[toplevel] GCC_NO_EXECUTABLES

[DJ Delorie]

> DJ, I know you asked for this to be added to acx.m4 instead.  Unfortunately,
> it uses constructs that autoconf 2.13 can't parse, thus breaking
> regenerating the toplevel configure.  So I put it in a separate file after
> all.

No version conditionals?

> Tested, along with the patches to follow momentarily, on an extensive
> collection of targets (all --build=i686-linux).  Is this OK?

Ok.

/me wonders if function-per-file is a good precident to start.