From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1791) id 204CB385782B; Thu, 9 Feb 2023 19:48:29 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 204CB385782B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1675972109; bh=hQMLZIVil/R3cz/Mk9uA62gstWFHDbRSvLC0ADt6tzQ=; h=From:To:Subject:Date:From; b=Z/ns5v9Xd0JYKjRj6h07WsfHa08N/o9Mr6sPETBnTloW8/iO5tOuAoMQekxEPWK66 p8D6twh5TNhCsVtbln0my9+6CTHwplmzY6vCEf23IQUPdjxuD3005q22t71EJPIyyO oiJTDL6Za4g23s5fDOzchSagzxVBJOT4CqO36wyc= 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] string: Use asm alias instead of symbol redirections for stpcpy and mempcpy X-Act-Checkin: glibc X-Git-Author: Adhemerval Zanella X-Git-Refname: refs/heads/azanella/clang X-Git-Oldrev: 7e5a4ee294e03f42bc3ce1f460f74e7a049a9fa2 X-Git-Newrev: 265a0626b9e73970497e050f184fa5804451cacf Message-Id: <20230209194829.204CB385782B@sourceware.org> Date: Thu, 9 Feb 2023 19:48:29 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=265a0626b9e73970497e050f184fa5804451cacf commit 265a0626b9e73970497e050f184fa5804451cacf Author: Adhemerval Zanella Date: Tue Mar 15 08:41:43 2022 -0300 string: Use asm alias instead of symbol redirections for stpcpy and mempcpy Commit 939da411433 added symbols redirections to handle ISO C namespace, however some compiler does not support to redeclare the function prototype. Moving these defintions to exported header it not a good practice (it exposes a internal implementation and it would require to add macros to define it only internally). Instead this patch replaces the symbol redirections by direct asm aliases, as done to handle libcall generation done by compiler on some loop optimizations. The only issue is sparc binutils generates an extra __mempcpy plt not called anywhere in the code, which indicates a binutils issue (this is added in the localplt.data for now). Checked on most of affected ABIs. Diff: --- include/string.h | 4 ++-- sysdeps/unix/sysv/linux/sparc/sparc64/localplt.data | 3 +++ 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/include/string.h b/include/string.h index a9120ff37c..d6e352e214 100644 --- a/include/string.h +++ b/include/string.h @@ -178,8 +178,8 @@ extern __typeof (strsep) strsep attribute_hidden; && !defined NO_MEMPCPY_STPCPY_REDIRECT /* Redirect calls to __builtin_mempcpy and __builtin_stpcpy to call __mempcpy and __stpcpy if not inlined. */ -extern __typeof (mempcpy) mempcpy __asm__ ("__mempcpy"); -extern __typeof (stpcpy) stpcpy __asm__ ("__stpcpy"); +__asm__ ("mempcpy = __mempcpy"); +__asm__ ("stpcpy = __stpcpy"); #endif extern void *__memcpy_chk (void *__restrict __dest, diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/localplt.data b/sysdeps/unix/sysv/linux/sparc/sparc64/localplt.data index 15c0f8ccf7..e7ab61dcbe 100644 --- a/sysdeps/unix/sysv/linux/sparc/sparc64/localplt.data +++ b/sysdeps/unix/sysv/linux/sparc/sparc64/localplt.data @@ -17,4 +17,7 @@ libc.so: calloc libc.so: free libc.so: malloc libc.so: realloc +# Unreferenced PLT created by the symbols aliases used to redirect +# the compiler generated mempcpy/stpcyp calls done by builtin usage. +libc.so: __mempcpy libm.so: matherr