[PATCH] Fix build if __GLIBC_PREREQ is not defined

Thorsten Glaser tg at mirbsd.de
Fri Mar 2 12:46:22 UTC 2018

Jörg Krause dixit:

>Fixes build error with musl:

musl doesn't define __GLIBC__ so the second check in...

> #if defined(_GNU_SOURCE) && defined(__GLIBC__) && !__GLIBC_PREREQ(2, 26)

... suffices already.

If you run into this, it must be a local problem,
i.e. someone defined __GLIBC__ on a non-glibc system,
since cpp short-circuits such an evaluation, and this
is the documented way to use __GLIBC_PREREQ().

In traditional syntax ' is ignored, but in c99 everything between two ' is
handled as character constant.  Therefore you cannot use ' in a preproces-
sing file in c99 mode.	-- Ragge
No faith left in ISO C99, undefined behaviour, etc.

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