Using GCC to verify code has no "functional change".

[Ángel González]

On 31/10/12 07:23, John Steele Scott wrote:
> This code has quite a few places where __LINE__ is used when building error
> messages. The frmat change results in some line numbers changing, and so I still
> need to eyeball the diff t ensure that only line numbers are different.
>
> I tried forcing __LINE__ to be a constant on the command line (with
> -D__LINE__=0), but thatfails with '<command-line>: error: "__LINE__" redefined'.

You could replace all uses of __LINE__ with LINE, and then use
-DLINE=__LINE__ in
the normal build, and -DLINE=123 in the comparison one.

Note however that in some cases __LINE__ is used to force
macro-generated identifiers
to be different, so if your code base does that you could end up with
symbols defined
multiple times when setting it to a constant.

Regards