On Thu, 17 Jan 2002, Bill Studenmund wrote:

> On 17 Jan 2002, Darrin B. Jewell wrote:
>
> >
> > Compiling with the old toolchain should still work, although it
> > would be tested first.
> >
> > They are protected by
> >   ``#if __GNUC_PREREQ__(2, 95)''
> >
> > Darrin
>
> The resulting binaries work the same way, don't they? i.e. if we make this
> change & install the new headers, we can compile variargs programs (say
> something using printf()) that will work with programs built on the old
> toolchain (say libc)?

Let me try that again.

This question is now more of a toolchain/abi one, that I think neither
Darrin nor I can answer.

Say we update the include file (lost which one, but on the 1.5 branch) so
that it has variarg support for the new toolchain. Say I then do a make
includes from the kernel, and then compile a program that uses a variargs
function (say printf() for example). I then link that program against a
libc made with the old compiler. Will the program work?

If so, the I think it's fine to back-port the new variargs stuff,
conditional on the gcc version.

Take care,

Bill