From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=5.0 tests=DKIM_INVALID,DKIM_SIGNED, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL autolearn=ham autolearn_force=no version=3.4.2 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by inbox.vuxu.org (OpenSMTPD) with SMTP id 848cb6ca for ; Mon, 3 Feb 2020 20:44:32 +0000 (UTC) Received: (qmail 26156 invoked by uid 550); 3 Feb 2020 20:44:31 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Reply-To: musl@lists.openwall.com Received: (qmail 26124 invoked from network); 3 Feb 2020 20:44:30 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1580762658; bh=yIhfeXIuxEUHQqewaeXkr74DPaitA2YHlGnzrt64NDs=; h=X-UI-Sender-Class:Date:From:To:Subject; b=Xctd/fJZLpu8YFDslpt/f0Xk/rICBD41CksM7j514AXXwomiVRZCgRzFfUd9F12WZ gy1AI1fRxrJD7ZfwwrY6Yrpf82rw8G8KVNt6/2JyUPgoQVhuUK8SManMjh6yE1ZPKB pBCo4hwbuwg0KqUNUhHs39T5YoVeV/rY92GxGWzU= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Date: Mon, 3 Feb 2020 21:44:17 +0100 From: Sebastian Kemper To: musl@lists.openwall.com Message-ID: <20200203204416.GA19036@darth.lan> Mail-Followup-To: musl@lists.openwall.com MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Provags-ID: V03:K1:KdWCttOno/ssNbBT5PRFKtaGtqIB/igl0DC1rPIKyNJy/eyDJEm PRZDMZp94ZezWrSoa8vwsh3sd30XGLJQr7aHH6jIhVVcjcw2vK5tH6pczFce5B3XoOBDuIP Viuo8zkfL1uyLv98eSJjrszHNJST8mLUVquNUGjTtiM9J8pnHOPvmnRcsnt8r+w3CSxoN+B cHXOQSw6LXUqOLyybK74A== X-UI-Out-Filterresults: notjunk:1;V03:K0:rmEblUhBqAk=:yTESIzMar2NDPRGOUNQj4N CmJ+ydA5d8dXOwCCwgIrimQX94WTl6mCP3cmhkY1/c23pWryZfb0ojVXoiT+iulJ7cVk1/wDq T3d0WJOG4JNx9X9JMDlLyiJkp+rGR5i70HDamgara5lVHIVQdqVDk3sAiTGuMowvZVX82HJkW tcBpjJHkzLAw4N2WqcQKgzxNsRdfiRff8k/ErQGTmEHRzZiF+8uIP6mZwRbI3/irnWwyO9v7e E3xGvj/Cfo//4sFyFAbL/Smy6g3e9EVruBgdAb2zkgpA/pDY2uO623uuKD0E68Ded9i2vh6pv im9PGscJtKQU6SOSL0Y8928cvLVccAlPCvZjnLzC/FeFdMsffqhft9d9O/SaDzbx89kfklP/F eR6dCLfiplD3YzI4DFAlYGTpymCGEmKguCZUKRWWhtb8C6qPqzZgC/WZPgti7/YLTN8szTIoy DSjBB0sAZjsT92ga1dQfWP77gpS7A9ZXQyurvasBSvfGtSEyM09Uex0imah0pCbYi0KRNLMBm YbtriRnPCvaRYWC2V0LbG2Qu8QyvQdtL3dfJKx+5wXkz3gmVpjt9VNheIwa/MSf9Cp7RAzsft efh1TkkMomQqwr3DCZ85Ii4yxIiBDRAV7XUhEYrS18ZpDe3w7qkGrwOxbDj1TbPV7ARjAWADQ nbL+XOZiCTvrLso0PZokghenxqzTtUBHT88phI58Pnh4psziMIiaK4c4ccCwnjPAsXaHrTrSA OXq10qU2sobdfkZp4n5TJ3xSeatJxedy7E979VBdlCzJj9Pr3LOJjfvZ1MbfPG6+LARiPxTsG E+uMWo071jKk1Xq5InjF9tfZQmv9pYA8OXau/LTt4tYfeXw9yMkIsXdd3X0H2ign1g954/5MJ pa0uyThSxewLF5uSg/HfMEm+oescL6bcZOQZ/+4t0qQk303EeEoQL0oNRg0uUYuVu9WS1GGD/ g7uSp+aREWmQ/LRPaXfbGjA24mNPULbGKvex/x0Vjl+X/3GvKxNmPkRf6IKMcFHG3Zktthn9r PM534h2BzNuku044IFznfc1hrxbgEkic6DJnZK8298WAav2+P2QwtLzOJ/OIYtNjgIZQeaqLh e20abab4fQbM9KfjBlCl1ZmYSoudRaL5BwzFDjb1YhGvg+ZKRTQIMXqgx6P+3OnCwW+AWvV6L sutidSsVJEkHkU8/gs/9T8Dbu3th+XnRSG8DWH1WFlaz20wk3day8kHfg+z/BLdBGrkqlkmn0 6iG56csttFYcUE1r8 Subject: [musl] Cross-compiling and -D_LARGEFILE64_SOURCE Hello list, I'm working on updating apr in OpenWrt. During configure it uses TRY_RUN a lot, so we have a lot of configure variables defined to point it into the right direction. With one variable I have some trouble: apr_cv_use_lfs64=yes. The trouble is I don't know whether or not to set it. It basically forces -D_LARGEFILE64_SOURCE to be included in the CPPFLAGS. So my first impulse was to force it to "yes". But then I saw some build logs from Alpine Linux: https://build.alpinelinux.org/buildlogs/build-edge-x86/main/apr/apr-1.7.0-r0.log checking whether the compiler provides atomic builtins... yes checking whether to enable -D_LARGEFILE64_SOURCE... no configure: Configured for Linux 4.14 So Alpine is not cross-compiling here, and the result is "no". And this particular log is for i586 (I thought - before seeing this log - that maybe -D_LARGEFILE64_SOURCE is needed for non-64-bit platforms). The TRY_RUN that apr uses to find out whether to add -D_LARGEFILE64_SOURCE is pasted at the bottom of this mail. If I run configure on my x86_64 glibc laptop it says "no". In the Alpine logs it also says "no". If I search the Internet I find some old pastes where the outcome was "yes", though. It kind of looks like the answer over time changed from "yes" to "no", for no apparent reason (at least for me). If it sets -D_LARGEFILE64_SOURCE it propagates the same flag to its users via apr-1-config. In the apr sources I see the define also being used occasionally. include/arch/unix/apr_arch_file_io.h: #if APR_HAS_LARGE_FILES && defined(_LARGEFILE64_SOURCE) #define stat(f,b) stat64(f,b) #define lstat(f,b) lstat64(f,b) #define fstat(f,b) fstat64(f,b) #define lseek(f,o,w) lseek64(f,o,w) #define ftruncate(f,l) ftruncate64(f,l) typedef struct stat64 struct_stat; #else typedef struct stat struct_stat; #endif file_io/unix/open.c: #if APR_HAS_LARGE_FILES && defined(_LARGEFILE64_SOURCE) oflags |= O_LARGEFILE; #elif defined(O_LARGEFILE) if (flag & APR_FOPEN_LARGEFILE) { oflags |= O_LARGEFILE; } #endif I obviously would like LFS support, but I don't know about this configure variable. I guess the correct answer must be one of these: "Don't use it" "Use it" "Use it if condition X applies" I guess this is a bit off-topic maybe. But I'm really running out of ideas :) So if anybody can share some insight I'd really appreciate it. Kind regards, Seb AC_CACHE_CHECK([whether to enable -D_LARGEFILE64_SOURCE], [apr_cv_use_lfs64], [ apr_save_CPPFLAGS=$CPPFLAGS CPPFLAGS="$CPPFLAGS -D_LARGEFILE64_SOURCE" AC_TRY_RUN([ #include #include #include #include #include #include void main(void) { int fd, ret = 0; struct stat64 st; off64_t off = 4242; if (sizeof(off64_t) != 8 || sizeof(off_t) != 4) exit(1); if ((fd = open("conftest.lfs", O_LARGEFILE|O_CREAT|O_WRONLY, 0644)) < 0) exit(2); if (ftruncate64(fd, off) != 0) ret = 3; else if (fstat64(fd, &st) != 0 || st.st_size != off) ret = 4; else if (lseek64(fd, off, SEEK_SET) != off) ret = 5; else if (close(fd) != 0) ret = 6; else if (lstat64("conftest.lfs", &st) != 0 || st.st_size != off) ret = 7; else if (stat64("conftest.lfs", &st) != 0 || st.st_size != off) ret = 8; unlink("conftest.lfs"); exit(ret); }], [apr_cv_use_lfs64=yes], [apr_cv_use_lfs64=no], [apr_cv_use_lfs64=no]) CPPFLAGS=$apr_save_CPPFLAGS]) if test "$apr_cv_use_lfs64" = "yes"; then APR_ADDTO(CPPFLAGS, [-D_LARGEFILE64_SOURCE]) fi