Re: vasnprintf's "%n in writable segment" chokes with _FORTIFY_SOURCE == 2

[Paul Eggert]

Jim Meyering <address@hidden> writes:

> vasnprintf.c should resort to incurring the
> expense of that portability kludge only when necessary.
> How about if it does that only when a configure-time test
> has detected that snprintf's return value is not conforming?

That sounds like a good idea.

How common is it for snprintf to return the wrong value?  If it's not
that common, perhaps we can just not worry about those systems at all.

I can't resist mentioning a more-fun workaround.  We can put a
snprintf wrapper into gnulib that copies the format string into a
buffer, uses mmap to make the buffer read-only, and then calls the
real snprintf.  Sort of an "anti-Fortify" wrapper, if you will.