Re: [Boost-build] [BBv2] Pre-compiled header (PCH) support

From: Reece Dunn (msclrhd_at_[hidden])
Date: 2005-11-20 14:03:33

Alex Besogonov wrote:
> Reece Dunn wrote:
>> This is a minor revision to correctly use :W where it is needed 
>> (including some places in the previous response file changeover).
> Thanks! Now I can _finally_ throw away all <cxxflags> hacks!

:)

> I've noticed a couple of minor problems:
> 1) In pch.jam:
> =================
> # Make mypch.hpp a pre-compiled header (PCH) using mypch.cpp as the 
> source file:
> #    pch mypch : mypch.cpp mypch.hpp ;
> =================
> But this won't work because hpp must be the first in the sources list 

I have now corrected this.

> (BTW, may be an order-independent syntax will be better?).

Yes. The question is how to do the filter inside the pch-generator *and* 
inside msvc.compile.pch.

> 2) PCH support won't work if precompiled header has ".h" extension and 
> not ".hpp".

Alexey has mentioned this to me off-list. The problem is that the H[PP] 
-> OBJ generators are intefering with the message compiler stuff. The 
solution is to have:

import cast ;

pch stdafx : [ cast _ pcheader : stdafx.h ] stdafx.cpp ;

exe microsoft
   :
     main.cpp demo.cpp stdafx
   ;

I have attached the updated that fixes these issues here.

- Reece


# Copyright (c) 2005 Reece H. Dunn.
#
# 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)

import type ;
import feature : feature ;
import generators ;

##### Using Pre-compiled Headers (Quick Guide) #####
#
# Make mypch.hpp a pre-compiled header (PCH) using mypch.cpp as the source file:
#    import cast ;
#    pch mypch : [ cast _ pcheader : pch.hpp ] pch.cpp ;
#
# Enable PCHs in a target:
#    exe hello : mypch main.cpp hello.cpp ;
#                ^^^^^ -- mypch.hpp is a PCH
#
# Don't use PCHs for a specific source:
#    obj nopch : nopch.cpp : <pch>off ;
#

type.register PCH : pch ;
type.register PCHEADER : pcheader ;

feature pch : # control precompiled header (PCH) generation
    on  # this file has support for using PCHs (if available)
    off # this file doesn't use PCHs
  ;

feature pch-source : : free dependency ; # mypch.cpp
feature pch-header : : free dependency ; # mypch.h[pp]
feature pch-file   : : free dependency ; # mypch.pch

class pch-generator : generator
{
    import property-set ;

    rule __init__ ( * : * )
    {
        generator.__init__ $(1) : $(2) : $(3) : $(4) : $(5) : $(6) : $(7) : $(8) : $(9) ;
    }

    rule action-class ( )
    {
        return compile-action ;
    }

    rule run ( project name ? : property-set : sources * )
    {
        local r =
          [ generator.run $(project) $(name) :
            [
              property-set.create
                <pch-source>$(sources[2]) # mypch.cpp
                [ $(property-set).raw ]
            ] : $(sources)
          ] ;

        return
          [ property-set.create
              <pch-header>$(sources[1]) # mypch.h[pp]
              <pch-file>$(r[2])         # mypch.pch
          ] $(r) ;
    }
}

Index: msvc.jam
===================================================================
RCS file: /cvsroot/boost/boost/tools/build/v2/tools/msvc.jam,v
retrieving revision 1.64
diff -u -r1.64 msvc.jam
--- msvc.jam	14 Nov 2005 15:15:06 -0000	1.64
+++ msvc.jam	20 Nov 2005 19:00:36 -0000
@@ -18,6 +18,7 @@
 import common ;
 import "class" : new ;
 import rc ;
+import pch ;
 
 if [ MATCH (--debug-configuration) : [ modules.peek : ARGV ] ]
 {
@@ -487,6 +488,8 @@
 generators.override msvc.compile.rc : rc.resource-compile ;
 generators.register-standard msvc.compile.asm : ASM : OBJ : <toolset>msvc ;
 
+generators.register [ new pch-generator msvc.compile.pch : PCHEADER : OBJ PCH : <toolset>msvc ] ;
+
 #
 # Declare flags and action for compilation
 #
@@ -537,15 +540,41 @@
 flags msvc.compile UNDEFS <undef> ;
 flags msvc.compile INCLUDES <include> ;
 
+flags msvc.compile PCH_SOURCE <pch-source> ;
+flags msvc.compile PCH_HEADER <pch>on : <pch-header> ;
+flags msvc.compile PCH_FILE <pch>on : <pch-file> ;
+
+rule compile.c ( targets + : sources * : properties * )
+{
+    DEPENDS $(<) : [ on $(<) return $(PCH_HEADER) ] ;
+    DEPENDS $(<) : [ on $(<) return $(PCH_FILE) ] ;
+}
+
+rule compile.c++ ( targets + : sources * : properties * )
+{
+    DEPENDS $(<) : [ on $(<) return $(PCH_HEADER) ] ;
+    DEPENDS $(<) : [ on $(<) return $(PCH_FILE) ] ;
+}
+
+rule compile.pch ( targets + : sources * : properties * )
+{
+    DEPENDS $(<) : [ on $(<) return $(PCH_SOURCE) ] ;
+}
+
 # The actions differ only by explicit selection of input language
-actions compile.c bind
+actions compile.c bind PCH_HEADER PCH_FILE
+{
+    $(.CC) /Zm800 -nologo -TC -U$(UNDEFS) $(CFLAGS) $(USER_CFLAGS) @"@($(<[1]:W).rsp:E=$(nl)"$(>:W)" $(nl)-D$(DEFINES) $(nl)"-I$(INCLUDES)")" -c -Fo"$(<[1]:W)" -Yu"$(PCH_HEADER:D=)" -Fp"$(PCH_FILE:W)"
+}
+
+actions compile.c++ bind PCH_HEADER PCH_FILE
 {
-    $(.CC) /Zm800 -nologo -TC -U$(UNDEFS) $(CFLAGS) $(USER_CFLAGS) @"@($(<[1]:W).rsp:E=$(nl)"$(>)" $(nl)-D$(DEFINES) $(nl)"-I$(INCLUDES)")" -c -Fo"$(<[1]:W)"
+    $(.CC) /Zm800 -nologo -TP -U$(UNDEFS) $(CFLAGS) $(C++FLAGS) $(USER_CFLAGS) @"@($(<[1]:W).rsp:E=$(nl)"$(>:W)" $(nl)-D$(DEFINES) $(nl)"-I$(INCLUDES)")" -c -Fo"$(<[1]:W)" -Yu"$(PCH_HEADER:D=)" -Fp"$(PCH_FILE:W)"
 }
 
-actions compile.c++ bind
+actions compile.pch bind PCH_SOURCE
 {
-    $(.CC) /Zm800 -nologo -TP -U$(UNDEFS) $(CFLAGS) $(C++FLAGS) $(USER_CFLAGS) @"@($(<[1]:W).rsp:E=$(nl)"$(>)" $(nl)-D$(DEFINES) $(nl)"-I$(INCLUDES)")" -c -Fo"$(<[1]:W)"
+    $(.CC) /Zm800 -nologo -TP -U$(UNDEFS) $(CFLAGS) $(C++FLAGS) $(USER_CFLAGS) @"@($(<[1]:W).rsp:E=$(nl)"$(PCH_SOURCE:W)" $(nl)-D$(DEFINES) $(nl)"-I$(INCLUDES)")" -c -Fo"$(<[1]:W)" /Yc"$(>[1]:D=)" -Fp"$(<[2]:W)"
 }
 
 actions compile.rc