PATCH: ada/14435: [4.2 Regression] gnatchop cannot use the compiled compiler in Ada's testsuite because of changed GCC_EXEC_PREFIX semantics

[Arnaud Charlet]

Note that a related/similar issue is PR 21553. Could you check that
your fix also addresses 21553 ?

Thanks a lot for looking at it.

The next step when/if this patch is committed will be to modify the
acats driver to use GCC_EXEC_PREFIX, which I can take care of.

> The gcc 4.2 manual says
> 
> `GCC_EXEC_PREFIX'
>      If `GCC_EXEC_PREFIX' is set, it specifies a prefix to use in the
>      names of the subprograms executed by the compiler.  No slash is
>      added when this prefix is combined with the name of a subprogram,
>      but you can specify a prefix that ends with a slash if you wish.