Re: [Emacs-diffs] comment-cache 223d16f 2/3: Apply `comment-depth' text properties when calling `back_comment'.

[Paul Eggert]

On 03/14/2016 12:42 AM, martin rudalics wrote:
> I'd really appreciate some guidelines on this.  My restrictions are two:
>
> (1) Rebuilding Emacs for the sake of debugging a particular problem is
> in general _not_ an option because it takes almost 1/2 an hour here (and
> another 1/2 hour to go back to the previous version).

Yes, it's a pain. It just now took me 9 real-time minutes to go back 
from emacs-25 (commit 4235d2d9eaa3b64d3172f6c60f1e71704795af89) to 
commit 7352c6c695db8b90b63c2601277d64a32507d2bb; this requires a rebuild 
of 'configure' and a re-run of 'configure' and a rebuild of all .o and 
many .elc and info files (including the dreaded "Processing OKURI-NASI 
entries ..." message, I guess because we switched to Unicode 9.0.0 
between those two revisions). I used 'make -j5' on a six-year-old 
four-core desktop (AMD Phenom II X4 910e) running Fedora 23 (GCC 5.3.1), 
with the default optimization of -O2.

When I make a smaller switch, it's faster to rebuild.

> Currently, I've started using '-O2 -g3 -gdwarf-2' throughout but if
> people think that -Og or any other option is preferable, I shall do so
> (I think that I can live with a C-mode slowdown of 25%). 

It might make sense to switch to -Og. This is not quite as good for 
debugging, but in my experience it's usually good enough. More 
specifically, you might try building with CFLAGS='-g3 -Og'.