--- a/make/autoconf/jdk-version.m4	Tue Oct 29 11:33:25 2019 +0100
+++ b/make/autoconf/jdk-version.m4	Tue Oct 29 08:26:55 2019 -0700
@@ -162,7 +162,9 @@
     AC_MSG_ERROR([--with-vendor-vm-bug-url must have a value])
   elif [ ! [[ $with_vendor_vm_bug_url =~ ^[[:print:]]*$ ]] ]; then
     AC_MSG_ERROR([--with-vendor-vm-bug-url contains non-printing characters: $with_vendor_vm_bug_url])
-  else
+  elif test "x$with_vendor_vm_bug_url" != x; then
+    # Only set VENDOR_URL_VM_BUG if '--with-vendor-vm-bug-url' was used and is not empty.
+    # Otherwise we will use the value from "version-numbers" included above.
     VENDOR_URL_VM_BUG="$with_vendor_vm_bug_url"
   fi
   AC_SUBST(VENDOR_URL_VM_BUG)