meson: don't use compiler.has_header

Meson's compiler.has_header is completely useless, it only checks that a
header exists, not whether it's usable. This creates problems if a
header contains a conditional #error declaration, like so:

> #if __x86_64__
> # error "Doesn't work with x86_64!"
> #endif

Compiler.has_header will return true in this case, even when compiling
for x86_64. This is useless.

Instead, we'll do a compile check so that any #error declarations will
be treated as errors, and compilation will work.

Fixes compilation on x32 architecture.

Gentoo Bugzilla: https://bugs.gentoo.org/show_bug.cgi?id=649746
meson bug: https://github.com/mesonbuild/meson/issues/2246
Signed-off-by: Dylan Baker <[email protected]>
Acked-by: Matt Turner <[email protected]>
Reviewed-by: Eric Engestrom <[email protected]>
(cherry picked from commit 8247a30838a74dcdd27cc2468bff8a3d8def640e)
[Juan A. Suarez: resolve trivial conflicts]
Signed-off-by: Juan A. Suarez Romero <[email protected]>

Conflicts:
	meson.build

1 files changed, 1 insertions, 1 deletions

diff --git a/meson.build b/meson.build
index 5eef2227e0f..341d9ae5b43 100644
--- a/meson.build
+++ b/meson.build
@@ -839,7 +839,7 @@ elif cc.has_header_symbol('sys/mkdev.h', 'major')
 endif
 
 foreach h : ['xlocale.h', 'sys/sysctl.h', 'linux/futex.h', 'endian.h']
-  if cc.has_header(h)
+  if cc.compiles('#include <@0@>'.format(h), name : '@0@ works'.format(h))
     pre_args += '-DHAVE_@0@'.format(h.to_upper().underscorify())
   endif
 endforeach