Replace the old --with-cxx-* configure options with a single --with-gcc-toolchain
that just uses the new toolchain probing logic. This fixes linking with -m32 on
64 bit systems (the /32 dir was not being added to the search).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149651 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/projects/sample/autoconf/configure.ac b/projects/sample/autoconf/configure.ac
index a19e87d..1caff51 100644
--- a/projects/sample/autoconf/configure.ac
+++ b/projects/sample/autoconf/configure.ac
@@ -745,33 +745,15 @@
 AC_DEFINE_UNQUOTED(C_INCLUDE_DIRS,"$withval",
                    [Directories clang will search for headers])
 
-AC_ARG_WITH(cxx-include-root,
-  AS_HELP_STRING([--with-cxx-include-root],
-    [Directory with the libstdc++ headers.]),,
+# Clang normally uses the system c++ headers and libraries. With this option,
+# clang will use the ones provided by a gcc installation instead. This option should
+# be passed the same value that was used with --prefix when configuring gcc.
+AC_ARG_WITH(gcc-toolchain,
+  AS_HELP_STRING([--with-gcc-toolchain],
+    [Directory where gcc is installed.]),,
     withval="")
-AC_DEFINE_UNQUOTED(CXX_INCLUDE_ROOT,"$withval",
-                   [Directory with the libstdc++ headers.])
-
-AC_ARG_WITH(cxx-include-arch,
-  AS_HELP_STRING([--with-cxx-include-arch],
-    [Architecture of the libstdc++ headers.]),,
-    withval="")
-AC_DEFINE_UNQUOTED(CXX_INCLUDE_ARCH,"$withval",
-                   [Arch the libstdc++ headers.])
-
-AC_ARG_WITH(cxx-include-32bit-dir,
-  AS_HELP_STRING([--with-cxx-include-32bit-dir],
-    [32 bit multilib dir.]),,
-    withval="")
-AC_DEFINE_UNQUOTED(CXX_INCLUDE_32BIT_DIR,"$withval",
-                   [32 bit multilib directory.])
-
-AC_ARG_WITH(cxx-include-64bit-dir,
-  AS_HELP_STRING([--with-cxx-include-64bit-dir],
-    [64 bit multilib directory.]),,
-    withval="")
-AC_DEFINE_UNQUOTED(CXX_INCLUDE_64BIT_DIR,"$withval",
-                   [64 bit multilib directory.])
+AC_DEFINE_UNQUOTED(GCC_INSTALL_PREFIX,"$withval",
+                   [Directory where gcc is installed.])
 
 dnl Allow linking of LLVM with GPLv3 binutils code.
 AC_ARG_WITH(binutils-include,
diff --git a/projects/sample/configure b/projects/sample/configure
index 418f2ea..dab1dc5 100755
--- a/projects/sample/configure
+++ b/projects/sample/configure
@@ -1426,12 +1426,7 @@
                           resource files
   --with-c-include-dirs   Colon separated list of directories clang will
                           search for headers
-  --with-cxx-include-root Directory with the libstdc++ headers.
-  --with-cxx-include-arch Architecture of the libstdc++ headers.
-  --with-cxx-include-32bit-dir
-                          32 bit multilib dir.
-  --with-cxx-include-64bit-dir
-                          64 bit multilib directory.
+  --with-gcc-toolchain    Directory where gcc is installed.
   --with-binutils-include Specify path to binutils/include/ containing
                           plugin-api.h file for gold plugin.
   --with-bug-report-url   Specify the URL where bug reports should be
@@ -5493,59 +5488,20 @@
 _ACEOF
 
 
+# Clang normally uses the system c++ headers and libraries. With this option,
+# clang will use the ones provided by a gcc installation instead. This option should
+# be passed the same value that was used with --prefix when configuring gcc.
 
-# Check whether --with-cxx-include-root was given.
-if test "${with_cxx_include_root+set}" = set; then
-  withval=$with_cxx_include_root;
+# Check whether --with-gcc-toolchain was given.
+if test "${with_gcc_toolchain+set}" = set; then
+  withval=$with_gcc_toolchain;
 else
   withval=""
 fi
 
 
 cat >>confdefs.h <<_ACEOF
-#define CXX_INCLUDE_ROOT "$withval"
-_ACEOF
-
-
-
-# Check whether --with-cxx-include-arch was given.
-if test "${with_cxx_include_arch+set}" = set; then
-  withval=$with_cxx_include_arch;
-else
-  withval=""
-fi
-
-
-cat >>confdefs.h <<_ACEOF
-#define CXX_INCLUDE_ARCH "$withval"
-_ACEOF
-
-
-
-# Check whether --with-cxx-include-32bit-dir was given.
-if test "${with_cxx_include_32bit_dir+set}" = set; then
-  withval=$with_cxx_include_32bit_dir;
-else
-  withval=""
-fi
-
-
-cat >>confdefs.h <<_ACEOF
-#define CXX_INCLUDE_32BIT_DIR "$withval"
-_ACEOF
-
-
-
-# Check whether --with-cxx-include-64bit-dir was given.
-if test "${with_cxx_include_64bit_dir+set}" = set; then
-  withval=$with_cxx_include_64bit_dir;
-else
-  withval=""
-fi
-
-
-cat >>confdefs.h <<_ACEOF
-#define CXX_INCLUDE_64BIT_DIR "$withval"
+#define GCC_INSTALL_PREFIX "$withval"
 _ACEOF
 
 
@@ -10409,7 +10365,7 @@
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<EOF
-#line 10412 "configure"
+#line 10368 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H