Re: Keep elog(ERROR) and ereport(ERROR) calls in the cold path - Mailing list pgsql-hackers

David Rowley <dgrowleyml@gmail.com> writes:

> On Tue, 24 Nov 2020 at 12:50, Greg Nancarrow <gregn4422@gmail.com> wrote:
>> Hmmm, unfortunately this seems to break my build ...
>
>> I think your commit needs to be fixed based on the following documentation:
>>
>> https://gcc.gnu.org/onlinedocs/cpp/_005f_005fhas_005fattribute.html#g_t_005f_005fhas_005fattribute
>
> Agreed. I tested on https://godbolt.org/ with a GCC version < 5 and
> updating to what's mentioned in the GCC manual works fine.  What I had
> did not.
>
> Thanks for the report.
>
> I pushed a fix.

The Clang documentation¹ suggest an even neater solution, which would
eliminate the repetitive empty pg_attribute_foo #defines in the trailing
#else/#endif block in commit 1fa22a43a56e1fe44c7bb3a3d5ef31be5bcac41d:

#ifndef __has_attribute
#define __has_attribute(x) 0
#endif

[1] http://clang.llvm.org/docs/LanguageExtensions.html#has-attribute

- ilmari
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