Update.

[thirdparty/glibc.git] / FAQ

diff --git a/FAQ b/FAQ
index c37ae5b7edcf3f6cdff7a2c04bce475d1e517008..b1e4da343f0286d178642ca415b374e97f7b5b91 100644 (file)
--- a/FAQ
+++ b/FAQ
@@ -97,6 +97,9 @@ please let me know.
 [Q27]  ``Programs like `logname', `top', `uptime' `users', `w' and
          `who', show incorrect information about the (number of)
          users on my system.  Why?''
+
+[Q28]  ``After upgrading to a glibc 2.1 with symbol versioning I get
+         errors about undefined symbols.  What went wrong?''
 \f
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 [Q1]   ``What systems does the GNU C Library run on?''
@@ -733,13 +736,32 @@ symlink that you have in place before you install glibc.  However,
 [A27] {MK} See Q10.
 
 
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+[Q28]  ``After upgrading to a glibc 2.1 with symbol versioning I get
+         errors about undefined symbols.  What went wrong?''
+
+[A28] {AJ} In a versioned libc a lot of symbols are now local that
+have been global symbols in previous versions. When defining a extern
+variable both in a user program and extern in the libc the links
+resolves this to only one reference - the one in the library. The
+problem is caused by either wrong program code or tools. In no case
+the global variables from libc should be used by any program. Since
+these reference are now local, you might see a message like:
+
+"msgfmt: error in loading shared libraries: : undefined symbol: _nl_domain_bindings"
+
+The only way to fix this is to recompile your program. Sorry, that's
+the price you might have to pay once for quite a number of advantages
+with symbol versioning.
+
+
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 \f
 Answers were given by:
 {UD} Ulrich Drepper, <drepper@cygnus.com>
 {DMT} David Mosberger-Tang, <davidm@AZStarNet.com>
-{RM} Roland McGrath, <roland@gnu.ai.mit.edu>
-{HJL} H.J. Lu, <hjl@gnu.ai.mit.edu>
+{RM} Roland McGrath, <roland@gnu.org>
+{HJL} H.J. Lu, <hjl@gnu.org>
 {AJ} Andreas Jaeger, <aj@arthur.rhein-neckar.de>
 {EY} Eric Youngdale, <eric@andante.jic.com>
 {PB} Phil Blundell, <Philip.Blundell@pobox.com>