Re: gnulib m4/threadlib.m4 bug crashing package tests

[Brian Inglis <Brian.Inglis@SystematicSw.ab.ca>]

On 2021-11-28 09:23, Achim Gratz wrote:
> Achim Gratz writes:
>> I'd rather know why the bleeping heck the test suddenly succeeds when it
>> clearly doesn't actually work.  In other words, I think the linker
>> should complain, but since it obviously did that before Cygwin 3.2.0 and
>> not after, something must have changed somewhere that prevent s it from
>> doing that.
> 
> So the exact same problem was discussed in 2010 and the test that's
> still there conceived that checks if the returned symbol for weakly
> defined fputs is NULL (which would then disable weak symbols for
> gnulib).  That obviously still happens on 32bit, but no longer on 64bit.
> I think the test is bogus in both cases since the executable will always
> be linked again cygwin1.dll and so should be able to resolve the symbol
> either way.

Bruno Haible (gnulib maintainer) also patched the current gnulib on 
request from Akim Demaille (bison maintainer).

The problem with Cygwin weak symbols is apparently that ld expects there 
to be a runtime dynamic loader to resolve NULL weak dynamic library 
references, but unlike ELF neither Cygwin nor Windows does so, and PE 
may not retain the information to do so, or this project would likely 
have done so.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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