diff --git a/make/autoconf/toolchain.m4 b/make/autoconf/toolchain.m4
index 57064df1ed75f..12d450cc708cd 100644
--- a/make/autoconf/toolchain.m4
+++ b/make/autoconf/toolchain.m4
@@ -678,6 +678,9 @@ AC_DEFUN_ONCE([TOOLCHAIN_DETECT_TOOLCHAIN_EXTRA],
       test_metal=`$METAL --version 2>&1`
       if test $? -ne 0; then
         AC_MSG_RESULT([no])
+        AC_MSG_NOTICE([A full XCode is required to build the JDK (not only command line tools)])
+        AC_MSG_NOTICE([If you have XCode installed, you might need to reset the Xcode active developer directory])
+        AC_MSG_NOTICE([using 'sudo xcode-select -r'])
         AC_MSG_ERROR([XCode tool 'metal' neither found in path nor with xcrun])
       else
         AC_MSG_RESULT([yes, will be using '$METAL'])