Fix a UB in parse_format_specs when begin is null

fmtlib · Dec 18, 2021 · 659de77 · 659de77
1 parent 51b14b6
commit 659de77
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/include/fmt/core.h b/include/fmt/core.h
@@ -2487,7 +2487,7 @@ FMT_CONSTEXPR FMT_INLINE auto parse_format_specs(const Char* begin,
                                                  const Char* end,
                                                  SpecHandler&& handler)
     -> const Char* {
-  if (begin + 1 < end && begin[1] == '}' && is_ascii_letter(*begin) &&
+  if (1 < end - begin && begin[1] == '}' && is_ascii_letter(*begin) &&
       *begin != 'L') {
     presentation_type type = parse_presentation_type(*begin++);
     if (type == presentation_type::none)