scons: better handling of implicit dependencies - also add distclean target - refs #1395, #1324, and #1310

Makefile

@@ -1,21 +1,24 @@
 all: mapnik
 
 install:
-	@python scons/scons.py --config=cache --implicit-deps-unchanged --max-drift=1 install
+	@python scons/scons.py --config=cache --implicit-cache --max-drift=1 install
 
 mapnik:
-	@python scons/scons.py --config=cache --implicit-deps-unchanged --max-drift=1
+	@python scons/scons.py --config=cache --implicit-cache --max-drift=1
 
 clean:
-	python scons/scons.py -c --config=cache --implicit-deps-unchanged --max-drift=1
+	@python scons/scons.py -c --config=cache --implicit-cache --max-drift=1
+	@if test -e ".sconsign.dblite"; then rm ".sconsign.dblite"; fi
 
-reset:
+distclean:
 	if test -e ".sconf_temp/"; then rm -r ".sconf_temp/"; fi
 	if test -e ".sconsign.dblite"; then rm ".sconsign.dblite"; fi
 	if test -e "config.cache"; then rm "config.cache"; fi
 
+reset: distclean
+
 uninstall:
-	python scons/scons.py --config=cache --implicit-deps-unchanged --max-drift=1 uninstall
+	python scons/scons.py --config=cache --implicit-cache --max-drift=1 uninstall
 
 test:
 	@echo "*** Running visual tests..."

SConstruct

@@ -1659,11 +1659,6 @@ if not HELP_REQUESTED:
         SetOption('implicit_cache', 1)
         SetOption('max_drift', 1)
 
-    else:
-        # Set the cache mode to 'force' unless requested, avoiding hidden caching of Scons 'opts' in '.sconsign.dblite'
-        # This allows for a SCONS_LOCAL_CONFIG, if present, to be used as the primary means of storing paths to successful build dependencies
-        SetCacheMode('force')
-
     if env['JOBS'] > 1:
         SetOption("num_jobs", env['JOBS'])
 

configure

@@ -1,3 +1,3 @@
 #!/bin/sh
 
-python scons/scons.py --implicit-cache configure "$@"
+python scons/scons.py --implicit-deps-changed configure "$@"