On Fri, Nov 27, 2015 at 03:14:52PM +0500, Alexandr Shadchin wrote:
> Fix wrong answer if the imaginary part is zero.
> NetBSD also turn off this piece of code.
>
> See
> http://en.cppreference.com/w/c/numeric/complex/casin
> http://www.wolframalpha.com/input/?i=asin%28-2.0%29
Makes complete sense to me.
FWIW: ok tb@
>
> --
> Alexandr Shadchin
>
> Index: s_casin.c
> ===
> RCS file: /cvs/src/lib/libm/src/s_casin.c,v
> retrieving revision 1.6
> diff -u -p -r1.6 s_casin.c
> --- s_casin.c 3 Jul 2013 04:46:36 - 1.6
> +++ s_casin.c 27 Nov 2015 09:59:45 -
> @@ -63,6 +63,7 @@ casin(double complex z)
> x = creal (z);
> y = cimag (z);
>
> +#if 0
> if (y == 0.0) {
> if (fabs(x) > 1.0) {
> w = M_PI_2 + 0.0 * I;
> @@ -73,6 +74,7 @@ casin(double complex z)
> }
> return (w);
> }
> +#endif
>
> /* Power series expansion */
> /*
> Index: s_casinf.c
> ===
> RCS file: /cvs/src/lib/libm/src/s_casinf.c,v
> retrieving revision 1.3
> diff -u -p -r1.3 s_casinf.c
> --- s_casinf.c20 Jul 2011 19:28:33 - 1.3
> +++ s_casinf.c27 Nov 2015 09:59:45 -
> @@ -65,6 +65,7 @@ casinf(float complex z)
> x = crealf(z);
> y = cimagf(z);
>
> +#if 0
> if(y == 0.0f) {
> if(fabsf(x) > 1.0f) {
> w = (float)M_PI_2 + 0.0f * I;
> @@ -75,6 +76,7 @@ casinf(float complex z)
> }
> return (w);
> }
> +#endif
>
> /* Power series expansion */
> /*
> Index: s_casinl.c
> ===
> RCS file: /cvs/src/lib/libm/src/s_casinl.c,v
> retrieving revision 1.3
> diff -u -p -r1.3 s_casinl.c
> --- s_casinl.c20 Jul 2011 21:02:51 - 1.3
> +++ s_casinl.c27 Nov 2015 09:59:45 -
> @@ -71,6 +71,7 @@ casinl(long double complex z)
> x = creall(z);
> y = cimagl(z);
>
> +#if 0
> if (y == 0.0L) {
> if (fabsl(x) > 1.0L) {
> w = PIO2L + 0.0L * I;
> @@ -81,6 +82,7 @@ casinl(long double complex z)
> }
> return (w);
> }
> +#endif
>
> /* Power series expansion */
> b = cabsl(z);
>
