diff --git a/config/lyxinclude.m4 b/config/lyxinclude.m4
index 1bf9def1c3..164b2f7a89 100644
--- a/config/lyxinclude.m4
+++ b/config/lyxinclude.m4
@@ -383,6 +383,10 @@ if test x$GXX = xyes; then
   if test x$CLANG = xno; then
     dnl Useful for global version info
     gxx_version=`${CXX} -dumpversion`
+    case $gxx_version in
+	*.*) ;;
+	*) gxx_version=`${CXX} -dumpfullversion` ;;
+    esac
     CXX_VERSION="($gxx_version)"
   else
     gxx_version=clang-$clang_version
diff --git a/status.23x b/status.23x
index 23bd3edb11..a9f823323f 100644
--- a/status.23x
+++ b/status.23x
@@ -195,3 +195,5 @@ What's new
 
 * BUILD/INSTALLATION
 
+- avoid annoying warnings with g++ 9.
+