Re: show-portability output (was: Re: 'signbit' patch to use 'copysign' if available)

[Bruno Haible]

Eric Blake wrote:
> > $ ./show-portability copysignf
> > libc                macosx-10.3
> > libcygwin           cygwin
> > libm                cygwin
> 
> The show-portability script output is a bit confusing for cygwin.  Yes,
> the fuction copysignf is provided by linking with cygwin1.dll.  But on the
> link line, there is no -lcygwin, just -lc

Thanks for the remark. I have updated the script at [1] to show libc instead
of libcygwin, so it's easier to understand.

> and -lm is an empty library since everything on cygwin belongs to -lc.

On some other systems as well, some functions occur both in libc and libm.
Yes, that happens. Do I have to filter this out in the output? That would
be distorting. Sometimes (think of pthread functions) the function in libc
is just a stub...

Bruno


[1] http://www.haible.de/bruno/gnu/various-symlists.tar.gz