Fix configure's gcc version check. #593

We don't want to test the gcc version on the mac.  It is clang
underneath and it does not report a version >= 4.8.  On High Sierra
it reports 4.2.1

autoconf/configure.ac

@@ -177,17 +177,6 @@ AC_DEFUN([AX_JSC_DIRS],[
     AC_SUBST([MOTIF_HOME])
 ])
 
-dnl add extra paths to find gcc on RHEL 6 systems
-PATH="/opt/rh/devtoolset-3/root/usr/bin:${PATH}"
-dnl add extra paths to find xml headers and X headers on the mac.
-XTRAINCPATHS="-I/usr/include/libxml2/ -I/usr/X11/include"
-CFLAGS="$CFLAGS $XTRAINCPATHS"
-CPPFLAGS="$CPPFLAGS $XTRAINCPATHS"
-
-dnl look for programs we need to compile and run
-AC_PROG_AWK
-AC_PROG_CC
-AC_PROG_CXX
 AC_DEFUN([AX_GCC_VERSION], [
   GCC_VERSION=""
   AS_IF([test "x$GCC" = "xyes"],[
@@ -203,7 +192,32 @@ AC_DEFUN([AX_GCC_VERSION], [
   ])
   AC_SUBST([GCC_VERSION])
 ])
-AX_GCC_VERSION
+
+dnl get the host_os.
+AC_CANONICAL_HOST
+
+dnl add extra paths to find gcc on RHEL 6 systems
+PATH="/opt/rh/devtoolset-3/root/usr/bin:${PATH}"
+dnl add extra paths to find xml headers and X headers on the mac.
+XTRAINCPATHS="-I/usr/include/libxml2/ -I/usr/X11/include"
+CFLAGS="$CFLAGS $XTRAINCPATHS"
+CPPFLAGS="$CPPFLAGS $XTRAINCPATHS"
+
+dnl look for programs we need to compile and run
+AC_PROG_AWK
+AC_PROG_CC
+AC_PROG_CXX
+
+dnl do not test gcc version on mac.  clang as gcc will return version and it's not >= 4.8
+TEST_GCC=yes
+case "${host_os}" in
+    darwin*)
+        TEST_GCC=no
+        ;;
+    *)
+        ;;
+esac
+AS_IF([test "$TEST_GCC" = "yes"],[AX_GCC_VERSION],[])
 dnl if the compiler is gcc, test for gcc >= 4.8
 AS_IF([test "x$GCC_VERSION" = "x"],[],
  [AC_MSG_CHECKING([gcc version >= 4.8])

configure

@@ -635,8 +635,8 @@ CLANG_VERSION
 LLVM_HOME
 CLANG
 LLVM_CONFIG
-PYTHON_EXTRA_LDFLAGS
 PYTHON_EXTRA_LIBS
+PYTHON_EXTRA_LDFLAGS
 PYTHON_SITE_PKG
 PYTHON_LIBS
 PYTHON_CPPFLAGS
@@ -647,14 +647,6 @@ PTHREAD_CC
 ax_pthread_config
 CPP
 SED
-host_os
-host_vendor
-host_cpu
-host
-build_os
-build_vendor
-build_cpu
-build
 LIBXML
 MOTIF_HOME
 X_LIB_DIR
@@ -691,6 +683,14 @@ LDFLAGS
 CFLAGS
 CC
 AWK
+host_os
+host_vendor
+host_cpu
+host
+build_os
+build_vendor
+build_cpu
+build
 target_alias
 host_alias
 build_alias
@@ -2395,6 +2395,80 @@ ac_configure="$SHELL $ac_aux_dir/configure"  # Please don't use this var.
 
 
 
+
+
+
+
+
+# Make sure we can run config.sub.
+$SHELL "$ac_aux_dir/config.sub" sun4 >/dev/null 2>&1 ||
+  as_fn_error $? "cannot run $SHELL $ac_aux_dir/config.sub" "$LINENO" 5
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking build system type" >&5
+$as_echo_n "checking build system type... " >&6; }
+if ${ac_cv_build+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_build_alias=$build_alias
+test "x$ac_build_alias" = x &&
+  ac_build_alias=`$SHELL "$ac_aux_dir/config.guess"`
+test "x$ac_build_alias" = x &&
+  as_fn_error $? "cannot guess build type; you must specify one" "$LINENO" 5
+ac_cv_build=`$SHELL "$ac_aux_dir/config.sub" $ac_build_alias` ||
+  as_fn_error $? "$SHELL $ac_aux_dir/config.sub $ac_build_alias failed" "$LINENO" 5
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_build" >&5
+$as_echo "$ac_cv_build" >&6; }
+case $ac_cv_build in
+*-*-*) ;;
+*) as_fn_error $? "invalid value of canonical build" "$LINENO" 5;;
+esac
+build=$ac_cv_build
+ac_save_IFS=$IFS; IFS='-'
+set x $ac_cv_build
+shift
+build_cpu=$1
+build_vendor=$2
+shift; shift
+# Remember, the first character of IFS is used to create $*,
+# except with old shells:
+build_os=$*
+IFS=$ac_save_IFS
+case $build_os in *\ *) build_os=`echo "$build_os" | sed 's/ /-/g'`;; esac
+
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking host system type" >&5
+$as_echo_n "checking host system type... " >&6; }
+if ${ac_cv_host+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  if test "x$host_alias" = x; then
+  ac_cv_host=$ac_cv_build
+else
+  ac_cv_host=`$SHELL "$ac_aux_dir/config.sub" $host_alias` ||
+    as_fn_error $? "$SHELL $ac_aux_dir/config.sub $host_alias failed" "$LINENO" 5
+fi
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_host" >&5
+$as_echo "$ac_cv_host" >&6; }
+case $ac_cv_host in
+*-*-*) ;;
+*) as_fn_error $? "invalid value of canonical host" "$LINENO" 5;;
+esac
+host=$ac_cv_host
+ac_save_IFS=$IFS; IFS='-'
+set x $ac_cv_host
+shift
+host_cpu=$1
+host_vendor=$2
+shift; shift
+# Remember, the first character of IFS is used to create $*,
+# except with old shells:
+host_os=$*
+IFS=$ac_save_IFS
+case $host_os in *\ *) host_os=`echo "$host_os" | sed 's/ /-/g'`;; esac
 
 
 
@@ -3492,6 +3566,15 @@ ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ex
 ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
 
 
+TEST_GCC=yes
+case "${host_os}" in
+    darwin*)
+        TEST_GCC=no
+        ;;
+    *)
+        ;;
+esac
+if test "$TEST_GCC" = "yes"; then :
 
   GCC_VERSION=""
   if test "x$GCC" = "xyes"; then :
@@ -3521,6 +3604,7 @@ fi
 fi
 
 
+fi
 if test "x$GCC_VERSION" = "x"; then :
 
 else
@@ -5028,77 +5112,6 @@ else
 fi
 
 
-# Make sure we can run config.sub.
-$SHELL "$ac_aux_dir/config.sub" sun4 >/dev/null 2>&1 ||
-  as_fn_error $? "cannot run $SHELL $ac_aux_dir/config.sub" "$LINENO" 5
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking build system type" >&5
-$as_echo_n "checking build system type... " >&6; }
-if ${ac_cv_build+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_build_alias=$build_alias
-test "x$ac_build_alias" = x &&
-  ac_build_alias=`$SHELL "$ac_aux_dir/config.guess"`
-test "x$ac_build_alias" = x &&
-  as_fn_error $? "cannot guess build type; you must specify one" "$LINENO" 5
-ac_cv_build=`$SHELL "$ac_aux_dir/config.sub" $ac_build_alias` ||
-  as_fn_error $? "$SHELL $ac_aux_dir/config.sub $ac_build_alias failed" "$LINENO" 5
-
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_build" >&5
-$as_echo "$ac_cv_build" >&6; }
-case $ac_cv_build in
-*-*-*) ;;
-*) as_fn_error $? "invalid value of canonical build" "$LINENO" 5;;
-esac
-build=$ac_cv_build
-ac_save_IFS=$IFS; IFS='-'
-set x $ac_cv_build
-shift
-build_cpu=$1
-build_vendor=$2
-shift; shift
-# Remember, the first character of IFS is used to create $*,
-# except with old shells:
-build_os=$*
-IFS=$ac_save_IFS
-case $build_os in *\ *) build_os=`echo "$build_os" | sed 's/ /-/g'`;; esac
-
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking host system type" >&5
-$as_echo_n "checking host system type... " >&6; }
-if ${ac_cv_host+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test "x$host_alias" = x; then
-  ac_cv_host=$ac_cv_build
-else
-  ac_cv_host=`$SHELL "$ac_aux_dir/config.sub" $host_alias` ||
-    as_fn_error $? "$SHELL $ac_aux_dir/config.sub $host_alias failed" "$LINENO" 5
-fi
-
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_host" >&5
-$as_echo "$ac_cv_host" >&6; }
-case $ac_cv_host in
-*-*-*) ;;
-*) as_fn_error $? "invalid value of canonical host" "$LINENO" 5;;
-esac
-host=$ac_cv_host
-ac_save_IFS=$IFS; IFS='-'
-set x $ac_cv_host
-shift
-host_cpu=$1
-host_vendor=$2
-shift; shift
-# Remember, the first character of IFS is used to create $*,
-# except with old shells:
-host_os=$*
-IFS=$ac_save_IFS
-case $host_os in *\ *) host_os=`echo "$host_os" | sed 's/ /-/g'`;; esac
-
-
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for a sed that does not truncate output" >&5
 $as_echo_n "checking for a sed that does not truncate output... " >&6; }
 if ${ac_cv_path_SED+:} false; then :
@@ -6199,13 +6212,13 @@ $as_echo "$PYTHON_SITE_PKG" >&6; }
 	#
 	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking python extra libraries" >&5
 $as_echo_n "checking python extra libraries... " >&6; }
-	if test -z "$PYTHON_EXTRA_LIBS"; then
+	if test -z "$PYTHON_EXTRA_LDFLAGS"; then
-	   PYTHON_EXTRA_LIBS=`$PYTHON -c "import distutils.sysconfig; \
+	   PYTHON_EXTRA_LDFLAGS=`$PYTHON -c "import distutils.sysconfig; \
                 conf = distutils.sysconfig.get_config_var; \
                 print (conf('LIBS') + ' ' + conf('SYSLIBS'))"`
 	fi
-	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $PYTHON_EXTRA_LIBS" >&5
+	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $PYTHON_EXTRA_LDFLAGS" >&5
-$as_echo "$PYTHON_EXTRA_LIBS" >&6; }
+$as_echo "$PYTHON_EXTRA_LDFLAGS" >&6; }
 
 
 	#
@@ -6213,13 +6226,13 @@ $as_echo "$PYTHON_EXTRA_LIBS" >&6; }
 	#
 	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking python extra linking flags" >&5
 $as_echo_n "checking python extra linking flags... " >&6; }
-	if test -z "$PYTHON_EXTRA_LDFLAGS"; then
+	if test -z "$PYTHON_EXTRA_LIBS"; then
-		PYTHON_EXTRA_LDFLAGS=`$PYTHON -c "import distutils.sysconfig; \
+		PYTHON_EXTRA_LIBS=`$PYTHON -c "import distutils.sysconfig; \
 			conf = distutils.sysconfig.get_config_var; \
 			print (conf('LINKFORSHARED'))"`
 	fi
-	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $PYTHON_EXTRA_LDFLAGS" >&5
+	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $PYTHON_EXTRA_LIBS" >&5
-$as_echo "$PYTHON_EXTRA_LDFLAGS" >&6; }
+$as_echo "$PYTHON_EXTRA_LIBS" >&6; }
 
 
 	#