[PATCH] libgfortran/24313 wrong branch cut for csqrt()

[FX Coudert]

> #include <stdio.h>
> #include <complex.h>
> 
> int main(void) {
>    complex float z;
>    __real__ z =  0.f;
>    __imag__ z = -1.f;
>    z = csqrtf(z);
>    printf("%e %e\n", crealf(z), cimag(z));
> }

http://sources.redhat.com/bugzilla/show_bug.cgi?id=1466