Every gfxPrefs::PrefTemplate template declares its own virtual function
overrides for functions declared in gfxPrefs::Pref. The compiler must
therefore create separate copies of each of these virtual functions when
it instantiates PrefTemplate. Since several of these virtual functions
only depend on the template parameter T, the type of the pref, many
instantiations of the functions are identical. The duplicate functions
would normally be merged by identical code folding performed in the
linker, but since these are virtual functions and therefore have their
addresses taken (to be stored in the class's vtable), the linker (at
least for the settings we use for identical code folding) cannot fold
duplicated functions together.
Therefore, we have to do the de-duplication ourselves, by creating an
intermediate templated base class that only depends on the type of the
pref. With this class, only three copies of each virtual function will
be created (one each for bools, floats, and ints). We sneak in
GetLiveValue() into this base class for another small codesize win, even
though it's not a virtual function.
An explanation of the Mozilla Source Code Directory Structure and links to
project pages with documentation can be found at:
https://developer.mozilla.org/en/Mozilla_Source_Code_Directory_Structure
For information on how to build Mozilla from the source code, see:
http://developer.mozilla.org/en/docs/Build_Documentation
To have your bug fix / feature added to Mozilla, you should create a patch and
submit it to Bugzilla (https://bugzilla.mozilla.org). Instructions are at:
http://developer.mozilla.org/en/docs/Creating_a_patch
http://developer.mozilla.org/en/docs/Getting_your_patch_in_the_tree
If you have a question about developing Mozilla, and can't find the solution
on http://developer.mozilla.org, you can try asking your question in a
mozilla.* Usenet group, or on IRC at irc.mozilla.org. [The Mozilla news groups
are accessible on Google Groups, or news.mozilla.org with a NNTP reader.]
You can download nightly development builds from the Mozilla FTP server.
Keep in mind that nightly builds, which are used by Mozilla developers for
testing, may be buggy. Firefox nightlies, for example, can be found at:
https://archive.mozilla.org/pub/firefox/nightly/latest-mozilla-central/
- or -
http://nightly.mozilla.org/