[Boost-build] Boost.Jam problem with dependant includes

From: Fabien Chêne (fabien.chene_at_[hidden])
Date: 2006-09-27 19:28:42

Hi,

After a discussion on fr.comp.lang.c++ about Boost.[Build/Jam], James
Kanze pointed out that dependant macros do not cause dependencies.
According to §16.2.4, the following code is legal C++, and Boost.Jam
don't care about toto.hpp as a dependency :

cat toto.cpp
//------------------------------
#define DEPENDANT_INCLUDE( s ) #s
#include DEPENDANT_INCLUDE( toto.hpp )
//------------------------------

cat Jamfile
#-------------------------------
C++ = g++ ;
LINK = g++ ;
Library libtoto : toto.cpp ;
#-------------------------------
 
$ jam -dm -n 
make	--	all
time	--	all: unbound
make	--	 shell
time	--	 shell: unbound
make	--	  first
time	--	  first: unbound
made	stable	  first
made	stable	 shell
make	--	 files
time	--	 files: unbound
made	stable	 files
make	--	 lib
time	--	 lib: unbound
make	--	  libtoto.a
time	--	  libtoto.a: missing
make	--	   libtoto.a(toto.o)
time	--	   libtoto.a(toto.o): missing
make	--	    toto.o
time	--	    toto.o: missing
make	--	     toto.cpp
time	--	     toto.cpp: Mon Sep 25 01:10:05 2006
made*	newer	     toto.cpp
made+	missing	    toto.o
made+	update	   libtoto.a(toto.o)
made+	update	  libtoto.a
made	update	 lib
make	--	 exe
time	--	 exe: unbound
made	stable	 exe
make	--	 obj
time	--	 obj: unbound
made	update	 obj
made	update	all

I think the documentation is not clear enough about this problematic
limitation (the problem is the same with classic Jam).
Someone to confirm/infirm that ? If confirmed, is there a workaround ?
And i would find it more safe to block the build if an include is not
of the form of :

#include <h-char-sequence> new-line (§16.2.2)
#include "q-char-sequence" new-line (§16.2.3)

 

-- 
Fab