[OE-core] gcc 6.1+ and isystem

[Philip Balister]

On 08/30/2016 11:37 AM, Jack Mitchell wrote:
> Some of the headers shipped with gcc 6.1 and above now use #include_next
> to try to and do clever things with munging system header files. Our
> injection of isystem into the build at 'meta/conf/bitbake.conf' seems to
> be causing some programs to fail to compile. A full explanation can be
> found at [1], a bug report from GCC specifying that it should only be
> used in extreme cases at [2].
> 
> Since we seem to be adding -isystem unconditionally to BUILD_CFLAGS from
> bitbake, and that the default behavior has now changed should this be
> revisited? I'll admit that I am no where near experienced enough with
> GCC and friends internals to make a call on this one, I'm just looking
> for some input.

I think this issue is casuing me trouble building GNU Radio with qt5
support also. I'll try and verify this. I never did figure out where the
-isystem came from. Thanks for the email Jack!

Philip


> 
> Regards,
> Jack.
> 
> [1]
> http://stackoverflow.com/questions/37218953/isystem-on-a-system-include-directory-causes-errors
> 
> [2] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70129