Quilt and cutting down diff position lines

[Adrian Schmutzler]

> -----Original Message-----
> From: Adrian Schmutzler [mailto:mail at adrianschmutzler.de]
> Sent: Mittwoch, 24. Februar 2021 11:50
> To: 'openwrt-devel at lists.openwrt.org' <openwrt-devel at lists.openwrt.org>
> Subject: Quilt and cutting down diff position lines
> 
> Hi,
> 
> as most are probably aware, quilt cuts down the position lines in patches
> during refresh:
> 
> - @@ -78,7 +78,8 @@ void machine_apply_elf_rel(struct mem_ehdr
> *UNUSED(ehdr),
> + @@ -78,7 +78,8 @@ void machine_apply_elf_rel(struct mem_eh
> 
> While this has no functional impact, it creates a lot of additional spam
during
> checkpatch.pl, and it makes these lines less useful for the frequent cases
> where the relevant (meaning "specific") information is at the end of that
line
> (i.e. when looking at patches directly). Apart from that, this also bloats
diffs in
> packages when people add proper patches, and quilt will then just cut down
> these lines without a change in position.
> 
> I wonder whether quilt can be convinced to not cut this line (did not find
any
> helpful guidance so far), and whether one wants to change that if it's
> possible?

Well, after a lengthy quest into the world of quilt, I found that this is
actually a diff "bug", since diff hardcodes the context function to 40
characters max:

https://git.savannah.gnu.org/cgit/diffutils.git/tree/src/context.c#n156

And since this is a prerequisite the user installs on the host, we cannot do
much about it either, as it appears.

> 
> Best
> 
> Adrian
>