Ping: https://gcc.gnu.org/ml/gcc-patches/2018-07/msg00197.html
On 07/04/18 12:53, Bernd Edlinger wrote:
> Hi,
>
> currently _Pragma("GCC diagnostic ...") does not properly
> work in macro expansions.
>
> Consider the following code:
>
> #define B _Pragma("GCC diagnostic push") \
> _Pragma("GCC diagnostic ignored \"-Wattributes\"")
> #define E _Pragma("GCC diagnostic pop")
>
> #define X() B int __attribute((unknown_attr)) x; E /* { dg-bogus "attribute
> directive ignored" } */
>
> void test1(void)
> {
> X() /* { dg-bogus "in expansion of macro" } */
> }
>
>
> Warnings happen in C++ despite the _Pragma, while C happens to suppress the
> warnings
> more or less by accident.
>
> This is connected to the fact that GCC uses the location of the closing
> parenthesis of the
> function-like macro expansion in the _Pragma, while the rest of the locations
> are relative
> to the macro expansion point, which is the letter X in this case.
>
> This patch changes the location of builtin macros and _Pragma to use the
> macro expansion
> point instead of the closing parenthesis.
>
> A few test cases had to be adjusted, most changes were necessary because the
> __LINE__
> location moved to the macro expansion point, which looks like a straight
> improvement.
>
> In pr61817-2.c the location of __LINE__ depends on -ftrack-macro-expansion,
> when enabled the location of the macro argument is the spelling location,
> while all other
> locations change to the macro expansion point.
>
> The C++ pagma plugin.c is also affected by the change, because the
> input_location is now
> the spelling location of _Pragma in DO_PRAGMA and has to be converted to the
> expansion
> point of the macro to get the expected result.
>
>
> Bootstrapped and reg-tested on x86_64-pc-linux-gnu.
> Is it OK for trunk?
>
>
> Thanks
> Bernd.
>
