[Bug other/86857] configure sprintf with target-specific details

[joseph at codesourcery dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86857

--- Comment #2 from joseph at codesourcery dot com <joseph at codesourcery dot com> ---
A configure test can only test what sprintf does for the host, not for the 
target, so this would always need to be a target hook.

Even with a hook, it would not surprise me if e.g. results on MinGW depend 
on __USE_MINGW_ANSI_STDIO, so you can't assume there is always a constant 
answer for these questions.