DeprecatedFeatures

This page is intended to track the various features that are, or will be, deprecated, and their progress through our DeprecationCycle. The idea is to have a place to track movement of these through the cycle so that, within the guidelines of the Cycle, we can be reasonably timely about shedding older features that may be slowing down or complicating the code base.

In the table below, a '?' indicates an estimated or unknown value and a '??' indicates a projected future time. The most recently announced are at the top.

Note that Python version support is handled a bit differently. While there is a small component that is an "active" SCons feature - bytecode strings for certain scenarios - mostly the Python version isn't really part of SCons. Since old versions restrict the syntax that can be used, SCons is now tracking more closely to the versions of cPython supported by upstream and is not using the long deprecation sequence for this.

TODO: Go through old release notes and/or mailing list archives to nail down "Announced."

Stage	Description
Repl	Replacement released
Annuc	Announcement
Hidden	Hidden Warning, off by default, can be turned on
Suppr	Suppressible Warning, on by default, can be turned off
Mand	Mandatory Warning, always on
Fatal	Fatal Error, feature no longer available
Removed	Check removed, may cause Python error

Feature	Description / Notes	Repl	Annuc	Hidden	Suppr	Mand	Fatal	Removed
Python 3.6	Drop support for Python 3.6	N/A	4.8.0	N/A	N/A	N/A	??	??
Python 3.5	Drop support for Python 3.5	N/A	4.2	N/A	N/A	N/A	4.3.0	4.3.0
--cache-<option>	Convert to --cache=<option>	2.1??	2.1??	2.1??	??	??	3.0??	3.2??
${,UN}CHANGED_SOURCES ${,UN}CHANGED_TARGETS reserved variables	Deprecate the user's ability to set them	N/A	1.2	Warning message (and assignment suppressed) as one of the reserved construction variable names
Options/*.py modules	Stub modules, restored when 0.98.1 removed them and broke released configurations	0.98.3	TODO		1.2	2.0	2.1??	3.0??
*Option names	Replaced by *Variable names	0.98.1	TODO		1.2	2.0	2.1??	3.0??
env.BuildDir()	Replaced by env.VariantDir()	0.98.0	TODO		2.0	2.1??	3.0??	3.1.2
build_dir option	Replaced by variant_dir	0.98.0	TODO		2.0	2.1??	3.0??	3.1.2
env.Copy()	Replaced by env.Clone()	0.98.0	TODO		0.98.0	2.0	2.1??	3.1.2
env.SourceSignatures() and env.TargetSignature()	Replaced by env.Decider(); eliminating these would speed up a critical code path!	0.98.0	TODO		0.98.0	2.0	2.1??	3.1.2
--debug=dtree option	Replaced by --tree=derived	0.98.0	TODO		0.98.0	2.0	2.1??	3.1.2
--debug=stree option	Replaced by --tree=all,status	0.98.0	TODO		0.98.0	2.0	2.1??	3.1.2
--debug=tree option	Replaced by --tree=all	0.98.0	TODO		0.98.0	2.0	2.1??	3.1.2
Sig module	Stub module to maintain backwards compatibility from before the Signature Refactoring	0.97.x	TODO		0.98.0	2.0	2.1??	??
scanner Builder keyword	Replaced by separate target_scanner and source_scanner keywords	0.96.90	TODO		0.96.90	2.0	2.1??	3.1.2
overrides Builder keyword	Replaced by use of keyword arguments in Builder creation	0.95	TODO		0.95	2.0	2.1??	3.1.2
--debug=nomemoizer option	No longer has any effect	0.96.94	TODO		0.96.94	2.0	2.1??	3.1.2
File.win32 attribute	Replaced by .windows	0.96.92	TODO	none	2.1??	??	??	??
$WIN32* construction variables	Replaced by $WINDOWS* construction variables	0.96.92	TODO	none	2.1??	??	??	4.2
$PDFCOM construction variable	Replaced by $DVIPDFCOM	0.14	TODO	none	2.1??	??	??	4.2
Taskmaster.Task. needs_execute()	internal method; may be used by user-defined subclasses	should always be overridden - now an abstract method			?	2.0	2.1??	??
Scanner.Scanner class	TBD: unused internal class; may be used by user code	?	?	?	?	?	?	?
Scanner.Selector class	TBD: unused internal class; may be used by user code	?	?	?	?	?	?	?
qt tool	Drop old qt3-only tool	qt4/qt4 contrib	4.3	4.3	?	?	?	?