How are weaks elided from single-threaded processes?

[Peter S. Mazinger]

Hello!

In libc-lock.h I found this comment:
/* Make the pthread functions weak so that we can elide them from 
single-threaded processes.  */

Could someone please explain how this works?

Does it apply only to the static libs, or does it make sense for the 
shared ones as well?

If these weaks are "automagically" elided from shared libs as well, then I 
am wondering if the check in forward.c FORWARD2 macro is not superfluos.

Thanks, Peter

P.S. Please CC, not on list.

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Peter S. Mazinger <ps dot m at gmx dot net>           ID: 0xA5F059F2
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