[Bug sanitizer/94849] Improper parameter validation in libsanitizer for fopen64

[rachel at rachelmant dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94849

--- Comment #7 from Rachel Mant <rachel at rachelmant dot com> ---
Continuing to think on this a bit, and.. if it is undefined behaviour as you
say, then granted this is not a bug on ASAN/TSAN.. but it is still a bug as
UBSAN does and says nothing when faced with this even though it clearly should
terminate the program for invoking UB, with a suitable diagnostic.