[PATCH] libm: Fix 'gamma' and 'gammaf' functions. Clean up other gamma code. [v2]

[Corinna Vinschen]

On Sep  4 09:25, Keith Packard via Newlib wrote:
> The current gamma, gamma_r, gammaf and gammaf_r functions return
> |gamma(x)| instead of ln(|gamma(x)|) due to a change made back in 2002
> to the __ieee754_gamma_r implementation. This patch fixes that, making
> all of these functions map too their lgamma equivalents.
> 
> To fix the underlying bug, the __ieee754_gamma functions have been
> changed to return gamma(x), removing the _r variants as those are no
> longer necessary. Their names have been changed to __ieee754_tgamma to
> avoid potential confusion from users.
> 
> Now that the __ieee754_tgamma functions return the correctly signed
> value, the tgamma functions have been modified to use them.
> 
> libm.a now exposes the following gamma functions:
> 
>     ln(|gamma(x)|):
> 
> 	__ieee754_lgamma_r
> 	__ieee754_lgammaf_r
> 
> 	lgamma
> 	lgamma_r
> 	gamma
> 	gamma_r
> 
> 	lgammaf
> 	lgammaf_r
> 	gammaf
> 	gammaf_r
> 
> 	lgammal	(on machines where long double is double)
> 
>     gamma(x):
> 
> 	__ieee754_tgamma
> 	__ieee754_tgammaf
> 	tgamma
> 	tgammaf
> 	tgammal (on machines where long double is double)
> 
> Additional aliases for any of the above functions can be added if
> necessary; in particular, I'm not sure if we need to include
> __ieee754_gamma*_r functions (which would return ln(|(gamma(x)|).
> 
> Signed-off-by: Keith Packard <keithp@keithp.com>

Pushed.


Thanks,
Corinna