Bug 12773

Summary:	/usr/lib/libc.so is missing an entry for libc.a
Product:	[Retired] Red Hat Linux	Reporter:	stevecassidy <steve.cassidy>
Component:	glibc	Assignee:	Jakub Jelinek <jakub>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	6.2
Target Milestone:	---
Target Release:	---
Hardware:	i386
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2000-06-21 23:53:33 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description stevecassidy 2000-06-21 07:00:28 UTC

I was  having problems linking against a third party library
-- I got undefined symbols for _fxstat and others.  I found
the answer in the glibc FAQ 

http://www.gnu.org/software/libc/glibc-FAQ.html

question 17 talks about what should be in /usr/lib/libc.so and says
that various symbols (fstat included) are undefined in libc.so.6 
and so programs need to link agains libc.a instead. 

The default /usr/lib/libc.so with Redhat 6.2 is:

/* GNU ld script
   Use the shared library, but some functions are only in
   the static library, so try that secondarily.  */
GROUP ( /lib/libc.so.6 /usr/lib/libc_nonshared.a )  

I added an entry for libc.a:

/* GNU ld script
   Use the shared library, but some functions are only in
   the static library, so try that secondarily.  */
GROUP ( /lib/libc.so.6 /usr/lib/libc_nonshared.a /usr/lib/libc.a )  

and my code compiles with no missing symbols.  

I haven't tried to generate a minimal program to reproduce this, but
I just thought I'd share this with you all.

Comment 1 Bill Nottingham 2000-06-21 20:48:15 UTC

You shouldn't be doing that; the unshared symbols should all be present
in libc_nonshared.a. What sort of a library are you linking against?

Comment 2 stevecassidy 2000-06-21 23:53:33 UTC

This is a library from Entropic (now owned by Microsoft)
which reads speech data files.  The linking error
showed a missing _fxstat amongst a few others, nm on
/usr/lib/libc_nonshared.a doesn't show _fxstat, just 
__fxstat while /usr/local/libc.a has both.  

Here's some output from an attempted compile with
the original libc.so:
gcc  -fno-builtin  -O -DSCCS -I/opt/esps531.linux/include -DLINUX -DNO_LIC 
sgram.o  /opt/esps531.linux/lib/libexv.a /opt/esps531.linux/lib/libhdre.a
/opt/esps531.linux/lib/libespsg.a  -lm -o sgram
/opt/esps531.linux/lib/libhdre.a(headers.o): In function `fstat':
/usr/include/sys/stat.h:155: undefined reference to `_fxstat'
/opt/esps531.linux/lib/libhdre.a(headers.o): In function `error_msg':
/home/projects/devel_source/general/src/lib_header/pc_wav.c:798: undefined
reference to `__setjmp'
/home/projects/devel_source/general/src/lib_header/pc_wav.c:798: undefined
reference to `__setjmp'
/home/projects/devel_source/general/src/lib_header/pc_wav.c:798: undefined
reference to `__setjmp'
/home/projects/devel_source/general/src/lib_header/pc_wav.c:798: undefined
reference to `_xstat'
/home/projects/devel_source/general/src/lib_header/pc_wav.c:798: undefined
reference to `_xstat'
/home/projects/devel_source/general/src/lib_header/pc_wav.c:798: undefined
reference to `_fxstat'
/home/projects/devel_source/general/src/lib_header/pc_wav.c:798: undefined
reference to `__setjmp'
/home/projects/devel_source/general/src/lib_header/pc_wav.c:798: undefined
reference to `__setjmp'
/home/projects/devel_source/general/src/lib_header/pc_wav.c:798: undefined
reference to `_xstat'
/opt/esps531.linux/lib/libespsg.a(pfparser.o): In function `stat':
/usr/include/sys/stat.h:135: undefined reference to `_xstat'
/opt/esps531.linux/lib/libespsg.a(putsym.o): In function `stat':
/usr/include/sys/stat.h:135: undefined reference to `_xstat'
collect2: ld returned 1 exit status
make: *** [sgram] Error 1               

This compiles ok with the modified version of libc.so.

Comment 3 Jakub Jelinek 2000-08-24 10:37:37 UTC

The library references internal glibc symbols which are now hidden by
symbol versioning. That is a big no no, implementation of the unexported
symbols may change any time.