diff mbox

[libdrm] meson: don't use compiler.has_header

Message ID 20180312181827.24549-1-dylan@pnwbakers.com (mailing list archive)
State New, archived
Headers show

Commit Message

Dylan Baker March 12, 2018, 6:18 p.m. UTC 
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
CC: Matt Turner <mattst88@gmail.com>
Signed-off-by: Dylan Baker <dylan.c.baker@intel.com>
---
 meson.build | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Eric Engestrom March 13, 2018, 2:49 p.m. UTC | #1 
On Monday, 2018-03-12 11:18:27 -0700, Dylan Baker wrote:
> 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
> CC: Matt Turner <mattst88@gmail.com>
> Signed-off-by: Dylan Baker <dylan.c.baker@intel.com>

Nvm my comment on your mesa patch, you've done this already :)

Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>

Sending a couple patches on this bit of the code, they'll be based on
top of this patch.

> ---
>  meson.build | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/meson.build b/meson.build
> index df6f2bd2..a0c79e30 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -186,10 +186,10 @@ else
>    dep_rt = []
>  endif
>  dep_m = cc.find_library('m', required : false)
> -if cc.has_header('sys/sysctl.h')
> +if cc.compiles('#include <sys/sysctl.h>', name : 'sys/sysctl.h works')
>    config.set10('HAVE_SYS_SYSCTL_H', true)
>  endif
> -if cc.has_header('sys/select.h')
> +if cc.compiles('#include <sys/select.h>', name : 'sys/select.h works')
>    config.set10('HAVE_SYS_SELECT_H', true)
>  endif
>  if cc.has_header_symbol('sys/sysmacros.h', 'major')
> -- 
> 2.16.2
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
diff mbox

Patch

diff --git a/meson.build b/meson.build
index df6f2bd2..a0c79e30 100644
--- a/meson.build
+++ b/meson.build
@@ -186,10 +186,10 @@  else
   dep_rt = []
 endif
 dep_m = cc.find_library('m', required : false)
-if cc.has_header('sys/sysctl.h')
+if cc.compiles('#include <sys/sysctl.h>', name : 'sys/sysctl.h works')
   config.set10('HAVE_SYS_SYSCTL_H', true)
 endif
-if cc.has_header('sys/select.h')
+if cc.compiles('#include <sys/select.h>', name : 'sys/select.h works')
   config.set10('HAVE_SYS_SELECT_H', true)
 endif
 if cc.has_header_symbol('sys/sysmacros.h', 'major')