strerror() not thread-safe -- does it matter?

[Josh Haberman <jhaberman@...>]

Lua uses strerror() in several places (lauxlib.c, liolib.c, luac.c),
but it is not thread-safe.  On my system (OS X) strerror's static
buffer is initialized to all-NULL, and therefore guaranteed to be
NULL-terminated (even with racing writes), but are there systems where
a race could crash the program?  An extremely low chance of an
incorrect/garbled message seems acceptable, but the potential for a
crash (or even a security exploit) seems bad.

Has this come up before?

Josh