[RFC] Make getenv O(1)

[Alexander Monakov]

On Mon, 21 Oct 2013, Ondřej Bílka wrote:
> Why, following does not need synchronization.
> 
> #define GETENV(x) ({ \
>   static char *__ret = NULL; \
>   if (__builtin_constant_p (x) && !__cached) \
>     __ret = getenv (x) + 1; \
>   __builtin_constant_p (x) ? __ret - 1: getenv (x);})

This wouldn't compile as __cached is not defined (and I'll admit I don't see
what approach you're trying to convey).

Alexander