mach configure
then check that the changes are in $OJBDIR/config.status, and then build normally.
==== ccache ====
You can optionally install [https://developer.mozilla.org/en-US/docs/Ccache ccache], which can make rebuilding Firefox faster after you have built it once and don't change (much) of the C++ source code. In general, ccache is not a performance improvement if you use only one object directory, or edit only Java and/or JavaScript source code.
If you want to use ccache, add a line the following to your mozconfig:
ac_add_options --with-ccache[=/optional/path/to/ccache]
The default cache size of 1GB is not large enough for a Fennec build. To fully utilize ccache (generally meaning you can expect full builds to complete in <5 minutes from a populated cache), you'll need to change the cache size to at least 4GB. Do so by running:
ccache --max-size 4G
On Mac OS X, install ccache like:
brew install ccache
On Debian-like Linuxes, install ccache using:
sudo apt-get install mercurial ccache
==== Building for the x86 architecture ====
for the target specified above. Note: you cannot use <tt>ac_add_options --disable-optimize</tt> when building for x86. See {{bug|965870}}.
==== Building Gingerbread-only ====
For legacy Gingerbread devices, there is a Gingerbread-only build that is optimized for performance and apk size for older devices but does not include some of the newer features that are available.
To make a Gingerbread-only build, you need to use a different [https://dxr.mozilla.org/mozilla-central/source/mobile/android/config/mozconfigs/android-api-9-10-constrained/nightly mozconfig].
==== Building for the ARMv6 architecture ====
ac_add_options --with-arch=armv6
==== Building different channels ====
If you want to build different channels (through the Try server, for example), you need to add this to mobile/android/config/mozconfigs/common.override:
ac_add_options --enable-update-channel=nightly
To change the branding, add:
ac_add_options --with-branding=browser/branding/nightly
These can be changed to any of the following channels (nightly, beta, release).
==== Unsupported build flags ====
