>> #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
This is solved in glibc CVS.
FX