Stable Rust currently has logic similar to the following for finding the
linker on Windows:
if VCINSTALLDIR in os.env:
search for things in PATH
if found, return, otherwise fallthrough
look for MSVC installations of various kinds
For our current MozillaBuild setup where we clear out PATH prior to
invoking Cargo, this works: even though VCINSTALLDIR is set and we
(unsuccessfully) search through an empty PATH, we'll still fallback to
looking for MSVC installations.
Beta Rust has altered this search strategy:
if VCINSTALLDIR in os.env:
search for things in PATH
return the result of the search, regardless of success
look for MSVC installations of various kinds
Note that in the above logic, if VCINSTALLDIR is set, we are only going
to try looking in PATH for an appropriate linker. Since PATH is empty
in our current MozillaBuild setup, beta Rust will therefore fail to find
the correct linker. This failure causes numerous problems.
Since Firefox is already trying to "clean" the environment that Cargo is
invoked in, we should work a little bit harder by unsetting VCINSTALLDIR
entirely, and simply force Rust to search for known MSVC installations.
Making this change makes stable and beta Rust behave identically.
(We don't have to worry about this distinction in automation, because
the "cleaning" code is only activated when we detect a MozillaBuild
shell.)
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:
https://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:
https://developer.mozilla.org/en/docs/Creating_a_patch
https://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 https://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 -
https://nightly.mozilla.org/
87007ca0f2