Re: Difference in -E output

[Tom Kacvinsky <tkacvins@gmail.com>]

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On Thu, Oct 27, 2022 at 6:30 PM Segher Boessenkool <
segher@kernel.crashing.org> wrote:

> On Thu, Oct 27, 2022 at 04:22:11PM -0400, Tom Kacvinsky via Gcc-help wrote:
> > I am working on an issue that involves our tool depending on the
> > preprocessed output from gcc -E.
>
> > # 4 "test.c" 3 4
> >
> >         0
> >
> > # 4 "test.c"
> >
> >                     ;
> >
> > }
> >
> >
> > Notice how when the macro EXIT_SUCCESS is expanded, we get several lines
> > around the 0?
>
> I don't get any of the blank lines you have though?
>
> > This is happening for us with GCC 8.3.  But using something as early as
> > 4.8.5 (yeah, I know,
> >
> > bad idea), we get this:
> >
> >
> > int main() {
> >
> >   return 0;
> >
> > }
> >
> >
> > I am pretty sure this is an intentional change.  What I'd like to know is
> > if there is a way of
> >
> > reverting back to the former behavior?  I looked at
>
> -P will do what you want (as a side effect though).  -traditional also
> works (and that one is more intentional).  Neither of those does *only*
> this, but either may be usable for your purposes.
>

A colleague informed me that -ftrack-macro-expansion=0 does exactly what I
want.

Said colleague also told me to call them the next time a question like this
came up.  Haha