From: Jakub Jelinek Date: Fri, 21 Jan 2022 21:44:53 +0000 (+0100) Subject: c-family: Fix up a -Wformat regression [PR104148] X-Git-Tag: upstream/12.2.0~1887 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f36efe71bef8ddf72306aca313d28759434cf97a;p=platform%2Fupstream%2Fgcc.git c-family: Fix up a -Wformat regression [PR104148] As can be seen on the testcase, GCC 11 no longer warns if the format string is wrapped inside of ()s. This regressed with r11-2457-gdf5cf47a978, which added if (TREE_NO_WARNING (param)) return; to check_function_arguments_recurse. That function is used with a callback for two cases, for -Wformat and for -Wnonnull. For the latter it is desirable to not warn in parameters or their subexpressions where that warning is suppressed, but for -Wformat the function is used solely to discover the string literals if any so that the c-format.cc code can diagnose them. I believe no warning suppression should stand in the way of that, -Wformat* warnings should be decided from warning suppression on the CALL_EXPR only. In the PR Martin argued that now that we have specialized warning_suppressed_p we should use it, so instead of adding a bool arg to check_function_arguments_recurse I've added opt_code to the function, but will defer the warning_suppressed_p change to him. For OPT_Wformat_ we don't want to call it anyway at all (as I said, I think there should be no suppression for it during the string discovery, there isn't just one -Wformat= option, there are many and warning_suppression_p even with no_warnings actually tests the TREE_NO_WARNING bit). Initially, I thought I'd restrict also call to fn with format_arg attribute handling in check_function_arguments_recurse to OPT_Wformat_ only, but after looking around, it perhaps is intentional that way, most functions with format_arg attribute don't have nonnull attribute for that arg too, various gettext implementations handle NULL argument by passing it through, but when result of gettext (NULL) etc. is passed to non-NULL argument, it makes sense to warn. 2022-01-21 Jakub Jelinek PR c++/104148 * c-common.h (check_function_arguments_recurse): Add for_format arg. * c-common.cc (check_function_nonnull): Pass false to check_function_arguments_recurse's last argument. (check_function_arguments_recurse): Add for_format argument, if true, don't stop on warning_suppressed_p. * c-format.cc (check_format_info): Pass true to check_function_arguments_recurse's last argument. * c-c++-common/Wformat-pr104148.c: New test. --- diff --git a/gcc/c-family/c-common.cc b/gcc/c-family/c-common.cc index f56f6df..bf0749b 100644 --- a/gcc/c-family/c-common.cc +++ b/gcc/c-family/c-common.cc @@ -5592,7 +5592,7 @@ check_function_nonnull (nonnull_arg_ctx &ctx, int nargs, tree *argarray) firstarg = 1; if (!closure) check_function_arguments_recurse (check_nonnull_arg, &ctx, argarray[0], - firstarg); + firstarg, OPT_Wnonnull); } tree attrs = lookup_attribute ("nonnull", TYPE_ATTRIBUTES (ctx.fntype)); @@ -5611,7 +5611,7 @@ check_function_nonnull (nonnull_arg_ctx &ctx, int nargs, tree *argarray) if (a != NULL_TREE) for (int i = firstarg; i < nargs; i++) check_function_arguments_recurse (check_nonnull_arg, &ctx, argarray[i], - i + 1); + i + 1, OPT_Wnonnull); else { /* Walk the argument list. If we encounter an argument number we @@ -5627,7 +5627,8 @@ check_function_nonnull (nonnull_arg_ctx &ctx, int nargs, tree *argarray) if (a != NULL_TREE) check_function_arguments_recurse (check_nonnull_arg, &ctx, - argarray[i], i + 1); + argarray[i], i + 1, + OPT_Wnonnull); } } return ctx.warned_p; @@ -6095,14 +6096,16 @@ check_function_arguments (location_t loc, const_tree fndecl, const_tree fntype, /* Generic argument checking recursion routine. PARAM is the argument to be checked. PARAM_NUM is the number of the argument. CALLBACK is invoked - once the argument is resolved. CTX is context for the callback. */ + once the argument is resolved. CTX is context for the callback. + OPT is the warning for which this is done. */ void check_function_arguments_recurse (void (*callback) (void *, tree, unsigned HOST_WIDE_INT), void *ctx, tree param, - unsigned HOST_WIDE_INT param_num) + unsigned HOST_WIDE_INT param_num, + opt_code opt) { - if (warning_suppressed_p (param)) + if (opt != OPT_Wformat_ && warning_suppressed_p (param)) return; if (CONVERT_EXPR_P (param) @@ -6111,7 +6114,8 @@ check_function_arguments_recurse (void (*callback) { /* Strip coercion. */ check_function_arguments_recurse (callback, ctx, - TREE_OPERAND (param, 0), param_num); + TREE_OPERAND (param, 0), param_num, + opt); return; } @@ -6148,7 +6152,8 @@ check_function_arguments_recurse (void (*callback) if (i == format_num) { check_function_arguments_recurse (callback, ctx, - inner_arg, param_num); + inner_arg, param_num, + opt); found_format_arg = true; break; } @@ -6170,10 +6175,10 @@ check_function_arguments_recurse (void (*callback) /* Check both halves of the conditional expression. */ check_function_arguments_recurse (callback, ctx, TREE_OPERAND (param, 1), - param_num); + param_num, opt); check_function_arguments_recurse (callback, ctx, TREE_OPERAND (param, 2), - param_num); + param_num, opt); return; } } diff --git a/gcc/c-family/c-common.h b/gcc/c-family/c-common.h index 28c73fe..a8d6f82 100644 --- a/gcc/c-family/c-common.h +++ b/gcc/c-family/c-common.h @@ -853,7 +853,8 @@ extern void check_function_arguments_recurse (void (*) (void *, tree, unsigned HOST_WIDE_INT), void *, tree, - unsigned HOST_WIDE_INT); + unsigned HOST_WIDE_INT, + opt_code); extern bool check_builtin_function_arguments (location_t, vec, tree, tree, int, tree *); extern void check_function_format (const_tree, tree, int, tree *, diff --git a/gcc/c-family/c-format.cc b/gcc/c-family/c-format.cc index a2affda..98f28c0 100644 --- a/gcc/c-family/c-format.cc +++ b/gcc/c-family/c-format.cc @@ -1531,7 +1531,7 @@ check_format_info (function_format_info *info, tree params, format_ctx.arglocs = arglocs; check_function_arguments_recurse (check_format_arg, &format_ctx, - format_tree, arg_num); + format_tree, arg_num, OPT_Wformat_); location_t loc = format_ctx.res->format_string_loc; diff --git a/gcc/testsuite/c-c++-common/Wformat-pr104148.c b/gcc/testsuite/c-c++-common/Wformat-pr104148.c new file mode 100644 index 0000000..6786463 --- /dev/null +++ b/gcc/testsuite/c-c++-common/Wformat-pr104148.c @@ -0,0 +1,33 @@ +/* PR c++/104148 */ +/* { dg-do compile } */ +/* { dg-options "-Wformat" } */ + +char *foo (const char *) __attribute__((format_arg(1))); +void bar (const char *, ...) __attribute__((format(printf, 1, 2))); + +void +baz (int x) +{ + bar ("%ld", x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + bar (x ? "%ld" : "%ld", x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + bar (x ? "%ld" : "%lld", x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + /* { dg-warning "format '%lld' expects argument of type 'long long int', but argument 2 has type 'int'" "" { target *-*-* } .-1 } */ + bar (foo ("%ld"), x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + bar (x ? foo ("%ld") : "%ld", x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + bar (x ? foo ("%ld") : "%lld", x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + /* { dg-warning "format '%lld' expects argument of type 'long long int', but argument 2 has type 'int'" "" { target *-*-* } .-1 } */ + bar (foo (x ? "%ld" : "%ld"), x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + bar (foo (x ? "%ld" : "%lld"), x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + /* { dg-warning "format '%lld' expects argument of type 'long long int', but argument 2 has type 'int'" "" { target *-*-* } .-1 } */ + bar (("%ld"), x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + bar ((x ? "%ld" : "%ld"), x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + bar ((x ? "%ld" : "%lld"), x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + /* { dg-warning "format '%lld' expects argument of type 'long long int', but argument 2 has type 'int'" "" { target *-*-* } .-1 } */ + bar ((foo ("%ld")), x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + bar ((x ? foo ("%ld") : "%ld"), x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + bar ((x ? foo ("%ld") : "%lld"), x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + /* { dg-warning "format '%lld' expects argument of type 'long long int', but argument 2 has type 'int'" "" { target *-*-* } .-1 } */ + bar ((foo (x ? "%ld" : "%ld")), x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + bar ((foo (x ? "%ld" : "%lld")), x); /* { dg-warning "format '%ld' expects argument of type 'long int', but argument 2 has type 'int'" } */ + /* { dg-warning "format '%lld' expects argument of type 'long long int', but argument 2 has type 'int'" "" { target *-*-* } .-1 } */ +}