@isuruf RCP<const Basic> num, den;

RCP<const Basic> i1(integer(1)), i2(integer(2));

SymEngine::as_numer_denom(neg(sqrt(div(i1,i2))), outArg(num), outArg(den));

RCP<const Basic> i1(integer(1)), i2(integer(2));

SymEngine::as_numer_denom(neg(sqrt(div(i1,i2))), outArg(num), outArg(den));

I tried to get numerator and denominator for -1/sqrt(2), but the above gives segfault. Sorry I don't know how to submit a ticket. Thanks!

Remove "neg(...)" and then num=1 and den=1/sqrt(2) are good.