diff options
Diffstat (limited to 'gcc/c-common.c')
| -rw-r--r-- | gcc/c-common.c | 25 |
1 files changed, 23 insertions, 2 deletions
diff --git a/gcc/c-common.c b/gcc/c-common.c index 7359b04..5e7666a 100644 --- a/gcc/c-common.c +++ b/gcc/c-common.c @@ -2345,8 +2345,29 @@ check_format_info (status, info, params) /* Functions taking a va_list normally pass a non-literal format string. These functions typically are declared with first_arg_num == 0, so avoid warning in those cases. */ - if (info->first_arg_num != 0 && warn_format_nonliteral) - status_warning (status, "format not a string literal, argument types not checked"); + if (!(format_types[info->format_type].flags & FMT_FLAG_ARG_CONVERT)) + { + /* For strftime-like formats, warn for not checking the format + string; but there are no arguments to check. */ + if (warn_format_nonliteral) + status_warning (status, "format not a string literal, format string not checked"); + } + else if (info->first_arg_num != 0) + { + /* If there are no arguments for the format at all, we may have + printf (foo) which is likely to be a security hole. */ + while (arg_num + 1 < info->first_arg_num) + { + if (params == 0) + break; + params = TREE_CHAIN (params); + ++arg_num; + } + if (params == 0 && warn_format_nonliteral) + status_warning (status, "format not a string literal and no format arguments"); + else if (warn_format_nonliteral) + status_warning (status, "format not a string literal, argument types not checked"); + } } /* If there were extra arguments to the format, normally warn. However, |