https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102930
--- Comment #1 from Vincent Lefèvre <vincent-gcc at vinc17 dot net> --- I forgot some information: Debian unstable currently has libc6 2.32-4, where IBM's code for correct rounding was disabled some time ago. This bug might be unreproducible with other glibc versions (or other C libraries[*]). A change of the tested function and argument should make the same kind of issue appear on other platforms. However, I've just done a test on a Debian 10 (buster) machine (libc6 2.28-10), and the bug is reproducible on this machine. [*] A result may be correctly rounded by chance; this completely depends on the implementation.