tree 8fa7cdb5e5c0ed967c4d253d9d595ed4fcb828a9
parent 8cd53243b154fbae56c3a242e17e625c780a6356
author Saleem Abdulrasool <compnerd@compnerd.org> 1501693959 -0700
committer Saleem Abdulrasool <compnerd@compnerd.org> 1501818894 -0700

linux: update header used for `major` macro

Newer versions of glibc indicate that they intend to move the major
macro from sys/types.h to sys/sysmacros.h. Add a check for the header
and include that earlier to ensure that the macro is provided by the
newer header when available/possible. This avoids an unnecessary warning
from the system headers.

Because `config_ac.h` is not available at the right location, we cannot
include the header to check whether the header is available.  Rely on
the compiler provided `__has_include` instead of the configure check.
Adjust the inclusion of `sys/cdefs.h` accordingly.