diff --git a/srcpkgs/llvm11/template b/srcpkgs/llvm11/template
index b13923002af..f0f9c1eeda4 100644
--- a/srcpkgs/llvm11/template
+++ b/srcpkgs/llvm11/template
@@ -121,6 +121,8 @@ post_patch() {
 			;;
 	esac
 
+	# update config.guess for better platform detection
+	cp $XBPS_COMMONDIR/environment/configure/automake/config.guess ${wrksrc}/cmake
 }
 
 pre_configure() {