From patchwork Tue Nov 14 17:53:14 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Myers X-Patchwork-Id: 24241 Received: (qmail 121349 invoked by alias); 14 Nov 2017 17:53:22 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 121338 invoked by uid 89); 14 Nov 2017 17:53:21 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-24.3 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KB_WAM_FROM_NAME_SINGLEWORD, RCVD_IN_DNSWL_NONE, SPF_PASS, URIBL_RED autolearn=ham version=3.3.2 spammy= X-HELO: relay1.mentorg.com Date: Tue, 14 Nov 2017 17:53:14 +0000 From: Joseph Myers To: CC: Subject: Fix string/tester.c build with GCC 8 [committed] Message-ID: User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 X-ClientProxiedBy: svr-ies-mbx-01.mgc.mentorg.com (139.181.222.1) To SVR-IES-MBX-03.mgc.mentorg.com (139.181.222.3) GCC 8 warns about more cases of string functions truncating their output or not copying a trailing NUL byte. This patch fixes testsuite build failures caused by such warnings in string/tester.c. In general, the warnings are disabled around the relevant calls using DIAG_* macros, since the relevant cases are being deliberately tested. In one case, the warning is with -Wstringop-overflow= instead of -Wstringop-truncation; in that case, the conditional is __GNUC_PREREQ (7, 0) (being the version where -Wstringop-overflow= was introduced), to allow the conditional to be removed sooner, since it's harmless to disable the warning for a GCC version where it doesn't actually occur. In the case of warnings for strncpy calls in test_memcmp, the calls in question are changed to use memcpy, as they don't copy a trailing NUL and the point of that code is to test memcmp rather than strncpy. Tested (compilation) with GCC 8 for x86_64-linux-gnu with build-many-glibcs.py (in conjunction with Martin's patch to allow glibc to build). Committed. 2017-11-14 Joseph Myers * string/tester.c (test_stpncpy): Disable -Wstringop-truncation for stpncpy calls for GCC 8. (test_strncat): Disable -Wstringop-truncation warning for strncat calls for GCC 8. Disable -Wstringop-overflow= warning for one strncat call for GCC 7. (test_strncpy): Disable -Wstringop-truncation warning for strncpy calls for GCC 8. (test_memcmp): Use memcpy instead of strncpy for calls not copying trailing NUL. diff --git a/string/tester.c b/string/tester.c index 4b928b4..66b1151 100644 --- a/string/tester.c +++ b/string/tester.c @@ -264,8 +264,15 @@ test_stpncpy (void) { it = "stpncpy"; memset (one, 'x', sizeof (one)); + DIAG_PUSH_NEEDS_COMMENT; +#if __GNUC_PREREQ (8, 0) + /* GCC 8 warns about stpncpy truncating output; this is deliberately + tested here. */ + DIAG_IGNORE_NEEDS_COMMENT (8, "-Wstringop-truncation"); +#endif check (stpncpy (one, "abc", 2) == one + 2, 1); check (stpncpy (one, "abc", 3) == one + 3, 2); + DIAG_POP_NEEDS_COMMENT; check (stpncpy (one, "abc", 4) == one + 3, 3); check (one[3] == '\0' && one[4] == 'x', 4); check (stpncpy (one, "abcd", 5) == one + 4, 5); @@ -420,13 +427,27 @@ test_strncat (void) equal (one, "cd", 9); (void) strcpy (one, "ab"); + DIAG_PUSH_NEEDS_COMMENT; +#if __GNUC_PREREQ (8, 0) + /* GCC 8 warns about strncat truncating output; this is deliberately + tested here. */ + DIAG_IGNORE_NEEDS_COMMENT (8, "-Wstringop-truncation"); +#endif (void) strncat (one, "cdef", 2); + DIAG_POP_NEEDS_COMMENT; equal (one, "abcd", 10); /* Count-limited. */ (void) strncat (one, "gh", 0); equal (one, "abcd", 11); /* Zero count. */ + DIAG_PUSH_NEEDS_COMMENT; +#if __GNUC_PREREQ (7, 0) + /* GCC 8 warns about strncat bound equal to source length; this is + deliberately tested here. */ + DIAG_IGNORE_NEEDS_COMMENT (8, "-Wstringop-overflow="); +#endif (void) strncat (one, "gh", 2); + DIAG_POP_NEEDS_COMMENT; equal (one, "abcdgh", 12); /* Count and length equal. */ DIAG_PUSH_NEEDS_COMMENT; @@ -523,11 +544,25 @@ test_strncpy (void) equal (one, "abc", 2); /* Did the copy go right? */ (void) strcpy (one, "abcdefgh"); + DIAG_PUSH_NEEDS_COMMENT; +#if __GNUC_PREREQ (8, 0) + /* GCC 8 warns about strncpy truncating output; this is deliberately + tested here. */ + DIAG_IGNORE_NEEDS_COMMENT (8, "-Wstringop-truncation"); +#endif (void) strncpy (one, "xyz", 2); + DIAG_POP_NEEDS_COMMENT; equal (one, "xycdefgh", 3); /* Copy cut by count. */ (void) strcpy (one, "abcdefgh"); + DIAG_PUSH_NEEDS_COMMENT; +#if __GNUC_PREREQ (8, 0) + /* GCC 8 warns about strncpy truncating output; this is deliberately + tested here. */ + DIAG_IGNORE_NEEDS_COMMENT (8, "-Wstringop-truncation"); +#endif (void) strncpy (one, "xyz", 3); /* Copy cut just before NUL. */ + DIAG_POP_NEEDS_COMMENT; equal (one, "xyzdefgh", 4); (void) strcpy (one, "abcdefgh"); @@ -542,7 +577,14 @@ test_strncpy (void) equal (one+5, "fgh", 9); (void) strcpy (one, "abc"); + DIAG_PUSH_NEEDS_COMMENT; +#if __GNUC_PREREQ (8, 0) + /* GCC 8 warns about strncpy truncating output; this is deliberately + tested here. */ + DIAG_IGNORE_NEEDS_COMMENT (8, "-Wstringop-truncation"); +#endif (void) strncpy (one, "xyz", 0); /* Zero-length copy. */ + DIAG_POP_NEEDS_COMMENT; equal (one, "abc", 10); (void) strncpy (one, "", 2); /* Zero-length source. */ @@ -1151,8 +1193,8 @@ test_memcmp (void) { char *a = one + i; char *b = two + i; - strncpy(a, "--------11112222", 16); - strncpy(b, "--------33334444", 16); + memcpy(a, "--------11112222", 16); + memcpy(b, "--------33334444", 16); check(memcmp(b, a, 16) > 0, cnt++); check(memcmp(a, b, 16) < 0, cnt++); }