Clear CXX and TEST_CXX if C++ link test fails

Since the C++ compiler is used only for testing, use TEST_CXX as the C++
compiler if available.  If C++ link test fails, clear both CXX and
TEST_CXX so that the C++ compiler isn't used for glibc build nor test.

Tested for m68k-linux-gnu-coldfire build and native build on x86-64.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>

diff --git a/configure b/configure
index fbfe849474bee5ce6ddc04b0d8eb294630739905..37877d5b97a158b193ebbdc3b52456d29f5e74e5 100755 (executable)
--- a/configure
+++ b/configure
@@ -4301,10 +4301,8 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
 if test -z "$TEST_CXX"; then
-  saved_CXX=
   TEST_CXX="$CXX"
 else
-  saved_CXX="$CXX"
   CXX="$TEST_CXX"
 fi
 # It's useless to us if it can't link programs (e.g. missing -lstdc++).
@@ -4382,10 +4380,7 @@ fi
 printf "%s\n" "$libc_cv_cxx_link_ok" >&6; }
 if test $libc_cv_cxx_link_ok != yes
 then :
-  CXX=
-fi
-if test -n "$saved_CXX"; then
-  CXX="$saved_CXX"
+  CXX=; TEST_CXX=
 fi
 
 if test "`cd $srcdir; pwd -P`" = "`pwd -P`"; then

diff --git a/configure.ac b/configure.ac
index 1b0e07dfabbf98e7f0bb7ce67b01c0eab1477787..dca8991fbf1ac4202e1737782f8aef9193ae5cff 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -78,10 +78,8 @@ AC_PROG_CXX
 AC_ARG_VAR([TEST_CXX],
           [C++ compiler for testing])
 if test -z "$TEST_CXX"; then
-  saved_CXX=
   TEST_CXX="$CXX"
 else
-  saved_CXX="$CXX"
   CXX="$TEST_CXX"
 fi
 # It's useless to us if it can't link programs (e.g. missing -lstdc++).
@@ -110,10 +108,7 @@ main()
   LDFLAGS="$old_LDFLAGS"
 fi
 AC_LANG_POP([C++])])
-AS_IF([test $libc_cv_cxx_link_ok != yes], [CXX=])
-if test -n "$saved_CXX"; then
-  CXX="$saved_CXX"
-fi
+AS_IF([test $libc_cv_cxx_link_ok != yes], [CXX=; TEST_CXX=])
 
 if test "`cd $srcdir; pwd -P`" = "`pwd -P`"; then
   AC_MSG_ERROR([you must configure in a separate build directory])