Commit messages and the move to git

[Segher Boessenkool]

Hi!

On Mon, Nov 18, 2019 at 03:32:06PM +0000, Richard Earnshaw (lists) wrote:
> I wrote this script for two reasons
>    1) To learn some python (finally I had a good reason to go and do 
> this :)

So I am last now?  Heh.

>    2) To try to improve some of our legacy commit messages, especially 
> where they appear in git as just the name of the author (information 
> that is already readily available in other components.

> So for example, a commit such as this one:
> 
> 2019-10-30  Richard Biener  <rguenther@suse.de>
> 
> 	PR tree-optimization/92275
> 	* tree-vect-loop-manip.c (slpeel_update_phi_nodes_for_loops):
> 	Copy all loop-closed PHIs.
> 
> 	* gcc.dg/torture/pr92275.c: New testcase.
> 
> 
> Would be matched and the line
> 
>    PR tree-optimization/92275 ICE: error: definition in block 11 does 
> not dominate use in block 15 since r277566
> 
> added as a summary

That immediately shows some of the shortcomings of this approach: the
subject line is much too long, but more importantly, it doesn't make
much sense: it is not what the patch does, it is the description of a
bug that is related in some way to this patch.  It is not uncommon for
a commit to not fix the problem mentioned in the bug report (if it *is*
a problem!), or not fix it completely.

Then again, changing all such subject lines to read "patch" could also
already be considered an improvement.


Segher