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Re: Death to configure.frag
DJ Delorie <dj@redhat.com> writes:
>> The odd-looking idiom 'include /dev/null $(variable)' prevents make
>> from grousing if $(variable) expands to nothing. No, -include does
>> not prevent that error, I tried it.
>
> What I use is this:
>
> ifneq ($(variable),)
> include $(variable)
> endif
>
> On some OSs, opening files is expensive. On DJGPP, for example, the
> entire /dev directory is simulated.
>
> In this case, however, it's easier to have those variables default to
> /dev/null in configure.
Actually, no, it isn't, and I'm a little worried about the existence
of /dev/null on (e.g.) Mingwin anyway. I will revise the patch to use
the ifneq idiom you suggest above.
zw