Don't check Makefile directives

Author: jieyouxu

src/tools/compiletest/src/header.rs

@@ -962,6 +962,17 @@ fn iter_header(
         // First try to accept `ui_test` style comments
         } else if let Some((header_revision, original_directive_line)) = line_directive(comment, ln)
         {
+            // Let Makefiles and non-rs files just get handled in the regular way.
+            if testfile.extension().map(|e| e != "rs").unwrap_or(true) {
+                it(HeaderLine {
+                    line_number,
+                    original_line,
+                    header_revision,
+                    directive: original_directive_line,
+                });
+                continue;
+            }
+
             let directive_ln = original_directive_line.trim();
 
             if let Some((directive_name, _)) = directive_ln.split_once([':', ' ']) {