Fix unknown type name '__WAIT_STATUS' errors when compiling Julia on systems with older glibc versions.

[mikhail-j]

@StefanKarpinski @ararslan

When I compile Julia v1.0.3 on SUSE SLES 11 SP4, my compilation fails due to one of OpenBLAS's tests:

In file included from test_fork.c:36:0:
/usr/include/sys/wait.h:116:22: error: unknown type name ‘__WAIT_STATUS’
 extern __pid_t wait (__WAIT_STATUS __stat_loc);
                      ^
In file included from test_fork.c:36:0:
/usr/include/sys/wait.h:169:23: error: unknown type name ‘__WAIT_STATUS’
 extern __pid_t wait3 (__WAIT_STATUS __stat_loc, int __options,
                       ^
/usr/include/sys/wait.h:175:38: error: unknown type name ‘__WAIT_STATUS’
 extern __pid_t wait4 (__pid_t __pid, __WAIT_STATUS __stat_loc, int __options,
                                      ^
test_fork.c: In function ‘__ctest_fork_safety_run’:
test_fork.c:114:13: warning: implicit declaration of function ‘wait’ [-Wimplicit-function-declaration]
             pid_t wait_pid = wait(&child_status);
             ^
test_fork.c:116:13: warning: implicit declaration of function ‘WEXITSTATUS’ [-Wimplicit-function-declaration]
             ASSERT_EQUAL(0, WEXITSTATUS (child_status));
             ^
make[3]: *** [test_fork.o] Error 1
make[2]: *** [tests] Error 2
\033[33;1m*** Clean the OpenBLAS build with 'make -C deps clean-openblas'. Rebuild with 'make OPENBLAS_USE_THREAD=0' if OpenBLAS had trouble linking libpthread.so, and with 'make OPENBLAS_TARGET_ARCH=NEHALEM' if there were errors building SandyBridge support. Both these options can also be used simultaneously. ***\033[0m
make[1]: *** [scratch/openblas-e8a68ef261a33568b0f0cf53e0e2287e9f12e69e/build-compiled] Error 1
make: *** [julia-deps] Error 2

This particular issue was introduced in OpenMathLib/OpenBLAS#1450 (bug appears in OpenBLAS v0.3.0).

The software bug fix (OpenMathLib/OpenBLAS#1787) first appeared in OpenBLAS v0.3.4, so OpenBLAS v0.3.0 to v0.3.3 are affected by this bug.

This pull request adds the bug fix as a patch to OpenBLAS v0.3.2 (Julia v1.0.3) during compilation.

In addition, this bug fix could be backported to Julia v0.7.0 (also uses OpenBLAS v0.3.2).

[vchuravy]

Looks good to me.

@staticfloat What is your policy for OpenBLAS patches these days? Should this go though the buildbots/Yggdrasil?

[staticfloat]

For now, Yggdrasil is going to just mirror what happens here; since this is a build system fix (and we don't have build system problems on Yggdrasil) I don't think I'll even bother to carry this patch. So I think this is fine as-is.

[giordano]

Julia 1.0 is no longer supported and we're using a much more recent version of openblas nowadays which includes the proposed fix, so I'm going to close this pull request. Thanks anyway for your contribution!