Precompiled Headers (Quick Guide) ##### |
| # |
| # Make precompiled mypch.hpp: |
| # |
| # import pch ; |
| # |
| # cpp-pch mypch |
| # : # sources |
| # mypch.hpp |
| # : # requiremnts |
| # <toolset>msvc:<source>mypch.cpp |
| # ; |
| # |
| # Add cpp-pch to sources: |
| # |
| # exe hello |
| # : main.cpp hello.cpp mypch |
| # ; |
| |
| import "class" : new ; |
| import type ; |
| import feature ; |
| import generators ; |
| |
| type.register PCH : pch ; |
| |
| type.register C_PCH : : PCH ; |
| type.register CPP_PCH : : PCH ; |
| |
| # Control precompiled header (PCH) generation. |
| feature.feature pch : |
| on |
| off |
| : propagated ; |
| |
| |
| feature.feature pch-header : : free dependency ; |
| feature.feature pch-file : : free dependency ; |
| |
| # Base PCH generator. The 'run' method has the logic to prevent this generator |
| # from being run unless it's being used for a top-level PCH target. |
| class pch-generator : generator |
| { |
| import property-set ; |
| |
| rule action-class ( ) |
| { |
| return compile-action ; |
| } |
| |
| rule run ( project name ? : property-set : sources + ) |
| { |
| if ! $(name) |
| { |
| # Unless this generator is invoked as the top-most generator for a |
| # main target, fail. This allows using 'H' type as input type for |
| # this generator, while preventing Boost.Build to try this generator |
| # when not explicitly asked for. |
| # |
| # One bad example is msvc, where pch generator produces both PCH |
| # target and OBJ target, so if there's any header generated (like by |
| # bison, or by msidl), we'd try to use pch generator to get OBJ from |
| # that H, which is completely wrong. By restricting this generator |
| # only to pch main target, such problem is solved. |
| } |
| else |
| { |
| local r = [ run-pch $(project) $(name) |
| : [ $(property-set).add-raw <define>BOOST_BUILD_PCH_ENABLED ] |
| : $(sources) ] ; |
| return [ generators.add-usage-requirements $(r) |
| : <define>BOOST_BUILD_PCH_ENABLED ] ; |
| } |
| } |
| |
| # This rule must be overridden by the derived classes. |
| rule run-pch ( project name ? : property-set : sources + ) |
| { |
| } |
| } |
| |
| |
| # NOTE: requirements are empty, default pch generator can be applied when |
| # pch=off. |
| generators.register |
| [ new dummy-generator pch.default-c-pch-generator : : C_PCH ] ; |
| generators.register |
| [ new dummy-generator pch.default-cpp-pch-generator : : CPP_PCH ] ; |