Re: [RFC/PATCH] pager.c: replace git_config with git_config_get_string

Karsten Blees [off-list ref] writes:

If for some reason a config string is accessed after config_cache_free()
(which would be a bug), you won't notice if strings are xstrdup()ed (i.e. git
will continue to run with some invalid configuration). This is IMO much worse
than failing with segfault.

I disagree. In most case, continuing to use the old config value is the
right thing.

First, config_cache_free() is called whenever _any_ configuration
variable is set. So, setting "core.foo" also invalidates "core.bar" in
the cache, while a user of "core.bar" could continue working with the
old, unchanged value.

Then, allowing the invalidation of a config variable at any time raises
a lot of tricky cases (if a command uses a configuration variable twice,
do we really want to implement and test the behavior for all combination
of old/new values for both usages?). More tricky cases usually means
more bugs on the user-side ...

When the code really want the freshest value, it's cheap to re-query the
config cache anyway.

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/