Re: [Tinycc-devel] __LINE__ and #line undelying type

[Vincent Lefevre]

On 2021-04-16 07:11:27 +0200, Christian Jullien wrote:
> Even more strange, __LINE__ type changes as it overflows on clang, and gcc:
> 
> int
> main() {
> #line 2147483647
>   printf("__LINE__: %s\n", TYPEOF(__LINE__));
> #line 3000000000
>   printf("__LINE__: %s\n", TYPEOF(__LINE__));
> }
> 
> jullien@sims4:~ $ gcc -std=c11 foo.c -o foo && ./foo
> __LINE__: int
> __LINE__: long long

I think that this is expected. The standard just says that it is an
integer constant, not that it has a fixed type (which could break
many applications, as the largest type would have to be chosen even
for small line numbers). In practice, it just probably gives a
sequence of decimal digits (without a suffix), and the type is
deduced as usual for integer constants.

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Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
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