Dealing with compilers that pretend to be GCC

[Ludovic Courtès]

Hello,

Chris Lattner <clattner@apple.com> skribis:

> On Jan 20, 2012, at 5:24 PM, Jonathan Wakely <jwakely.gcc@gmail.com> wrote:
>
>> On 21 January 2012 00:32, Vincent Lefevre wrote:
>>> On 2012-01-20 23:28:07 +0000, Jonathan Wakely wrote:
>>>> May I politely suggest that this is the wrong place to complain about
>>>> other compilers pretending to be GCC :)
>>> 
>>> I think that's the fault of GCC, which should have defined a macro
>>> for each extension.
>> 
>> And what about the fact other compilers haven't defined such a macro
>> for each extension they implement, whether it comes from GCC or not,
>> is that GCC's fault too?
>
> If fact, some do:
> http://clang.llvm.org/docs/LanguageExtensions.html#feature_check

That seems like a very useful approach to solve the problem.

The docs say that ‘__has_builtin’ & co. are macros.  What do they expand to?  

Thanks,
Ludo’.