From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from esa4.mentor.iphmx.com (esa4.mentor.iphmx.com [68.232.137.252]) by sourceware.org (Postfix) with ESMTPS id B715638418B2 for ; Wed, 29 Jun 2022 20:44:20 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org B715638418B2 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=codesourcery.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=mentor.com X-IronPort-AV: E=Sophos;i="5.92,232,1650960000"; d="scan'208";a="78054481" Received: from orw-gwy-02-in.mentorg.com ([192.94.38.167]) by esa4.mentor.iphmx.com with ESMTP; 29 Jun 2022 12:44:16 -0800 IronPort-SDR: FU7cKubu9eTvwkl+G9JS2rEVo4n75bXO4ghtHhC54QMNW9jtPZv3l+EoxyKkBEvgpq5XJwv/v8 7YvGBQ7VAy/q3fmiV9187bF8zgX56HudDqwzG7wFncBHCymo6MK56sKX/Vo9+kjVK6i5uTnUqb RJmTNB0l3uuPhUcYA3tDB6xBswnEBg41YooyWnKQHkdKoWIUCq0VNEV5RftPfNOkYoDyJXNy2L WajQ0QJ/48InsjdO52zLJR5fMTUDUW0T1dO6yqWU8iBdrXqWyweSauDh+W7Wmja9Onou1iy0kF OW0= Date: Wed, 29 Jun 2022 20:44:10 +0000 From: Joseph Myers X-X-Sender: jsm28@digraph.polyomino.org.uk To: Subject: lto: Fix option merging [PR106129] Message-ID: User-Agent: Alpine 2.22 (DEB 394 2020-01-19) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-Originating-IP: [137.202.0.90] X-ClientProxiedBy: svr-ies-mbx-09.mgc.mentorg.com (139.181.222.9) To svr-ies-mbx-10.mgc.mentorg.com (139.181.222.10) X-Spam-Status: No, score=-3118.6 required=5.0 tests=BAYES_00, GIT_PATCH_0, HEADER_FROM_DIFFERENT_DOMAINS, KAM_DMARC_STATUS, SPF_HELO_PASS, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) 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-List-Received-Date: Wed, 29 Jun 2022 20:44:22 -0000 The LTO merging of options from different input files was broken by: commit 227a2ecf663d69972b851f51f1934d18927b62cd Author: Martin Liska Date: Fri Mar 12 11:53:47 2021 +0100 lto-wrapper: Use vec data type. Previously, find_and_merge_options would merge options it read into those in *opts. After this commit, options in *opts on entry to find_and_merge_options are ignored; the only merging that takes place is between multiple sets of options in the same input file that are read in the same call to this function (not sure how that case can occur at all). The effects include, for example, that if some objects are built with PIC enabled and others with it disabled, and the last LTO object processed has PIC enabled, the choice of PIC for the last object will result in the whole program being built as PIC, when the merging logic is intended to ensure that a mixture of PIC and non-PIC objects results in the whole program being built as non-PIC. Fix this with an extra argument to find_and_merge_options to determine whether merging should take place. This shows up a second issue with that commit (which I think wasn't actually intended to change code semantics at all): once merging is enabled again, the check for -Xassembler options became an infinite loop in the case where both inputs had -Xassembler options, with the same first option, so fix that loop to restore the previous semantics. Note that I'm not sure how LTO option merging might be tested in the testsuite (clearly there wasn't sufficient, if any, coverage to detect these bugs). Bootstrapped with no regressions for x86_64-pc-linux-gnu. OK to commit? PR lto/106129 * lto-wrapper.cc (find_option): Add argument start. (merge_and_complain): Loop over existing_opt_index and existing_opt2_index for Xassembler check. Update calls to find_option. (find_and_merge_options): Add argument first to determine whether to merge options with those passed in *opts. (run_gcc): Update calls to find_and_merge_options. diff --git a/gcc/lto-wrapper.cc b/gcc/lto-wrapper.cc index 26e06e7..795ab74 100644 --- a/gcc/lto-wrapper.cc +++ b/gcc/lto-wrapper.cc @@ -170,13 +170,14 @@ get_options_from_collect_gcc_options (const char *collect_gcc, return decoded; } -/* Find option in OPTIONS based on OPT_INDEX. -1 value is returned - if the option is not present. */ +/* Find option in OPTIONS based on OPT_INDEX, starting at START. -1 + value is returned if the option is not present. */ static int -find_option (vec &options, size_t opt_index) +find_option (vec &options, size_t opt_index, + unsigned start = 0) { - for (unsigned i = 0; i < options.length (); ++i) + for (unsigned i = start; i < options.length (); ++i) if (options[i].opt_index == opt_index) return i; @@ -575,13 +576,16 @@ merge_and_complain (vec &decoded_options, else j++; + int existing_opt_index, existing_opt2_index; if (!xassembler_options_error) - for (i = j = 0; ; i++, j++) + for (existing_opt_index = existing_opt2_index = 0; ; + existing_opt_index++, existing_opt2_index++) { - int existing_opt_index - = find_option (decoded_options, OPT_Xassembler); - int existing_opt2_index - = find_option (fdecoded_options, OPT_Xassembler); + existing_opt_index + = find_option (decoded_options, OPT_Xassembler, existing_opt_index); + existing_opt2_index + = find_option (fdecoded_options, OPT_Xassembler, + existing_opt2_index); cl_decoded_option *existing_opt = NULL; cl_decoded_option *existing_opt2 = NULL; @@ -1100,7 +1104,7 @@ find_crtoffloadtable (int save_temps, const char *dumppfx) static bool find_and_merge_options (int fd, off_t file_offset, const char *prefix, - vec decoded_cl_options, + vec decoded_cl_options, bool first, vec *opts, const char *collect_gcc) { off_t offset, length; @@ -1110,6 +1114,9 @@ find_and_merge_options (int fd, off_t file_offset, const char *prefix, int err; vec fdecoded_options; + if (!first) + fdecoded_options = *opts; + simple_object_read *sobj; sobj = simple_object_start_read (fd, file_offset, "__GNU_LTO", &errmsg, &err); @@ -1130,7 +1137,6 @@ find_and_merge_options (int fd, off_t file_offset, const char *prefix, data = (char *)xmalloc (length); read (fd, data, length); fopts = data; - bool first = true; do { vec f2decoded_options @@ -1417,8 +1423,10 @@ run_gcc (unsigned argc, char *argv[]) int auto_parallel = 0; bool no_partition = false; const char *jobserver_error = NULL; + bool fdecoded_options_first = true; vec fdecoded_options; fdecoded_options.create (16); + bool offload_fdecoded_options_first = true; vec offload_fdecoded_options = vNULL; struct obstack argv_obstack; int new_head_argc; @@ -1510,11 +1518,13 @@ run_gcc (unsigned argc, char *argv[]) } if (find_and_merge_options (fd, file_offset, LTO_SECTION_NAME_PREFIX, - decoded_options, &fdecoded_options, + decoded_options, fdecoded_options_first, + &fdecoded_options, collect_gcc)) { have_lto = true; ltoobj_argv[ltoobj_argc++] = argv[i]; + fdecoded_options_first = false; } close (fd); } @@ -1773,9 +1783,12 @@ cont1: fatal_error (input_location, "cannot open %s: %m", filename); if (!find_and_merge_options (fd, file_offset, OFFLOAD_SECTION_NAME_PREFIX, - decoded_options, &offload_fdecoded_options, + decoded_options, + offload_fdecoded_options_first, + &offload_fdecoded_options, collect_gcc)) fatal_error (input_location, "cannot read %s: %m", filename); + offload_fdecoded_options_first = false; close (fd); if (filename != offload_argv[i]) XDELETEVEC (filename); -- Joseph S. Myers joseph@codesourcery.com