From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1791) id 446623858410; Thu, 21 Dec 2023 18:53:15 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 446623858410 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1703184795; bh=Cfl7Oxwt/ebUinjcU06HSqbc8PPre1CcqEQDupdHZMA=; h=From:To:Subject:Date:From; b=qyz8Hx7q/ElgkcNx7gePWAF3Vgf+dwUaTgCUQE10xNXSvQD7L1LEB5RDf5fXT/GW7 gQ96j5ihHxzpkiGClzUKSr751Cz28I4JIqphIJLwmDdiOhGKoXyj/kNaJY9PKVyQk5 x+iHAwlq+07/ZGAG947XFKBEMHGo4/AZKt4k0pbo= 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: 10d309753bd56690dbdb1eddea604e50b084c244 X-Git-Newrev: e48d42817486f2a755bc87981a10da5b6b0783a6 Message-Id: <20231221185315.446623858410@sourceware.org> Date: Thu, 21 Dec 2023 18:53:15 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=e48d42817486f2a755bc87981a10da5b6b0783a6 commit e48d42817486f2a755bc87981a10da5b6b0783a6 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 86d1fa4abe..27f4e6e563 100644 --- a/include/string.h +++ b/include/string.h @@ -179,8 +179,8 @@ 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