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 <dylan.c.baker@intel.com>
Acked-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>

diff --git a/meson.build b/meson.build
index 3c63f3843815aef2a78c6b2da9d2c333aa20738a..51b470253f5d6b25fe0c2b050655a418b63df6d4 100644 (file)
--- a/meson.build
+++ b/meson.build
@@ -912,7 +912,7 @@ elif cc.has_header_symbol('sys/mkdev.h', 'major')
 endif
 
 foreach h : ['xlocale.h', 'sys/sysctl.h', 'linux/futex.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