https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67419
--- Comment #7 from Francois-Xavier Coudert <fxcoudert at gcc dot gnu.org> --- (In reply to r...@cebitec.uni-bielefeld.de from comment #5) > If I drop the __builtin_ and include <stdio.h> and <math.h> instead, I > get the expected Then the math.h header is playing tricks and GCC is not aware. This need to be fixed in the solaris back-end (the same sort of thing happened with darwin in the past, see darwin_patch_builtin in gcc/config/darwin.c). Best bet is to check in math.h how sqrtl() is defined. And then check the assembly code for both the __builtin_sqrtl() and the header-defined sqrtl().
