POSIX requires it, cf. https://pubs.opengroup.org/onlinepubs/9699919799/utilities/c99.html#tag_20_11_13_01 https://pubs.opengroup.org/onlinepubs/9699919799/util

POSIX requires it, cf. https://pubs.opengroup.org/onlinepubs/9699919799/utilities/c99.html#tag_20_11_13_01 https://pubs.opengroup.org/onlinepubs/9699919799/utilities/c... However, that "requirement" doesn't prevent you from shipping an empty libm (or other libs listed there.) (The actual reason is probably that glibc is old enough to have lived in a time where you cared about saving time and space by not linking the math functions when you didn't need them...)