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

1 files changed, 27 insertions, 6 deletions

diff --git a/gcc/configure.ac b/gcc/configure.ac
index 341571c..f0a239b 100644
--- a/gcc/configure.ac
+++ b/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"