From patchwork Mon Feb 26 21:53:18 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Myers X-Patchwork-Id: 26097 Received: (qmail 108554 invoked by alias); 26 Feb 2018 21:53:26 -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 108541 invoked by uid 89); 26 Feb 2018 21:53:25 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-24.5 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RCVD_IN_DNSWL_NONE, SPF_PASS, URIBL_RED autolearn=ham version=3.3.2 spammy= X-HELO: relay1.mentorg.com Date: Mon, 26 Feb 2018 21:53:18 +0000 From: Joseph Myers To: Subject: Fix two more -Os strcoll / wcscoll build failures Message-ID: User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 X-ClientProxiedBy: svr-ies-mbx-02.mgc.mentorg.com (139.181.222.2) To SVR-IES-MBX-03.mgc.mentorg.com (139.181.222.3) Continuing fixes for -Os build issues shown with build-many-glibcs.py, this patch adds uses of DIAG_* to disable -Wmaybe-uninitialized in two more places where code inlined from strcoll / wcscoll is wrongly diagnosed as possibly using uninitialized structure fields. (All these warnings in different places for these functions are I think essentially the same bug.) Tested with build-many-glibcs.py for alpha-linux-gnu and mips-linux-gnu that this fixes the -Os build failures for those configurations with GCC 7. 2018-02-26 Joseph Myers * locale/weightwc.h (findidx): Ignore -Wmaybe-uninitialized for -Os in two more places. Reviewed-by: Adhemerval Zanella diff --git a/locale/weightwc.h b/locale/weightwc.h index ac25ba9..36c65b5 100644 --- a/locale/weightwc.h +++ b/locale/weightwc.h @@ -28,7 +28,15 @@ findidx (const int32_t *table, const wint_t *extra, const wint_t **cpp, size_t len) { + /* With GCC 7 when compiling with -Os the compiler warns that + seq1.back_us and seq2.back_us, which become *cpp, might be used + uninitialized. This is impossible as this function cannot be + called except in cases where those fields have been + initialized. */ + DIAG_PUSH_NEEDS_COMMENT; + DIAG_IGNORE_Os_NEEDS_COMMENT (7, "-Wmaybe-uninitialized"); wint_t ch = *(*cpp)++; + DIAG_POP_NEEDS_COMMENT; int32_t i = __collidx_table_lookup ((const char *) table, ch); if (i >= 0) @@ -107,11 +115,18 @@ findidx (const int32_t *table, continue; } + /* With GCC 7 when compiling with -Os the compiler warns + that seq1.back_us and seq2.back_us, which become usrc, + might be used uninitialized. This is impossible for the + same reason as described above. */ + DIAG_PUSH_NEEDS_COMMENT; + DIAG_IGNORE_Os_NEEDS_COMMENT (7, "-Wmaybe-uninitialized"); if (cp[nhere - 1] > usrc[nhere -1]) { cp += 2 * nhere; continue; } + DIAG_POP_NEEDS_COMMENT; if (cp[2 * nhere - 1] < usrc[nhere -1]) {