Bug 1177759 - make clang version detection robust for higher versions…

…, r=ttaubert

Differential Revision: https://nss-review.dev.mozaws.net/D171

--HG--
extra : rebase_source : 94dce64fd68dd7ad91634a97f3f8b1512e52a832
extra : amend_source : 1d8eecd185c6721a7f16c57a0cd09c8375de31ed

coreconf/sanitizers.sh

@@ -21,8 +21,8 @@ enable_sanitizer()
 
 enable_sancov()
 {
-    local clang_version=$($CC --version | grep -oE 'clang version (3\.9\.|4\.)')
-    if [ -z "$clang_version" ]; then
+    local clang_version=$($CC --version | grep -oE '([0-9]{1,}\.)+[0-9]{1,}')
+    if [[ ${clang_version:0:1} -lt 4 && ${clang_version:0:1} -eq 3 && ${clang_version:2:1} -lt 9 ]]; then
         echo "Need at least clang-3.9 (better 4.0) for sancov." 1>&2
         exit 1
     fi