https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96016
--- Comment #4 from Bu Le <bule1 at huawei dot com> --- (In reply to Andreas Schwab from comment #3) > You are computing the sine of (double)ld. If you want the sine of a long > double value, you need to use the sinl function, also use acosl(-1) to > compute pi in long double precision. Oh, I see. Thanks for help.