[PATCH] Fix PR ada/33857 on Mac OS X 10.5.2

[Arnaud Charlet]

> The enclosed change fixes ada bootstrap on i686-apple-darwin9.
> Charles Lambert spotted that Apple changed the behavior of putenv
> so that it no longer copies its input buffer.  As a result, the
> freeing of the input buffer in env.c caused bad things to happen.
> 
> The trick in testing this patch was to find a version of gnat
> unaffected by the bug.  Once a working version of gnat is installed,
> gnat builds consistently and the testsuite is clean on the 4.3
> branch.
> 
> Ok to install on trunk and 4.3?

Is this change correct on all versions of darwin or only recent ones ?
>From what you're saying above, "Apple *changed* the behavior of
putenv", so could you clarify which versions will work and which won't
(i.e. will no longer be properly supported after your proposed change) ?

Isn't there a way (as done for freebsd) to differentiate between versions
of darwin ?

Arno