configure.ac: Add --enable-build-with-cxx.

./:	* configure.ac: Add --enable-build-with-cxx.  When set, add c++ to
	boot_languages.  Only bootstrap target libraries listed in
	target_libs for some boot language.  Add --with-stage1-ldflags,
	--with-stage1-libs, --with-boot-ldflags, --with-boot-libs.  Remove
	with_host_libstdcxx from ppllibs.  Only add -fkeep-inline-functions
	if not building with C++.
	* Makefile.def: For target_module libstdc++-v3, set bootstrap=true.
	* Makefile.tpl (STAGE1_LDFLAGS, STAGE1_LIBS): New variables.
	(POSTSTAGE1_LDFLAGS, POSTSTAGE1_LIBS): New variables.
	(HOST_EXPORTS): Add STAGE1_LDFLAGS to LDFLAGS.  Export HOST_LIBS.
	(POSTSTAGE1_HOST_EXPORTS): Set CXX and CXX_FOR_BUILD.  Add
	POSTSTAGE1_LDFLAGS to LDFLAGS.  Export HOST_LIBS.
	(POSTSTAGE1_FLAGS_TO_PASS): Likewise.
	* configure, Makefile.in: Rebuild.
gcc/:
	* configure.ac: Invoke AC_PROG_CXX.  Separate C specific warnings
	from loose_warn into c_loose_warn and from strict_warn into
	c_strict_warn.  Set and substitute warn_cxxflags.  Check for
	--enable-build-with-cxx.  Set and substitute
	ENABLE_BUILD_WITH_CXX.  Set and substitute HOST_LIBS.
	* Makefile.in (CXXFLAGS): New variable.
	(C_LOOSE_WARN, C_STRICT_WARN): New variables.
	(GCC_WARN_CFLAGS): Add $(C_LOOSE_WARN).  Add $(C_STRICT_WARN) if
	the default is the same as $(STRICT_WARN).
	(GCC_WARN_CXXFLAGS, WARN_CXXFLAGS): New variables.
	(CXX): New variable.
	(COMPILER): New value if ENABLE_BUILD_WITH_CXX.
	(COMPILER_FLAGS, LINKER, LINKER_FLAGS): Likewise.
	(ALL_COMPILERFLAGS, ALL_LINKERFLAGS): Likewise.
	(HOST_LIBS): New variable.
	(GCC_CFLAGS): Add $(C_LOOSE_WARN).
	(ALL_CXXFLAGS): New variable.
	(LIBS, BACKENDLIBS): Add $(HOST_LIBS).
	* doc/install.texi (Configuration): Document
	--enable-build-with-cxx, --with-stage1-ldflags,
	--with-stage1-libs, --with-boot-ldflags, --with-boot-libs.
	* configure: Rebuild.

From-SVN: r148889

ChangeLog

+2009-06-23  Ian Lance Taylor  <iant@google.com>
+
+	* configure.ac: Add --enable-build-with-cxx.  When set, add c++ to
+	boot_languages.  Only bootstrap target libraries listed in
+	target_libs for some boot language.  Add --with-stage1-ldflags,
+	--with-stage1-libs, --with-boot-ldflags, --with-boot-libs.  Remove
+	with_host_libstdcxx from ppllibs.  Only add -fkeep-inline-functions
+	if not building with C++.
+	* Makefile.def: For target_module libstdc++-v3, set bootstrap=true.
+	* Makefile.tpl (STAGE1_LDFLAGS, STAGE1_LIBS): New variables.
+	(POSTSTAGE1_LDFLAGS, POSTSTAGE1_LIBS): New variables.
+	(HOST_EXPORTS): Add STAGE1_LDFLAGS to LDFLAGS.  Export HOST_LIBS.
+	(POSTSTAGE1_HOST_EXPORTS): Set CXX and CXX_FOR_BUILD.  Add
+	POSTSTAGE1_LDFLAGS to LDFLAGS.  Export HOST_LIBS.
+	(POSTSTAGE1_FLAGS_TO_PASS): Likewise.
+	* configure, Makefile.in: Rebuild.
+
 2009-06-23  Li Feng  <nemokingdom@gmail.com>
 
 	* MAINTAINERS: Added my name to write-after-approval list.

Makefile.def

@@ -141,7 +141,10 @@ host_modules= { module= libtermcap; no_check=true;
 host_modules= { module= utils; no_check=true; };
 host_modules= { module= gnattools; };
 
-target_modules = { module= libstdc++-v3; lib_path=.libs; raw_cxx=true; };
+target_modules = { module= libstdc++-v3;
+		   bootstrap=true;
+		   lib_path=.libs;
+		   raw_cxx=true; };
 target_modules = { module= libmudflap; lib_path=.libs; };
 target_modules = { module= libssp; lib_path=.libs; };
 target_modules = { module= newlib; };

Makefile.tpl

@@ -120,6 +120,19 @@ BUILD_SUBDIR = @build_subdir@
 # directories built for the build system.
 BUILD_CONFIGARGS = @build_configargs@ --with-build-subdir="$(BUILD_SUBDIR)"
 
+# Linker flags to use on the host, for stage1 or when not
+# bootstrapping.
+STAGE1_LDFLAGS = @stage1_ldflags@
+
+# Libraries to use on the host, for stage1 or when not bootstrapping.
+STAGE1_LIBS = @stage1_libs@
+
+# Linker flags to use for stage2 and later.
+POSTSTAGE1_LDFLAGS = @poststage1_ldflags@
+
+# Libraries to use for stage2 and later.
+POSTSTAGE1_LIBS = @poststage1_libs@
+
 # This is the list of variables to export in the environment when
 # configuring any subdirectory.  It must also be exported whenever
 # recursing into a build directory in case that directory's Makefile
@@ -185,7 +198,7 @@ HOST_EXPORTS = \
 	CC_FOR_BUILD="$(CC_FOR_BUILD)"; export CC_FOR_BUILD; \
 	DLLTOOL="$(DLLTOOL)"; export DLLTOOL; \
 	LD="$(LD)"; export LD; \
-	LDFLAGS="$(LDFLAGS)"; export LDFLAGS; \
+	LDFLAGS="$(STAGE1_LDFLAGS) $(LDFLAGS)"; export LDFLAGS; \
 	NM="$(NM)"; export NM; \
 	RANLIB="$(RANLIB)"; export RANLIB; \
 	WINDRES="$(WINDRES)"; export WINDRES; \
@@ -200,6 +213,7 @@ HOST_EXPORTS = \
 	OBJDUMP_FOR_TARGET="$(OBJDUMP_FOR_TARGET)"; export OBJDUMP_FOR_TARGET; \
 	RANLIB_FOR_TARGET="$(RANLIB_FOR_TARGET)"; export RANLIB_FOR_TARGET; \
 	TOPLEVEL_CONFIGURE_ARGUMENTS="$(TOPLEVEL_CONFIGURE_ARGUMENTS)"; export TOPLEVEL_CONFIGURE_ARGUMENTS; \
+	HOST_LIBS="$(STAGE1_LIBS)"; export HOST_LIBS; \
 	GMPLIBS="$(HOST_GMPLIBS)"; export GMPLIBS; \
 	GMPINC="$(HOST_GMPINC)"; export GMPINC; \
 	PPLLIBS="$(HOST_PPLLIBS)"; export PPLLIBS; \
@@ -218,8 +232,16 @@ POSTSTAGE1_HOST_EXPORTS = \
 	  -B$$r/$(HOST_SUBDIR)/prev-gcc/ -B$(build_tooldir)/bin/ \
 	  $(XGCC_FLAGS_FOR_TARGET) $$TFLAGS"; export CC; \
 	CC_FOR_BUILD="$$CC"; export CC_FOR_BUILD; \
-	GNATBIND="$$r/$(HOST_SUBDIR)/prev-gcc/gnatbind"; export GNATBIND \
-	LDFLAGS="$(BOOT_LDFLAGS)"; export LDFLAGS;
+	CXX="$(STAGE_CC_WRAPPER) $$r/$(HOST_SUBDIR)/prev-gcc/g++$(exeext) \
+	  -B$$r/$(HOST_SUBDIR)/prev-gcc/ -B$(build_tooldir)/bin/ -nostdinc++ \
+	  -I$$r/prev-$(TARGET_SUBDIR)/libstdc++-v3/include/$(TARGET_SUBDIR) \
+	  -I$$r/prev-$(TARGET_SUBDIR)/libstdc++-v3/include \
+	  -I$$r/$(srcdir)/libstdc++-v3/libsupc++ \
+	  -L$$r/prev-$(TARGET_SUBDIR)/libstdc++-v3/src/.libs"; export CXX; \
+	CXX_FOR_BUILD="$$CXX"; export CXX_FOR_BUILD; \
+	GNATBIND="$$r/$(HOST_SUBDIR)/prev-gcc/gnatbind"; export GNATBIND; \
+	LDFLAGS="$(POSTSTAGE1_LDFLAGS) $(BOOT_LDFLAGS)"; export LDFLAGS; \
+	HOST_LIBS="$(POSTSTAGE1_LIBS)"; export HOST_LIBS;
 
 # Target libraries are put under this directory:
 TARGET_SUBDIR = @target_subdir@
@@ -540,8 +562,11 @@ X11_FLAGS_TO_PASS = \
 # Flags to pass to stage2 and later makes.
 
 POSTSTAGE1_FLAGS_TO_PASS = \
-	CC="$${CC}" CC_FOR_BUILD="$${CC_FOR_BUILD}" GNATBIND="$${GNATBIND}" \
-	LDFLAGS="$(BOOT_LDFLAGS)" \
+	CC="$${CC}" CC_FOR_BUILD="$${CC_FOR_BUILD}" \
+	CXX="$${CXX}" CXX_FOR_BUILD="$${CXX_FOR_BUILD}" \
+	GNATBIND="$${GNATBIND}" \
+	LDFLAGS="$(POSTSTAGE1_LDFLAGS) $(BOOT_LDFLAGS)" \
+	HOST_LIBS="$(POSTSTAGE1_LIBS)" \
 	"`echo 'ADAFLAGS=$(BOOT_ADAFLAGS)' | sed -e s'/[^=][^=]*=$$/XFOO=/'`"
 
 # Flags to pass down to makes which are built with the target environment.

configure.ac

@@ -1191,6 +1191,12 @@ fi
 ACX_PROG_GNAT
 ACX_PROG_CMP_IGNORE_INITIAL
 
+# See if we are building gcc with C++.
+AC_ARG_ENABLE(build-with-cxx,
+[  --enable-build-with-cxx build with C++ compiler instead of C compiler],
+ENABLE_BUILD_WITH_CXX=$enableval,
+ENABLE_BUILD_WITH_CXX=no)
+
 # Check for GMP, MPFR and MPC
 gmplibs="-lmpfr -lgmp"
 gmpinc=
@@ -1422,10 +1428,59 @@ case $with_host_libstdcxx in
     ;;
 esac
 
+# Linker flags to use for stage1 or when not boostrapping.
+AC_ARG_WITH(stage1-ldflags,
+[  --with-stage1-ldflags=FLAGS Linker flags for stage1],
+[if test "$withval" = "no" -o "$withval" = "yes"; then
+   stage1_ldflags=
+ else
+   stage1_ldflags=$withval
+ fi],
+[stage1_ldflags=])
+AC_SUBST(stage1_ldflags)
+
+# Libraries to use for stage1 or when not bootstrapping.
+AC_ARG_WITH(stage1-libs,
+[  -with-stage1-libs=LIBS      Libraries for stage1],
+[if test "$withval" = "no" -o "$withval" = "yes"; then
+   stage1_libs=
+ else
+   stage1_libs=$withval
+ fi],
+[stage1_libs=$with_host_libstdcxx])
+AC_SUBST(stage1_libs)
+
+# Linker flags to use for stage2 and later builds.
+AC_ARG_WITH(boot-ldflags,
+[  --with-boot-ldflags=FLAGS Linker flags for stage2 and later],
+[if test "$withval" = "no" -o "$withval" = "yes"; then
+   poststage1_ldflags=
+ else
+   poststage1_ldflags=$withval
+ fi],
+[if test "$ENABLE_BUILD_WITH_CXX" = "yes"; then
+   poststage1_ldflags=-static-libstdc++
+ else
+   poststage1_ldflags=
+ fi])
+AC_SUBST(poststage1_ldflags)
+
+# Libraries to use for stage2 and later builds.  This defaults to the
+# argument passed to --with-host-libstdcxx.
+AC_ARG_WITH(boot-libs,
+[  --with-boot-libs=LIBS     Libraries for stage2 and later]
+[if test "$withval" = "no" -o "$withval" = "yes"; then
+   poststage1_libs=
+ else
+  poststage1_libs=$withval
+ fi],
+[poststage1_libs=$with_host_libstdcxx])
+AC_SUBST(poststage1_libs)
+
 # Check for PPL
 ppl_major_version=0
 ppl_minor_version=10
-ppllibs=" -lppl_c -lppl -lgmpxx $with_host_libstdcxx "
+ppllibs=" -lppl_c -lppl -lgmpxx"
 pplinc=
 
 AC_ARG_WITH(ppl, [  --with-ppl=PATH         Specify prefix directory for the installed PPL package
@@ -1439,7 +1494,7 @@ case $with_ppl in
     ppllibs=
     ;;
   *)
-    ppllibs="-L$with_ppl/lib -lppl_c -lppl -lgmpxx $with_host_libstdcxx"
+    ppllibs="-L$with_ppl/lib -lppl_c -lppl -lgmpxx"
     pplinc="-I$with_ppl/include $pplinc"
     LIBS="$ppllibs $LIBS"
     ;;
@@ -1448,11 +1503,11 @@ if test "x$with_ppl_include" != x; then
   pplinc="-I$with_ppl_include $pplinc"
 fi
 if test "x$with_ppl_lib" != x; then
-  ppllibs="-L$with_ppl_lib -lppl_c -lppl -lgmpxx $with_host_libstdcxx"
+  ppllibs="-L$with_ppl_lib -lppl_c -lppl -lgmpxx"
   LIBS="$ppllibs $LIBS"
 fi
 if test "x$with_ppl$with_ppl_include$with_ppl_lib" = x && test -d ${srcdir}/ppl; then
-  ppllibs='-L$$r/$(HOST_SUBDIR)/ppl/.libs -L$$r/$(HOST_SUBDIR)/ppl/_libs -lppl_c -lppl -lgmpxx '"$with_host_libstdcxx "
+  ppllibs='-L$$r/$(HOST_SUBDIR)/ppl/.libs -L$$r/$(HOST_SUBDIR)/ppl/_libs -lppl_c -lppl -lgmpxx '
   pplinc='-I$$r/$(HOST_SUBDIR)/ppl/include -I$$s/ppl/include '
   LIBS="$ppllibs $LIBS"
 fi
@@ -1538,6 +1593,9 @@ AC_SUBST(clooginc)
 # By default, C is the only stage 1 language.
 stage1_languages=,c,
 
+# Target libraries that we bootstrap.
+bootstrap_target_libs=,target-libgcc,
+
 # Figure out what language subdirectories are present.
 # Look if the user specified --enable-languages="..."; if not, use
 # the environment variable $LANGUAGES if defined. $LANGUAGES might
@@ -1623,6 +1681,10 @@ if test -d ${srcdir}/gcc; then
           exit 1
         fi
 
+	if test "$language" = "c++" -a "$ENABLE_BUILD_WITH_CXX" = "yes"; then
+	  boot_language=yes
+	fi
+
         case ,${enable_languages}, in
           *,${language},*)
             # Language was explicitly selected; include it.
@@ -1689,6 +1751,8 @@ if test -d ${srcdir}/gcc; then
 	      yes)
 		# Add to (comma-separated) list of stage 1 languages.
 		stage1_languages="${stage1_languages}${language},"
+		# We need to bootstrap any supporting libraries.
+		bootstrap_target_libs="${bootstrap_target_libs}${target_libs},"
 		;;
 	    esac
 	    ;;
@@ -2420,11 +2484,18 @@ for module in ${target_configdirs} ; do
     echo 1>&2 "*** removing ${target_subdir}/${module}/Makefile to force reconfigure"
     rm -f ${target_subdir}/${module}/Makefile
   fi
+
+  # We only bootstrap target libraries listed in bootstrap_target_libs.
+  case $bootstrap_target_libs in
+    *,target-$module,*) target_bootstrap_suffix=$bootstrap_suffix ;;
+    *) target_bootstrap_suffix=no-bootstrap ;;
+  esac
+
   extrasub="$extrasub
 /^@if target-$module\$/d
 /^@endif target-$module\$/d
-/^@if target-$module-$bootstrap_suffix\$/d
-/^@endif target-$module-$bootstrap_suffix\$/d"
+/^@if target-$module-$target_bootstrap_suffix\$/d
+/^@endif target-$module-$target_bootstrap_suffix\$/d"
 done
 
 extrasub="$extrasub
@@ -2988,7 +3059,7 @@ case $build in
 esac
 
 # This is aimed to mimic bootstrap with a non-GCC compiler to catch problems.
-if test "$GCC" = yes; then
+if test "$GCC" = yes -a "$ENABLE_BUILD_WITH_CXX" != yes; then
   saved_CFLAGS="$CFLAGS"
 
   # Pass -fkeep-inline-functions for stage 1 if the GCC version supports it.

gcc/ChangeLog

+2009-06-23  Ian Lance Taylor  <iant@google.com>
+
+	* configure.ac: Invoke AC_PROG_CXX.  Separate C specific warnings
+	from loose_warn into c_loose_warn and from strict_warn into
+	c_strict_warn.  Set and substitute warn_cxxflags.  Check for
+	--enable-build-with-cxx.  Set and substitute
+	ENABLE_BUILD_WITH_CXX.  Set and substitute HOST_LIBS.
+	* Makefile.in (CXXFLAGS): New variable.
+	(C_LOOSE_WARN, C_STRICT_WARN): New variables.
+	(GCC_WARN_CFLAGS): Add $(C_LOOSE_WARN).  Add $(C_STRICT_WARN) if
+	the default is the same as $(STRICT_WARN).
+	(GCC_WARN_CXXFLAGS, WARN_CXXFLAGS): New variables.
+	(CXX): New variable.
+	(COMPILER): New value if ENABLE_BUILD_WITH_CXX.
+	(COMPILER_FLAGS, LINKER, LINKER_FLAGS): Likewise.
+	(ALL_COMPILERFLAGS, ALL_LINKERFLAGS): Likewise.
+	(HOST_LIBS): New variable.
+	(GCC_CFLAGS): Add $(C_LOOSE_WARN).
+	(ALL_CXXFLAGS): New variable.
+	(LIBS, BACKENDLIBS): Add $(HOST_LIBS).
+	* doc/install.texi (Configuration): Document
+	--enable-build-with-cxx, --with-stage1-ldflags,
+	--with-stage1-libs, --with-boot-ldflags, --with-boot-libs.
+	* configure: Rebuild.
+
 2009-06-24  Ramana Radhakrishnan <ramana.radhakrishnan@arm.com>
 
 	* config/arm/arm.c (arm_override_options): Fix braces and formatting from previous 

gcc/Makefile.in

@@ -134,6 +134,7 @@ LANGUAGES = c gcov$(exeext) gcov-dump$(exeext) $(CONFIG_LANGUAGES)
 T_CFLAGS =
 TCFLAGS =
 CFLAGS = @CFLAGS@
+CXXFLAGS = @CXXFLAGS@
 LDFLAGS = @LDFLAGS@
 
 # Flags to determine code coverage. When coverage is disabled, this will
@@ -149,11 +150,15 @@ coverageexts = .{gcda,gcno}
 # off if they wish.
 # LOOSE_WARN are the warning flags to use when compiling something
 # which is only compiled with gcc, such as libgcc.
+# C_LOOSE_WARN is similar, but with C-only warnings.
 # STRICT_WARN are the additional warning flags to
 # apply to the back end and some front ends, which may be compiled
 # with other compilers.
+# C_STRICT_WARN is similar, with C-only warnings.
 LOOSE_WARN = @loose_warn@
+C_LOOSE_WARN = @c_loose_warn@
 STRICT_WARN = @strict_warn@
+C_STRICT_WARN = @c_strict_warn@
 
 # This is set by --enable-checking.  The idea is to catch forgotten
 # "extern" tags in header files.
@@ -169,7 +174,8 @@ VALGRIND_DRIVER_DEFINES = @valgrind_path_defines@
 # This is how we control whether or not the additional warnings are applied.
 .-warn = $(STRICT_WARN)
 build-warn = $(STRICT_WARN)
-GCC_WARN_CFLAGS = $(LOOSE_WARN) $($(@D)-warn) $(NOCOMMON_FLAG) $($@-warn)
+GCC_WARN_CFLAGS = $(LOOSE_WARN) $(C_LOOSE_WARN) $($(@D)-warn) $(if $(filter-out $(STRICT_WARN),$($(@D)-warn)),,$(C_STRICT_WARN)) $(NOCOMMON_FLAG) $($@-warn)
+GCC_WARN_CXXFLAGS = $(LOOSE_WARN) $($(@D)-warn) $(NOCOMMON_FLAG) $($@-warn)
 
 # These files are to have specific diagnostics suppressed, or are not to
 # be subject to -Werror:
@@ -180,13 +186,16 @@ mips-tfile.o-warn = -Wno-error
 
 # All warnings have to be shut off in stage1 if the compiler used then
 # isn't gcc; configure determines that.  WARN_CFLAGS will be either
-# $(GCC_WARN_CFLAGS), or nothing.
+# $(GCC_WARN_CFLAGS), or nothing.  Similarly, WARN_CXXFLAGS will be
+# either $(GCC_WARN_CXXFLAGS), or nothing.
 WARN_CFLAGS = @warn_cflags@
+WARN_CXXFLAGS = @warn_cxxflags@
 
 CPPFLAGS = @CPPFLAGS@
 
 AWK = @AWK@
 CC = @CC@
+CXX = @CXX@
 BISON = @BISON@
 BISONFLAGS =
 FLEX = @FLEX@
@@ -197,12 +206,19 @@ NM = @NM@
 RANLIB = @RANLIB@
 RANLIB_FLAGS = @ranlib_flags@
 
-# The name of the compiler to use.  Currently always $(CC).  In the
-# future this may change to $(CXX).
+# The name of the compiler to use.
+ENABLE_BUILD_WITH_CXX = @ENABLE_BUILD_WITH_CXX@
+ifneq ($(ENABLE_BUILD_WITH_CXX),yes)
 COMPILER = $(CC)
 COMPILER_FLAGS = $(CFLAGS)
 LINKER = $(CC)
 LINKER_FLAGS = $(CFLAGS)
+else
+COMPILER = $(CXX)
+COMPILER_FLAGS = $(CXXFLAGS)
+LINKER = $(CXX)
+LINKER_FLAGS = $(CXXFLAGS)
+endif
 
 # -------------------------------------------
 # Programs which operate on the build machine
@@ -272,6 +288,9 @@ write_entries_to_file = $(shell rm -f $(2) || :) $(shell touch $(2)) \
 # In stage2 and beyond, we force this to "-o $@" since we know we're using gcc.
 OUTPUT_OPTION = @OUTPUT_OPTION@
 
+# Libraries to use on the host.
+HOST_LIBS = @HOST_LIBS@
+
 # This is where we get zlib from.  zlibdir is -L../zlib and zlibinc is
 # -I../zlib, unless we were configured with --with-system-zlib, in which
 # case both are empty.
@@ -330,7 +349,7 @@ GCC_FOR_TARGET = $(STAGE_CC_WRAPPER) ./xgcc -B./ -B$(build_tooldir)/bin/ -isyste
 # This is used instead of ALL_CFLAGS when compiling with GCC_FOR_TARGET.
 # It specifies -B./.
 # It also specifies -isystem ./include to find, e.g., stddef.h.
-GCC_CFLAGS=$(CFLAGS_FOR_TARGET) $(INTERNAL_CFLAGS) $(T_CFLAGS) $(LOOSE_WARN) -Wold-style-definition $($@-warn) -isystem ./include $(TCFLAGS)
+GCC_CFLAGS=$(CFLAGS_FOR_TARGET) $(INTERNAL_CFLAGS) $(T_CFLAGS) $(LOOSE_WARN) $(C_LOOSE_WARN) -Wold-style-definition $($@-warn) -isystem ./include $(TCFLAGS)
 
 # ---------------------------------------------------
 # Programs which produce files for the target machine
@@ -917,16 +936,28 @@ INTERNAL_CFLAGS = -DIN_GCC @CROSS@
 ALL_CFLAGS = $(T_CFLAGS) \
   $(CFLAGS) $(INTERNAL_CFLAGS) $(COVERAGE_FLAGS) $(WARN_CFLAGS) @DEFS@
 
+# The C++ version.
+ALL_CXXFLAGS = $(T_CFLAGS) $(CXXFLAGS) $(INTERNAL_CFLAGS) \
+  $(COVERAGE_FLAGS) $(WARN_CXXFLAGS) @DEFS@
+
 # Likewise.  Put INCLUDES at the beginning: this way, if some autoconf macro
 # puts -I options in CPPFLAGS, our include files in the srcdir will always
 # win against random include files in /usr/include.
 ALL_CPPFLAGS = $(INCLUDES) $(CPPFLAGS)
 
 # This is the variable to use when using $(COMPILER).
+ifneq ($(ENABLE_BUILD_WITH_CXX),yes)
 ALL_COMPILERFLAGS = $(ALL_CFLAGS)
+else
+ALL_COMPILERFLAGS = $(ALL_CXXFLAGS)
+endif
 
 # This is the variable to use when using $(LINKER).
+ifneq ($(ENABLE_BUILD_WITH_CXX),yes)
 ALL_LINKERFLAGS = $(ALL_CFLAGS)
+else
+ALL_LINKERFLAGS = $(ALL_CXXFLAGS)
+endif
 
 # Build and host support libraries.
 LIBIBERTY = ../libiberty/libiberty.a
@@ -941,8 +972,9 @@ BUILD_LIBDEPS= $(BUILD_LIBIBERTY)
 
 # How to link with both our special library facilities
 # and the system's installed libraries.
-LIBS = @LIBS@ $(CPPLIB) $(LIBINTL) $(LIBICONV) $(LIBIBERTY) $(LIBDECNUMBER)
-BACKENDLIBS = $(CLOOGLIBS) $(PPLLIBS) $(GMPLIBS) $(PLUGINLIBS)
+LIBS = @LIBS@ $(CPPLIB) $(LIBINTL) $(LIBICONV) $(LIBIBERTY) $(LIBDECNUMBER) \
+	$(HOST_LIBS)
+BACKENDLIBS = $(CLOOGLIBS) $(PPLLIBS) $(GMPLIBS) $(PLUGINLIBS) $(HOST_LIBS)
 # Any system libraries needed just for GNAT.
 SYSLIBS = @GNAT_LIBEXC@
 

gcc/configure.ac

@@ -276,6 +276,7 @@ rm -f a.out a.exe b.out
 # Find the native compiler
 AC_PROG_CC
 AM_PROG_CC_C_O
+AC_PROG_CXX
 ACX_PROG_GNAT([-I"$srcdir"/ada])
 
 # autoconf is lame and doesn't give us any substitution variable for this.
@@ -323,24 +324,30 @@ AC_CHECK_TYPES([__int64], [AC_CHECK_SIZEOF(__int64)])
 # So, we only use -pedantic if we can disable those warnings.
 
 ACX_PROG_CC_WARNING_OPTS(
-	m4_quote(m4_do([-W -Wall -Wwrite-strings -Wstrict-prototypes ],
-		       [-Wmissing-prototypes -Wcast-qual])), [loose_warn])
+	m4_quote(m4_do([-W -Wall -Wwrite-strings -Wcast-qual])), [loose_warn])
 ACX_PROG_CC_WARNING_OPTS(
-	m4_quote(m4_do([-Wold-style-definition -Wc++-compat ], 
-		       [-Wmissing-format-attribute])), [strict_warn])
+	m4_quote(m4_do([-Wstrict-prototypes -Wmissing-prototypes])),
+	[c_loose_warn])
+ACX_PROG_CC_WARNING_OPTS(
+	m4_quote(m4_do([-Wmissing-format-attribute])), [strict_warn])
+ACX_PROG_CC_WARNING_OPTS(
+	m4_quote(m4_do([-Wold-style-definition -Wc++-compat])), [c_strict_warn])
 ACX_PROG_CC_WARNING_ALMOST_PEDANTIC(
 	m4_quote(m4_do([-Wno-long-long -Wno-variadic-macros ], 
 		       [-Wno-overlength-strings])), [strict_warn])
 ACX_PROG_CC_WARNINGS_ARE_ERRORS([manual], [strict_warn])
 
 # The above macros do nothing if the compiler is not GCC.  However, the
-# Makefile has more goo to add other flags, so this variabl is used to
-# enables warnings only for GCC.
+# Makefile has more goo to add other flags, so these variables are used
+# to enable warnings only for GCC.
 warn_cflags=
+warn_cxxflags=
 if test "x$GCC" = "xyes"; then
   warn_cflags='$(GCC_WARN_CFLAGS)'
+  warn_cxxflags='$(GCC_WARN_CXXFLAGS)'
 fi
 AC_SUBST(warn_cflags)
+AC_SUBST(warn_cxxflags)
 
 # Enable expensive internal checks
 is_release=
@@ -573,6 +580,13 @@ fi
 # Miscenalleous configure options
 # -------------------------------
 
+# See if we are building gcc with C++.
+AC_ARG_ENABLE(build-with-cxx,
+[  --enable-build-with-cxx build with C++ compiler instead of C compiler],
+ENABLE_BUILD_WITH_CXX=$enableval,
+ENABLE_BUILD_WITH_CXX=no)
+AC_SUBST(ENABLE_BUILD_WITH_CXX)
+
 # With stabs
 AC_ARG_WITH(stabs,
 [  --with-stabs            arrange to use stabs instead of host debug format],
@@ -3749,6 +3763,13 @@ esac],
 AC_SUBST(GGC)
 echo "Using $GGC for garbage collection."
 
+# Libraries to use on the host.  This will normally be set by the top
+# level Makefile.  Here we simply capture the value for our Makefile.
+if test -z "${HOST_LIBS+set}"; then
+  HOST_LIBS=
+fi
+AC_SUBST(HOST_LIBS)
+
 # Use the system's zlib library.
 zlibdir=-L../zlib
 zlibinc="-I\$(srcdir)/../zlib"

gcc/doc/install.texi

@@ -1204,6 +1204,10 @@ opposite effect.  If neither option is specified, the configure script
 will try to guess whether the @code{.init_array} and
 @code{.fini_array} sections are supported and, if they are, use them.
 
+@item --enable-build-with-cxx
+Build GCC using a C++ compiler rather than a C compiler.  This is an
+experimental option which may become the default in a later release.
+
 @item --enable-maintainer-mode
 The build rules that
 regenerate the GCC master message catalog @file{gcc.pot} are normally
@@ -1549,6 +1553,27 @@ linking with a shared copy of PPL, you probably do not need this
 option; shared library dependencies will cause the linker to search
 for the standard C++ library automatically.
 
+@item --with-stage1-ldflags=@var{flags}
+This option may be used to set linker flags to be used when linking
+stage 1 of GCC.  These are also used when linking GCC if configured with
+@option{--disable-bootstrap}.  By default no special flags are used.
+
+@item --with-stage1-libs=@var{libs}
+This option may be used to set libraries to be used when linking stage 1
+of GCC.  These are also used when linking GCC if configured with
+@option{--disable-bootstrap}.  The default is the argument to
+@option{--with-host-libstdcxx}, if specified.
+
+@item --with-boot-ldflags=@var{flags}
+This option may be used to set linker flags to be used when linking
+stage 2 and later when bootstrapping GCC.  By default no special flags
+are used.
+
+@item --with-boot-libs=@var{libs}
+This option may be used to set libraries to be used when linking stage 2
+and later when bootstrapping GCC.  The default is the argument to
+@option{--with-host-libstdcxx}, if specified.
+
 @item --with-debug-prefix-map=@var{map}
 Convert source directory names using @option{-fdebug-prefix-map} when
 building runtime libraries.  @samp{@var{map}} is a space-separated