Re: global vars and symbol visibility for mips32/elf

[Ulrich Drepper <drepper@cygnus.com>]

From: Ian Lance Taylor <ian@cygnus.com>
Subject: Re: global vars and symbol visibility for mips32/elf
Date: Fri, 9 Aug 1996 11:29:54 -0400

>    The problem is caused by the symbol 'glob'.  GNU libc also has a
>    symbol glob.
> 
> This is the bug.  An ANSI C compliant shared library may not have a
> global symbol which infringes on the ANSI C namespace.  The symbol
> must, instead, be weak.

Why should `glob' be made weak?  In GNU libc we make a symbol only
weak if necessary.  It is correct that no symbol in a ISO C lib
must have this name.  But if the object file in the shared lib which
contains the definition of glob is transitively not used by any ISO C
function this is ok.  At least this is what I currently know.

Reading your words it seems that using a shared lib introduces *all*
symbols of the shared lib in the namespace of the application.  I.e.,
all symbols not mentioned in ISO C must be weak.  Is this how it is
implemented in GNU ld and how it is intend in ELF?

If yes, this would mean that nearly every symbol in the shared lib
must be weak.

Thanks,

-- Uli
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