Merge pull request #2353 from jszakmeister/fix-unused-var-warnings-in-release

Fix several unused variable warnings in the release build.

src/nvim/tag.c

@@ -2783,7 +2783,11 @@ int get_tags(list_T *list, char_u *pat)
   if (ret == OK && num_matches > 0) {
     for (i = 0; i < num_matches; ++i) {
       int parse_result = parse_match(matches[i], &tp);
+
+      // Avoid an unused variable warning in release builds.
+      (void) parse_result;
       assert(parse_result == OK);
+
       is_static = test_for_static(&tp);
 
       /* Skip pseudo-tag lines. */

src/nvim/undo.c

@@ -2773,7 +2773,10 @@ void u_undoline(void)
 void u_blockfree(buf_T *buf)
 {
   while (buf->b_u_oldhead != NULL) {
+#ifndef NDEBUG
     u_header_T *previous_oldhead = buf->b_u_oldhead;
+#endif
+
     u_freeheader(buf, buf->b_u_oldhead, NULL);
     assert(buf->b_u_oldhead != previous_oldhead);
   }