Don't use -finline-limit with Clang.

It's unsupported.

Signed-off-by: Austin Seipp <aseipp@pobox.com>
Ensure gc_thread->wakeup is of type StgWord8.

rtsBool is defined to only have two inhabitants, which are true (1) and
false (0)

But the wakeup flag is set to 4 possible values, outside the range of
rtsBool. This leads Clang to warn about tautological comparisons.

Signed-off-by: Austin Seipp <aseipp@pobox.com>
Ensure gc_type is StgWord8.

Again, the range of gc_type is actually 1-3, which is technically
outside the range of rtsBool.

Signed-off-by: Austin Seipp <aseipp@pobox.com>