From patchwork Sat Nov 27 22:18:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniil Stas X-Patchwork-Id: 48231 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id D2F933857C6D for ; Sat, 27 Nov 2021 22:19:17 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org D2F933857C6D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1638051557; bh=VllshgM3vS66J7mppPb/MqH5+YHI8d4yWTpzPqJSyP0=; h=To:Subject:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:Cc:From; b=hfjNsoRDElCJHj5G5x8QyTK1WamqODuQPHGR8uX+d31BYs5tZ8nqwDxqWRoS3p0FH RnOF/jJWqVrr2SYLPcEnuru2qCF6AEyW8ssf9ifAqIrn1Sxj6+sVfoR469b4EnFkXb R/36bOe69Ez38ZrqtbuXTBm99j9gkO8XBGyvliSk= X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from mout01.posteo.de (mout01.posteo.de [185.67.36.65]) by sourceware.org (Postfix) with ESMTPS id 4D94E3858C3A for ; Sat, 27 Nov 2021 22:18:47 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 4D94E3858C3A Received: from submission (posteo.de [89.146.220.130]) by mout01.posteo.de (Postfix) with ESMTPS id A50D3240026 for ; Sat, 27 Nov 2021 23:18:45 +0100 (CET) Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 4J1mGr2nHQz6tn8; Sat, 27 Nov 2021 23:18:44 +0100 (CET) To: gcc-patches@gcc.gnu.org Subject: [PATCH v4] c-format: Add -Wformat-int-precision option [PR80060] Date: Sat, 27 Nov 2021 22:18:23 +0000 Message-Id: <20211127221823.301408-1-daniil.stas@posteo.net> MIME-Version: 1.0 X-Spam-Status: No, score=-12.4 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Daniil Stas via Gcc-patches From: Daniil Stas Reply-To: Daniil Stas Cc: "Joseph S. Myers" , Daniil Stas Errors-To: gcc-patches-bounces+patchwork=sourceware.org@gcc.gnu.org Sender: "Gcc-patches" This option is enabled by default when -Wformat option is enabled. A user can specify -Wno-format-int-precision to disable emitting warnings when passing an argument of an incompatible integer type to a 'd', 'i', 'b', 'B', 'o', 'u', 'x', or 'X' conversion specifier when it has the same precision as the expected type. Signed-off-by: Daniil Stas gcc/c-family/ChangeLog: * c-format.c (check_format_types): Don't emit warnings when passing an argument of an incompatible integer type to a 'd', 'i', 'b', 'B', 'o', 'u', 'x', or 'X' conversion specifier when it has the same precision as the expected type if -Wno-format-int-precision option is specified. * c.opt: Add -Wformat-int-precision option. gcc/ChangeLog: * doc/invoke.texi: Add -Wformat-int-precision option description. gcc/testsuite/ChangeLog: * c-c++-common/Wformat-int-precision-1.c: New test. * c-c++-common/Wformat-int-precision-2.c: New test. --- Changes for v4: - Added 'b' and 'B' format specifiers to the option descriptions. Changes for v3: - Added additional @code{} derictives to the documentation where needed. - Changed tests to run on "! long_neq_int" target instead of "lp64". - Added a test case to check that gcc still emits warnings for arguments with different precision even with -Wno-format-int-precision option enabled. Changes for v2: - Changed the option name to -Wformat-int-precision. - Changed the option description as was suggested by Martin. - Changed Wformat-int-precision-2.c to use dg-bogus instead of previous invalid syntax. gcc/c-family/c-format.c | 2 +- gcc/c-family/c.opt | 6 ++++++ gcc/doc/invoke.texi | 17 ++++++++++++++++- .../c-c++-common/Wformat-int-precision-1.c | 7 +++++++ .../c-c++-common/Wformat-int-precision-2.c | 8 ++++++++ 5 files changed, 38 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/c-c++-common/Wformat-int-precision-1.c create mode 100644 gcc/testsuite/c-c++-common/Wformat-int-precision-2.c diff --git a/gcc/c-family/c-format.c b/gcc/c-family/c-format.c index e735e092043..c66787f931f 100644 --- a/gcc/c-family/c-format.c +++ b/gcc/c-family/c-format.c @@ -4248,7 +4248,7 @@ check_format_types (const substring_loc &fmt_loc, && (!pedantic || i < 2) && char_type_flag) continue; - if (types->scalar_identity_flag + if ((types->scalar_identity_flag || !warn_format_int_precision) && (TREE_CODE (cur_type) == TREE_CODE (wanted_type) || (INTEGRAL_TYPE_P (cur_type) && INTEGRAL_TYPE_P (wanted_type))) diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt index 4b8a094b206..d7d952765c6 100644 --- a/gcc/c-family/c.opt +++ b/gcc/c-family/c.opt @@ -684,6 +684,12 @@ C ObjC C++ LTO ObjC++ Warning Alias(Wformat-overflow=, 1, 0) IntegerRange(0, 2) Warn about function calls with format strings that write past the end of the destination region. Same as -Wformat-overflow=1. +Wformat-int-precision +C ObjC C++ ObjC++ Var(warn_format_int_precision) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=,warn_format >= 1, 0) +Warn when passing an argument of an incompatible integer type to a 'd', 'i', +'b', 'B', 'o', 'u', 'x', or 'X' conversion specifier even when it has the same +precision as the expected type. + Wformat-security C ObjC C++ ObjC++ Var(warn_format_security) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 2, 0) Warn about possible security problems with format functions. diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 3bddfbaae6a..94a7ad96c50 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -351,7 +351,7 @@ Objective-C and Objective-C++ Dialects}. -Werror -Werror=* -Wexpansion-to-defined -Wfatal-errors @gol -Wfloat-conversion -Wfloat-equal -Wformat -Wformat=2 @gol -Wno-format-contains-nul -Wno-format-extra-args @gol --Wformat-nonliteral -Wformat-overflow=@var{n} @gol +-Wformat-nonliteral -Wformat-overflow=@var{n} -Wformat-int-precision @gol -Wformat-security -Wformat-signedness -Wformat-truncation=@var{n} @gol -Wformat-y2k -Wframe-address @gol -Wframe-larger-than=@var{byte-size} -Wno-free-nonheap-object @gol @@ -6122,6 +6122,21 @@ If @option{-Wformat} is specified, also warn if the format string is not a string literal and so cannot be checked, unless the format function takes its format arguments as a @code{va_list}. +@item -Wformat-int-precision +@opindex Wformat-int-precision +@opindex Wno-format-int-precision +Warn when passing an argument of an incompatible integer type to +a @samp{d}, @samp{i}, @samp{b}, @samp{B}, @samp{o}, @samp{u}, @samp{x}, +or @samp{X} conversion specifier even when it has the same precision as +the expected type. For example, on targets where @code{int64_t} is a typedef +for @code{long}, the warning is issued for the @code{printf} call below even +when both @code{long} and @code{long long} have the same size and precision. + +@smallexample + extern int64_t n; + printf ("%lli", n); +@end smallexample + @item -Wformat-security @opindex Wformat-security @opindex Wno-format-security diff --git a/gcc/testsuite/c-c++-common/Wformat-int-precision-1.c b/gcc/testsuite/c-c++-common/Wformat-int-precision-1.c new file mode 100644 index 00000000000..a06e047c933 --- /dev/null +++ b/gcc/testsuite/c-c++-common/Wformat-int-precision-1.c @@ -0,0 +1,7 @@ +/* { dg-do compile { target { ! long_neq_int } } } */ +/* { dg-options "-Wformat" } */ + +void test () +{ + __builtin_printf ("%d\n", (long) 1); /* { dg-warning "expects argument of type" } */ +} diff --git a/gcc/testsuite/c-c++-common/Wformat-int-precision-2.c b/gcc/testsuite/c-c++-common/Wformat-int-precision-2.c new file mode 100644 index 00000000000..e9b41b4f42e --- /dev/null +++ b/gcc/testsuite/c-c++-common/Wformat-int-precision-2.c @@ -0,0 +1,8 @@ +/* { dg-do compile { target { ! long_neq_int } } } */ +/* { dg-options "-Wformat -Wno-format-int-precision" } */ + +void test () +{ + __builtin_printf ("%d\n", (long) 1); /* { dg-bogus "expects argument of type" } */ + __builtin_printf ("%d\n", (long long) 1); /* { dg-warning "expects argument of type" "" { target int32 } } */ +}