build/docs/environment-variables.rst
author Iain Ireland <iireland@mozilla.com>
Fri, 11 Jan 2019 18:05:36 +0000
changeset 453523 025feea5945bffc625e9cca2e23be51ee8670315
parent 193245 7ac8d502c5948902b7ccacc6d10d013b20764a92
permissions -rw-r--r--
Bug 1480390: Move ForOfIterClose logic inside TryNoteIter r=tcampbell This patch was intended to be a pure refactoring of existing code with no side-effects, moving the logic for handling for-of/for-of-iterclose trynotes inside TryNoteIter to avoid duplicating logic in all users of TryNoteIter. However, it turns out that there was a subtle preexisting bug in TryNoteIter that is fixed by the refactoring. Specifically, the logic to skip from a for-of-iterclose to its enclosing for-of must run before the logic to skip trynotes based on stack depth. Otherwise, the stack depth code may filter out the enclosing for-of (see the attached test case for an example) and we will skip too many try-notes. Differential Revision: https://phabricator.services.mozilla.com/D14783

.. _environment_variables:

================================================
Environment Variables Impacting the Build System
================================================

Various environment variables have an impact on the behavior of the
build system. This document attempts to document them.

AUTOCLOBBER
   If defines, the build system will automatically clobber as needed.
   The default behavior is to print a message and error out when a
   clobber is needed.

   This variable is typically defined in a :ref:`mozconfig <mozconfig>`
   file via ``mk_add_options``.

REBUILD_CHECK
   If defined, the build system will print information about why
   certain files were rebuilt.

   This feature is disabled by default because it makes the build slower.

MACH_NO_TERMINAL_FOOTER
   If defined, the terminal footer displayed when building with mach in
   a TTY is disabled.

MACH_NO_WRITE_TIMES
   If defined, mach commands will not prefix output lines with the
   elapsed time since program start. This option is equivalent to
   passing ``--log-no-times`` to mach.