https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117023
--- Comment #5 from Bruno Haible <bruno at clisp dot org> --- (In reply to Jakub Jelinek from comment #4) > I think it is just fine to call strncat (s, NULL, 0); because it will > read no more than 0 characters from src, but I think it is problematic to > call strncat (NULL, s, 0); > or strncat (NULL, NULL, 0); because it can't always append the null > character to that. I agree, because the standard talks about "the string pointed to by s1", and that implies that s1 is already NUL-terminated before strncat is called. Likewise for wcsncat; see https://sourceware.org/bugzilla/show_bug.cgi?id=32286#c2 .
