From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1791) id 757923858407; Wed, 30 Aug 2023 12:42:13 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 757923858407 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1693399333; bh=l18RT7VCFDDyJmb26vOFUdX599DZ4PeGlH70V4eh2hE=; h=From:To:Subject:Date:From; b=kTLtctJXS5V3ChN+W8e6ynB5/OSqkXYF7uEUF8PJgZdV3yBsH3AKyn/Eu06/J+RPm 5yXHq6c/RCwOK/K9gHzM56zpF9m7IJegIXWDtcE67jS9iZNRf9uESO4TkYFHRr5p2K QRvByUB5JuO25EM8PZWW5ccfevgzvuCOXX7I1leg= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Adhemerval Zanella To: glibc-cvs@sourceware.org Subject: [glibc/azanella/clang] elf: Use volatile to set __rseq_size and __rseq_offset X-Act-Checkin: glibc X-Git-Author: Adhemerval Zanella X-Git-Refname: refs/heads/azanella/clang X-Git-Oldrev: 37dc8420028936691d68039c5b5389fba9ed2a56 X-Git-Newrev: 262706b313386a963a7ec5afd3bab550add73732 Message-Id: <20230830124213.757923858407@sourceware.org> Date: Wed, 30 Aug 2023 12:42:13 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=262706b313386a963a7ec5afd3bab550add73732 commit 262706b313386a963a7ec5afd3bab550add73732 Author: Adhemerval Zanella Date: Sun Apr 3 11:23:20 2022 -0300 elf: Use volatile to set __rseq_size and __rseq_offset To avoid compiler to optimize them away. Diff: --- sysdeps/nptl/dl-tls_init_tp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/sysdeps/nptl/dl-tls_init_tp.c b/sysdeps/nptl/dl-tls_init_tp.c index 2ed98c5a31..dfd8591575 100644 --- a/sysdeps/nptl/dl-tls_init_tp.c +++ b/sysdeps/nptl/dl-tls_init_tp.c @@ -107,7 +107,7 @@ __tls_init_tp (void) { /* We need a writable view of the variables. They are in .data.relro and are not yet write-protected. */ - extern unsigned int size __asm__ ("__rseq_size"); + extern volatile unsigned int size __asm__ ("__rseq_size"); size = sizeof (pd->rseq_area); } @@ -117,7 +117,7 @@ __tls_init_tp (void) all targets support __thread_pointer, so set __rseq_offset only if the rseq registration may have happened because RSEQ_SIG is defined. */ - extern ptrdiff_t offset __asm__ ("__rseq_offset"); + extern volatile ptrdiff_t offset __asm__ ("__rseq_offset"); offset = (char *) &pd->rseq_area - (char *) __thread_pointer (); #endif }