From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/4650 Path: news.gmane.org!not-for-mail From: Szabolcs Nagy Newsgroups: gmane.linux.lib.musl.general Subject: Re: Static linking of musl with code compiled using GNU header files Date: Fri, 14 Mar 2014 17:29:57 +0100 Message-ID: <20140314162957.GB27448@port70.net> References: <53232493.80901@gcom.com> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1394814600 4044 80.91.229.3 (14 Mar 2014 16:30:00 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 14 Mar 2014 16:30:00 +0000 (UTC) Cc: Support at Gcom To: musl@lists.openwall.com Original-X-From: musl-return-4654-gllmg-musl=m.gmane.org@lists.openwall.com Fri Mar 14 17:30:10 2014 Return-path: Envelope-to: gllmg-musl@plane.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by plane.gmane.org with smtp (Exim 4.69) (envelope-from ) id 1WOUzp-0002yt-PP for gllmg-musl@plane.gmane.org; Fri, 14 Mar 2014 17:30:09 +0100 Original-Received: (qmail 15559 invoked by uid 550); 14 Mar 2014 16:30:09 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Original-Received: (qmail 15551 invoked from network); 14 Mar 2014 16:30:09 -0000 Content-Disposition: inline In-Reply-To: <53232493.80901@gcom.com> User-Agent: Mutt/1.5.21 (2010-09-15) Xref: news.gmane.org gmane.linux.lib.musl.general:4650 Archived-At: * David Grothe [2014-03-14 10:47:31 -0500]: > I have a very large code base that I have been compiling on Linux > using the standard GNU C compiler [gcc (Ubuntu/Linaro > 4.6.3-1ubuntu5) 4.6.3]. I have been using shared object libraries, > but for reasons of software support I would now like to link all my > commands (a couple of dozen) and daemons using static libraries so > that the code files are self-contained and can be copied, along with > a core file, to any server back in my shop for analysis. With > dynamic libraries I have to have exactly the same version of libc > installed on the machine that I use to examine the core file as were > present on the machine that generated the core file, or else gdb > will not produce a stack back trace with file and line number > information. So much for the background. > > I really don't want to port my code base to using the musl header > files. I want to keep compiling with the GNU headers. When I do compiling with the gnu headers is broken and it depends on the cflags used > this and link my-huge-program.o with musl libc.a I get the following > list of unresolved externals: > > U __divdi3 comes from libgcc.a, if it's missing you have a toolchain issue > w __fini_array_end > w __fini_array_start i think musl supports init/fini arrays (see src/exit/exit.c) > U __moddi3 libgcc > U __sysv_signal you may want to replace it with signal > U __udivdi3 > U __umoddi3 libgcc > U __vfprintf_chk > U __vsnprintf_chk > U __vsprintf_chk there are many _chk functions for _FORTIFY_SOURCE, musl may provide these eventually, until then you can add your own chk.o with dummy implementations (possibly with the safety checks i omit here): int __vfprintf_chk(FILE *f, int flag, const char *fmt, va_list ap) { return vfprintf(f, fmt, ap); } int __vsnprintf_chk(char *s, size_t n, int flag, size_t size, const char *fmt, va_list ap) { return vsnprintf(s, n, fmt, ap); } int __vsprintf_chk(char *s, int flag, size_t size, const char *fmt, va_list ap) { return vsprintf(s, fmt, ap); } > U __sysv_signal use signal > So, I am wondering if the musl library could at some point provide > these routines to enable users to do what I am trying to do. compiling with glibc headers and then linking to musl cannot be supported in general, because of ABI compat issues (eg glibc headers define PTHREAD_*_INITIALIZER macros that hardcode glibc internal ABI at compile time that does not match musl) if you are sure you don't have such ABI breakage (see glibc vs musl differences on the wiki) then you may get away by adding a glibc-compat.o to your musl build > > Any possibility of that? > > Thanks, > Dave