Makefile.include: remove RIOT_VERSION_OVERRIDE

RIOT_VERSION is not used for building a specific RIOT version anymore
since #10543. The variable can now be used directly.
Add deprecation warning.

Makefile.include

@@ -320,7 +320,7 @@ endif
 
 # set some settings useful for continuous integration builds
 ifeq ($(RIOT_CI_BUILD),1)
-    RIOT_VERSION_OVERRIDE:=buildtest
+    RIOT_VERSION ?= buildtest
     ifneq ($(filter $(BOARD_INSUFFICIENT_MEMORY), $(BOARD)),)
         $(info CI-build: skipping link step)
         RIOTNOLINK:=1
@@ -353,6 +353,12 @@ include $(RIOTMAKE)/cflags.inc.mk
 include $(RIOTMAKE)/git_version.inc.mk
 RIOT_VERSION ?= $(or $(GIT_VERSION),'UNKNOWN (builddir: $(RIOTBASE))')
 
+# Deprecate using RIOT_VERSION_OVERRIDE but currently keep the behavior
+ifneq (,$(RIOT_VERSION_OVERRIDE))
+  $(warning 'RIOT_VERSION_OVERRIDE' is deprecated, it can now be set with 'RIOT_VERSION' directly.)
+  RIOT_VERSION = $(RIOT_VERSION_OVERRIDE)
+endif
+
 # Set module by prepending APPLICATION name with 'application_'.
 # It prevents conflict with application and modules with the same name.
 APPLICATION_MODULE ?= application_$(APPLICATION)
@@ -724,12 +730,7 @@ $(RIOTBUILD_CONFIG_HEADER_C): FORCE
 # Immediate evaluation but keep CLAGS_WITH_MACROS deferred
 _CFLAGS := $(CFLAGS)
 CFLAGS_WITH_MACROS = $(_CFLAGS)
-
-ifneq (,$(RIOT_VERSION_OVERRIDE))
-  CFLAGS_WITH_MACROS += -DRIOT_VERSION=\"$(RIOT_VERSION_OVERRIDE)\"
-else
-  CFLAGS_WITH_MACROS += -DRIOT_VERSION=\"$(RIOT_VERSION)\"
-endif
+CFLAGS_WITH_MACROS += -DRIOT_VERSION=\"$(RIOT_VERSION)\"
 
 CFLAGS := $(patsubst -D%,,$(CFLAGS))
 CFLAGS := $(patsubst -U%,,$(CFLAGS))

makefiles/buildtests.inc.mk

@@ -11,7 +11,7 @@ buildtest:
 	for board in $(BOARDS); do \
 		if BOARD=$${board} $(MAKE) check-toolchain-supported > /dev/null 2>&1; then \
 			$(COLOR_ECHO) -n "Building for $$board ... " ; \
-			BOARD=$${board} RIOT_CI_BUILD=1 RIOT_VERSION_OVERRIDE=buildtest \
+			BOARD=$${board} RIOT_CI_BUILD=1 \
 				$(MAKE) clean all -j $(NPROC) $(BUILDTEST_MAKE_REDIRECT); \
 			RES=$$? ; \
 			if [ $$RES -eq 0 ]; then \