RIOT-OS · fjmolinas · Jun 14, 2019 · May 3, 2019 · May 3, 2019 · May 3, 2019
diff --git a/Makefile.dep b/Makefile.dep
@@ -865,13 +865,9 @@ FEATURES_OPTIONAL += periph_pm
 # include package dependencies
 -include $(USEPKG:%=$(RIOTPKG)/%/Makefile.dep)
 
-# remove required features from optional features
-FEATURES_OPTIONAL := $(filter-out $(FEATURES_REQUIRED),$(FEATURES_OPTIONAL))
-
-# add all optional but provided features to the list of used features
-FEATURES_USED := $(sort $(FEATURES_REQUIRED) $(filter $(FEATURES_OPTIONAL),$(FEATURES_PROVIDED)))
 
 # all periph features correspond to a periph submodule
+# FEATURES_USED is defined in Makefile.features
 USEMODULE += $(filter periph_%,$(FEATURES_USED))
 
 # select cpu_check_address pseudomodule if the corresponding feature is used

diff --git a/Makefile.features b/Makefile.features
@@ -1,3 +1,33 @@
 # Process FEATURES variables
 
 include $(RIOTBOARD)/$(BOARD)/Makefile.features
+
+
+# Resolve FEATURES_ variables
+# Their value will only be complete after resolving dependencies
+
+# Features that are required by the application but not provided by the BSP
+# Having features missing may case the build to fail.
+FEATURES_MISSING = $(sort $(filter-out $(FEATURES_PROVIDED),$(FEATURES_REQUIRED)))
+
+# Features that are only optional and not required at the same time.
+# The policy is to by default use by features if they are provided by the BSP.
+FEATURES_OPTIONAL_ONLY = $(sort $(filter-out $(FEATURES_REQUIRED),$(FEATURES_OPTIONAL)))
+FEATURES_OPTIONAL_USED = $(sort $(filter $(FEATURES_PROVIDED),$(FEATURES_OPTIONAL_ONLY)))
+# Optional features that will not be used because they are not provided
+FEATURES_OPTIONAL_MISSING = $(sort $(filter-out $(FEATURES_PROVIDED),$(FEATURES_OPTIONAL_ONLY)))
+
+# Features that are used for an application
+FEATURES_USED = $(sort $(FEATURES_REQUIRED) $(FEATURES_OPTIONAL_USED))
+
+# Used features that conflict when used together
+FEATURES_CONFLICTING = $(sort $(foreach conflict,$(FEATURES_CONFLICT),$(call _features_conflicting,$(conflict))))
+
+# Return conflicting features from the conflict string feature1:feature2
+#   $1: feature1:feature2
+#   Return the list of conflicting features
+_features_conflicting = $(if $(call _features_used_conflicting,$(subst :, ,$1)),$(subst :, ,$1))
+# Check if all features from the list are used
+#   $1: list of features that conflict together
+#   Return non empty on error
+_features_used_conflicting = $(filter $(words $1),$(words $(filter $(FEATURES_USED),$1)))
diff --git a/Makefile.include b/Makefile.include
@@ -622,17 +622,16 @@ ifneq (, $(filter all flash, $(if $(MAKECMDGOALS), $(MAKECMDGOALS), all)))
   endif
 
   # Test if all feature requirements were met by the selected board.
-  ifneq (, $(filter-out $(FEATURES_PROVIDED) $(FEATURES_OPTIONAL), $(FEATURES_REQUIRED)))
+  ifneq (,$(FEATURES_MISSING))
     $(shell $(COLOR_ECHO) "$(COLOR_RED)There are unsatisfied feature requirements:$(COLOR_RESET)"\
-                          "$(sort $(filter-out $(FEATURES_PROVIDED) $(FEATURES_OPTIONAL), $(FEATURES_REQUIRED)))" 1>&2)
+                          "$(FEATURES_MISSING)" 1>&2)
     EXPECT_ERRORS := 1
   endif
 
   # Test if any used feature conflict with another one.
-  CONFLICT := $(foreach var,$(FEATURES_CONFLICT),$(if $(filter $(words $(subst :, ,$(var))),$(words $(filter $(FEATURES_USED),$(subst :, ,$(var))))),$(subst :, ,$(var))))
-  ifneq (, $(strip $(CONFLICT)))
+  ifneq (,$(FEATURES_CONFLICTING))
     $(shell $(COLOR_ECHO) "$(COLOR_YELLOW)The following features may conflict:$(COLOR_RESET)"\
-                          "$(COLOR_GREEN)$(sort $(filter $(FEATURES_USED), $(CONFLICT)))$(COLOR_RESET)" 1>&2)
+                          "$(FEATURES_CONFLICTING)" 1>&2)
     ifneq (, $(FEATURES_CONFLICT_MSG))
         $(shell $(COLOR_ECHO) "$(COLOR_YELLOW)Rationale: $(COLOR_RESET)$(FEATURES_CONFLICT_MSG)" 1>&2)
     endif

diff --git a/makefiles/info-global.inc.mk b/makefiles/info-global.inc.mk
@@ -14,7 +14,6 @@ define board_missing_features
   DISABLE_MODULE    := $(DISABLE_MODULE_GLOBAL)
   FEATURES_REQUIRED := $(FEATURES_REQUIRED_GLOBAL)
   FEATURES_OPTIONAL := $(FEATURES_OPTIONAL_GLOBAL)
-  FEATURES_MISSING  :=
   FEATURES_PROVIDED :=
 
   include $(RIOTBASE)/Makefile.features
@@ -28,12 +27,9 @@ define board_missing_features
 
   include $(RIOTBASE)/Makefile.dep
 
-  FEATURES_MISSING := $$(sort $$(filter-out $$(FEATURES_PROVIDED), $$(FEATURES_REQUIRED)))
-  ifneq (, $$(FEATURES_MISSING))
+  ifneq (,$$(FEATURES_MISSING))
     BOARDS_FEATURES_MISSING += "$(1) $$(FEATURES_MISSING)"
-    ifneq (, $$(filter-out $$(FEATURES_OPTIONAL), $$(FEATURES_MISSING)))
-      BOARDS_WITH_MISSING_FEATURES += $(1)
-    endif
+    BOARDS_WITH_MISSING_FEATURES += $(1)
   endif
 endef
 

diff --git a/makefiles/info.inc.mk b/makefiles/info.inc.mk
@@ -1,6 +1,7 @@
 .PHONY: info-objsize info-buildsizes info-build info-boards-supported \
         info-features-missing info-modules info-cpu \
         info-features-provided info-features-required \
+        info-features-used \
         info-debug-variable-% info-toolchains-supported \
         check-toolchain-supported
 
@@ -46,19 +47,23 @@ info-build:
 	@echo 'HEXFILE: $(HEXFILE)'
 	@echo 'FLASHFILE: $(FLASHFILE)'
 	@echo ''
-	@echo 'FEATURES_REQUIRED (excl. optional features):'
-	@echo '         $(or $(sort $(filter-out $(FEATURES_OPTIONAL), $(FEATURES_REQUIRED))), -none-)'
-	@echo 'FEATURES_OPTIONAL (strictly "nice to have"):'
-	@echo '         $(or $(sort $(FEATURES_OPTIONAL)), -none-)'
+	@echo 'FEATURES_USED:'
+	@echo '         $(or $(FEATURES_USED), -none-)'
+	@echo 'FEATURES_REQUIRED:'
+	@echo '         $(or $(sort $(FEATURES_REQUIRED)), -none-)'
+	@echo 'FEATURES_OPTIONAL_ONLY (optional that are not required, strictly "nice to have"):'
+	@echo '         $(or $(FEATURES_OPTIONAL_ONLY), -none-)'
+	@echo 'FEATURES_OPTIONAL_MISSING (missing optional features):'
+	@echo '         $(or $(FEATURES_OPTIONAL_MISSING), -none-)'
 	@echo 'FEATURES_PROVIDED (by the board or USEMODULE'"'"'d drivers):'
 	@echo '         $(or $(sort $(FEATURES_PROVIDED)), -none-)'
-	@echo 'FEATURES_MISSING (incl. optional features):'
-	@echo '         $(or $(sort $(filter-out $(FEATURES_PROVIDED), $(FEATURES_REQUIRED))), -none-)'
-	@echo 'FEATURES_MISSING (only non-optional features):'
-	@echo '         $(or $(sort $(filter-out $(FEATURES_OPTIONAL) $(FEATURES_PROVIDED), $(FEATURES_REQUIRED))), -none-)'
+	@echo 'FEATURES_MISSING (only non optional features):'
+	@echo '         $(or $(FEATURES_MISSING), -none-)'
 	@echo ''
 	@echo 'FEATURES_CONFLICT:     $(FEATURES_CONFLICT)'
 	@echo 'FEATURES_CONFLICT_MSG: $(FEATURES_CONFLICT_MSG)'
+	@echo 'FEATURES_CONFLICTING:'
+	@echo '         $(or $(FEATURES_CONFLICTING), -none-)'
 	@echo ''
 	@echo -e 'INCLUDES:$(patsubst %, \n\t%, $(INCLUDES))'
 	@echo ''
@@ -128,7 +133,10 @@ info-features-required:
 	@for i in $(sort $(FEATURES_REQUIRED)); do echo $$i; done
 
 info-features-missing:
-	@for i in $(sort $(filter-out $(FEATURES_PROVIDED), $(FEATURES_REQUIRED))); do echo $$i; done
+	@for i in $(FEATURES_MISSING); do echo $$i; done
+
+info-features-used:
+	@for i in $(FEATURES_USED); do echo $$i; done
 
 info-debug-variable-%:
 	@echo $($*)