Handle a missing c++ too.

diff --git a/configure.ac b/configure.ac
index 3330eb90ef83a450c3876c3d9c07238b8f81a90a..85b9791445f54d8184fa842616c3aa69d019b9a5 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -203,9 +203,9 @@ AC_ARG_ENABLE(simd,
 if test x"$enable_simd" != x"no"; then
     # For x86-64 SIMD, g++ >=5 or clang++ >=7 is required
     if test x"$build_cpu" = x"x86_64"; then
+       CXX_OK=
        if test x"$CXX" != x""; then
-           CXX_OK=
-           CXX_VERSION=`$CXX --version | head -n 1`
+           CXX_VERSION=`$CXX --version 2>/dev/null | head -n 1`
            case "$CXX_VERSION" in
            g++*)
                CXX_VERSION=`$CXX -dumpversion | sed 's/\..*//g'`
@@ -220,16 +220,21 @@ if test x"$enable_simd" != x"no"; then
                    CXX_OK=yes
                fi
                ;;
+           *)
+               CXX_VERSION='Unknown'
+               ;;
            esac
-
-           if test x"$CXX_OK" = x"yes"; then
-               # AC_MSG_RESULT() is called below.
-               SIMD="$SIMD x86_64"
-           else
-               AC_MSG_RESULT(error)
-               AC_MSG_ERROR([Failed to find g++ >=5 or clang++ >=7 for SIMD optimizations.
+       else
+           CXX='No c++'
+           CXX_VERSION='Unknown'
+       fi
+       if test x"$CXX_OK" = x"yes"; then
+           # AC_MSG_RESULT() is called below.
+           SIMD="$SIMD x86_64"
+       else
+           AC_MSG_RESULT(error)
+           AC_MSG_ERROR([Failed to find g++ >=5 or clang++ >=7 for SIMD optimizations.
 Specify --disable-simd to continue without it. ($CXX, $CXX_VERSION)])
-           fi
        fi
     elif test x"$enable_simd" = x"yes"; then
         AC_MSG_RESULT(unavailable)