How to get C function names in diffs?

[Peter Weilbacher]

In my Hg config I set
   [defaults]
   diff=-p
(equivalent to |diff --show-c-function|) to see function names of my code in the
patches. For |hg diff| itself this works nicely, but elsewhere Hg
creates/displays patches this has no effect. My main cases would be to get the
function names displayed are in the patches that Mq creates (i.e. .hg/patches/*)
and in the webpage output that I get from |hg serve|.

I'm using Mercurial Distributed SCM (version 1.9.1) on Gentoo Linux.

Thanks in advance for any hints!
   Peter.