PATCH: Install four PCH files instead of one

[Loren James Rittle <rittle at latour dot rsch dot comm dot mot dot com>]

Benjamin, this patch replaces a piece of the first patch you posted to
enable PCH.  Sorry, I just noticed that you made changes (because you
had to) when you made it respect configure-time checks in the second
version.

Although, I'm afraid of installing ~50MB of PCH files, I think
creating ~four PCH files is better than just one.  This set will cover
most user options provided (and indeed all situations I found while
first working with the PCH stuff, running make check from top-level
vs. within libstdc++-v3, rebuilding from top-level vs. within
libstdc++-v3): -O0, -O2, "-O0 -g", "-O2 -g".

Also, note, please don't touch something in ${glibcpp_srcdir}.
The whole reason for a stamp file should remove any need to touch it.

(I'll update it and commit it once I see yours go in and you say you
agree; or else free feel to include it in your before you first commit.)

Regards,
Loren

Index: libstdc++-v3/include/Makefile.am
===================================================================
RCS file: /cvs/gcc/gcc/libstdc++-v3/include/Makefile.am,v
retrieving revision 1.54
diff -c -r1.54 Makefile.am
*** libstdc++-v3/include/Makefile.am	14 Mar 2003 22:16:05 -0000	1.54
--- libstdc++-v3/include/Makefile.am	16 Apr 2003 23:11:13 -0000
***************
*** 341,354 ****
  	${target_builddir}/gthr-default.h
  
  pch_input = stdc++.h
! pch_output = stdc++.h.gch
  pch_source = ${glibcpp_srcdir}/include/${pch_input}
  
  # List of all timestamp files.  By keeping only one copy of this list, both
  # CLEANFILES and all-local are kept up-to-date.
  allstamps = \
  	stamp-std stamp-bits stamp-c_base stamp-c_compatibility \
! 	stamp-backward stamp-ext stamp-target
  
  # Here are the rules for building the headers
  all-local: ${target_builddir}/c++config.h ${thread_target_headers} ${allstamps}
--- 341,354 ----
  	${target_builddir}/gthr-default.h
  
  pch_input = stdc++.h
! pch_output_builddir = stdc++.h.gch
  pch_source = ${glibcpp_srcdir}/include/${pch_input}
  
  # List of all timestamp files.  By keeping only one copy of this list, both
  # CLEANFILES and all-local are kept up-to-date.
  allstamps = \
  	stamp-std stamp-bits stamp-c_base stamp-c_compatibility \
! 	stamp-backward stamp-ext stamp-target stamp-stdc++-precompile
  
  # Here are the rules for building the headers
  all-local: ${target_builddir}/c++config.h ${thread_target_headers} ${allstamps}
***************
*** 367,378 ****
  	  echo `date` > stamp-std ;\
  	fi
  
! PCHFLAGS=-Winvalid-pch -x c++-header $(CXXFLAGS)
  stamp-stdc++-precompile: stamp-std ${target_builddir}/c++config.h ${pch_source}
! 	if [ ! -f "${pch_output}" ]; then \
! 	  $(CXX) $(PCHFLAGS) $(INCLUDES) ${pch_source} -o ${pch_output}; \
! 	  touch ${pch_input}; \
  	fi; \
  	touch stamp-stdc++-precompile
  
  stamp-bits: ${bits_headers}
--- 367,381 ----
  	  echo `date` > stamp-std ;\
  	fi
  
! PCHFLAGS=-Winvalid-pch -Wno-deprecated -x c++-header $(CXXFLAGS)
  stamp-stdc++-precompile: stamp-std ${target_builddir}/c++config.h ${pch_source}
! 	if [ ! -d "${pch_output_builddir}" ]; then \
! 	  mkdir -p ${pch_output_builddir}; \
  	fi; \
+ 	$(CXX) $(PCHFLAGS) $(INCLUDES) ${pch_source} -O0 -o ${pch_output_builddir}/O0; \
+ 	$(CXX) $(PCHFLAGS) $(INCLUDES) ${pch_source} -O2 -o ${pch_output_builddir}/O2; \
+ 	$(CXX) $(PCHFLAGS) $(INCLUDES) ${pch_source} -O0 -g -o ${pch_output_builddir}/O0g; \
+ 	$(CXX) $(PCHFLAGS) $(INCLUDES) ${pch_source} -O2 -g -o ${pch_output_builddir}/O2g; \
  	touch stamp-stdc++-precompile
  
  stamp-bits: ${bits_headers}
***************
*** 388,398 ****
  	@if [ ! -d "${c_base_builddir}" ]; then \
  	  mkdir -p ${c_base_builddir} ;\
  	fi ;\
- 	(cd ${c_base_builddir} && for h in ${c_base_headers}; do \
- 	  official_name=`echo $$h | sed -e 's,.*/std_,,' -e 's,\.h$$,,'` ;\
- 	  @LN_S@ $$h ./$${official_name} || true ;\
- 	done) ;\
  	if [ ! -f stamp-c_base ]; then \
  	  if [ ! -z "${c_base_headers_extra}" ]; then \
  	  (cd ${bits_builddir} && @LN_S@ ${c_base_headers_extra}  . || true) ;\
  	  fi ;\
--- 391,401 ----
  	@if [ ! -d "${c_base_builddir}" ]; then \
  	  mkdir -p ${c_base_builddir} ;\
  	fi ;\
  	if [ ! -f stamp-c_base ]; then \
+ 	  (cd ${c_base_builddir} && for h in ${c_base_headers}; do \
+ 	    official_name=`echo $$h | sed -e 's,.*/std_,,' -e 's,\.h$$,,'` ;\
+ 	    @LN_S@ $$h ./$${official_name} || true ;\
+ 	  done) ;\
  	  if [ ! -z "${c_base_headers_extra}" ]; then \
  	  (cd ${bits_builddir} && @LN_S@ ${c_base_headers_extra}  . || true) ;\
  	  fi ;\
***************
*** 524,529 ****
--- 527,535 ----
  	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${std_builddir}
  	for file in ${std_headers_rename}; do \
  	  $(INSTALL_DATA) ${std_builddir}/$${file} $(DESTDIR)${gxx_include_dir}/${std_builddir}; done
+ 	$(INSTALL_DATA) ${std_builddir}/${pch_input} $(DESTDIR)${gxx_include_dir}/${std_builddir}
+ 	for file in ${std_builddir}/${pch_output_builddir}/*; do \
+ 	  $(INSTALL_DATA) $$file $(DESTDIR)${gxx_include_dir}/${std_builddir}/${pch_output_builddir}; done
  	$(mkinstalldirs) $(DESTDIR)${gxx_include_dir}/${target_builddir}
  	for file in ${target_headers} ${target_headers_extra} \
  	 ${thread_target_headers}; do \