Cut down global compilation time, see details:

- When running multiple makefiles' install target, you should NEVER
  EVER depend on the plain 'all' target!!!! 'install' already depends
  on 'all' inside each makefile. Failure to abide by this can
  unnecessarily multiply the number of times makefiles are called.
  Previously the unixtool makefiles were being processed EIGHT times!
- The apps folder now has its own userlibs-like makefile
- The unixtools makefile has been replaced with a userlibs-like one

Makefile

@@ -1,6 +1,3 @@
-SUBDIRS  := $(patsubst %/,%,$(dir $(wildcard */Makefile)))
-APPS     := $(patsubst %/,%,$(dir $(wildcard apps/*/Makefile)))
-
 ifeq ($(FEOSDEST),)
 export FEOSDEST = $(FEOSSDK)/../FeOS
 endif
@@ -17,22 +14,24 @@ endif
         sdk  sdkclean  sdkinstall\
         lib  libclean  libinstall\
         apps appsclean appsinstall\
-        $(APPS)
+        outputfolders
 
 ################################################################################
 # generic rules
 ################################################################################
 all: $(ALL)
-	@mkdir -p $(FEOSDEST)/data/FeOS/bin
-	@mkdir -p $(FEOSDEST)/data/FeOS/lib
-	@mkdir -p $(FEOSDEST)/data/FeOS/arm7
 
 clean: $(addsuffix clean,$(ALL))
 	@rm -f $(FEOSDEST)/data/FeOS/bin/*
 	@rm -f $(FEOSDEST)/data/FeOS/lib/*
 	@rm -f $(FEOSDEST)/data/FeOS/arm7/*
 
-install: all $(addsuffix install,$(ALL))
+install: $(addsuffix install,$(ALL))
+
+outputfolders:
+	@mkdir -p $(FEOSDEST)/data/FeOS/bin
+	@mkdir -p $(FEOSDEST)/data/FeOS/lib
+	@mkdir -p $(FEOSDEST)/data/FeOS/arm7
 
 ################################################################################
 # 'all' rules
@@ -46,10 +45,8 @@ sdk:
 lib: sdk
 	@$(MAKE) --no-print-directory -C sdk/userlib
 
-apps: lib $(APPS)
-
-$(APPS): lib
-	@$(MAKE) --no-print-directory -C $@
+apps: lib
+	@$(MAKE) --no-print-directory -C apps
 
 ################################################################################
 # 'clean' rules
@@ -64,22 +61,19 @@ libclean:
 	@$(MAKE) --no-print-directory -C sdk/userlib clean
 
 appsclean:
-	@for i in $(APPS); do $(MAKE) --no-print-directory -C $$i clean; done
+	@$(MAKE) --no-print-directory -C apps clean
 
 ################################################################################
 # 'install' rules
 ################################################################################
-sdkinstall: sdk
+sdkinstall: sdk outputfolders
 	@cp kernel/FeOS.nds $(FEOSDEST)/FeOS.nds
 	@cp kernel/FeOSd.nds $(FEOSDEST)/FeOSd.nds
 	@cp sdk/feoscxx.fx2 $(FEOSDEST)/data/FeOS/lib/feoscxx.fx2
 	@[ -e $(AUTOEXEC) ] || touch $(AUTOEXEC)
 
-libinstall: lib
-	@mkdir -p $(FEOSDEST)/data/FeOS/bin
-	@mkdir -p $(FEOSDEST)/data/FeOS/lib
-	@mkdir -p $(FEOSDEST)/data/FeOS/arm7
+libinstall: outputfolders
 	@$(MAKE) --no-print-directory -C sdk/userlib install
 
-appsinstall: apps
-	@for i in $(APPS); do $(MAKE) --no-print-directory -C $$i install; done
+appsinstall: libinstall
+	@$(MAKE) --no-print-directory -C apps install

apps/unixtools/Makefile

@@ -1,13 +1,18 @@
-SUBDIRS := $(patsubst %/,%,$(dir $(wildcard */Makefile)))
-.PHONY: $(SUBDIRS)
+APPS := $(patsubst %/,%,$(dir $(wildcard */Makefile)))
 
-all: $(SUBDIRS)
+ifeq ($(FEOSDEST),)
+export FEOSDEST = $(FEOSSDK)/../FeOS
+endif
 
-clean:
-	@for i in $(SUBDIRS); do $(MAKE) -C $$i clean; done
+.PHONY: all clean install $(APPS)
 
+all: $(APPS)
+
+clean: TARGET := clean
+clean: all
+
+install: TARGET := install
 install: all
-	@for i in $(SUBDIRS); do $(MAKE) -C $$i install; done
 
-$(SUBDIRS):
-	$(MAKE) -C $@
+$(APPS):
+	@$(MAKE) --no-print-directory -C $@ $(TARGET)

sdk/userlib/Makefile

@@ -9,13 +9,13 @@ endif
 
 all: $(USERLIBS)
 
-clean:
-	@for i in $(USERLIBS); do $(MAKE) --no-print-directory -C $$i clean; done
+clean: TARGET := clean
+clean: all
 
+install: TARGET := install
 install: all
-	@for i in $(USERLIBS); do $(MAKE) --no-print-directory -C $$i install; done
 
 $(USERLIBS):
-	@$(MAKE) --no-print-directory -C $@
+	@$(MAKE) --no-print-directory -C $@ $(TARGET)
 
 -include $(DEPENDS)