libtool breaks versioning information on symbols in libpthread.

[Carlo Wood]

When compiling a shared library that uses threads, I pass
-pthread to the compiler as option.  There is no need to
pass -lpthread to the compiler in that case.

Also libtool does not pass -lpthread when not explicitely
provided by the user.

This leads to a very nasty bug that is hard to spot/find:
Because there is no -lpthread during linking of the shared
library, there is no versioning information available.
As a result, functions that are a part of this library will
call the wrong (old) functions.

There are two solutions:
1) Libtool should pass -lpthread to the linking stage
   when it spots -pthread as argument.
2) Get gcc to do that itself.

I don't think that 2) is a reasonable option from YOUR point
of view, because that would mean that libtool will stay BROKEN
until this is added to -say- gcc-3.1, and even then continuous
to be broken for all older compiler versions.

-- 
Carlo Wood <address@hidden>

PS Attached the last mail from H.J.Lu who found the
   solution to this problem (see binutils mailing
   archive if you want more details).

msg.hAf
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