When trying to make xserver (git version) I get the following error:
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Making all in mi
make[1]: Entering directory '/home/jos/src/xorg/git/xserver/mi'
  CC       miarc.lo
miarc.c:89:1: error: static declaration of 'cbrt' follows non-static declaration
 cbrt(double x)
 ^
In file included from /usr/include/features.h:361:0,
                 from /usr/include/math.h:26,
                 from miarc.c:53:
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:169:1: note: previous declaration of 'cbrt' was here
 __MATHCALL (cbrt,, (_Mdouble_ __x));
 ^
Makefile:716: recipe for target 'miarc.lo' failed
make[1]: *** [miarc.lo] Error 1
make[1]: Leaving directory '/home/jos/src/xorg/git/xserver/mi'
Makefile:769: recipe for target 'all-recursive' failed
make: *** [all-recursive] Error 1
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