diff --git a/build/autoconf/clang-plugin.m4 b/build/autoconf/clang-plugin.m4
index edead7789363..acd7b3f23f48 100644
--- a/build/autoconf/clang-plugin.m4
+++ b/build/autoconf/clang-plugin.m4
@@ -95,8 +95,8 @@ if test -n "$ENABLE_CLANG_PLUGIN"; then
     dnl Check for the new ASTMatcher API names.  Since this happened in the
     dnl middle of the 3.8 cycle, our CLANG_VERSION_FULL is impossible to use
     dnl correctly, so we have to detect this at configure time.
-    AC_CACHE_CHECK(for new ASTMatcher names,
-                   ac_cv_have_new_ASTMatcher_names,
+    AC_CACHE_CHECK(for new ASTMatcher API,
+                   ac_cv_have_new_ASTMatcher_api,
         [
             AC_LANG_SAVE
             AC_LANG_CPLUSPLUS