8218807: Compilation database (compile_commands.json) may contain obs…

…olete items

Reviewed-by: ihse, erikj

make/Main.gmk

@@ -784,6 +784,8 @@ else
   $(foreach m, $(GENSRC_MODULES), $(eval $m-libs-compile-commands: $m-gensrc))
   $(foreach m, $(filter $(JAVA_MODULES), $(LIBS_MODULES)), $(eval $m-libs-compile-commands: $m-java))
 
+  $(COMPILE_COMMANDS_TARGETS_HOTSPOT): clean-compile-commands
+  $(COMPILE_COMMANDS_TARGETS_JDK): clean-compile-commands
   compile-commands-hotspot: $(COMPILE_COMMANDS_TARGETS_HOTSPOT)
   compile-commands: $(COMPILE_COMMANDS_TARGETS_HOTSPOT) $(COMPILE_COMMANDS_TARGETS_JDK)
 
@@ -1138,6 +1140,9 @@ clean: $(CLEAN_DIR_TARGETS)
 clean-docs:
 	$(call CleanDocs)
 
+clean-compile-commands:
+	$(call CleanMakeSupportDir,compile-commands)
+
 $(CLEAN_DIR_TARGETS):
 	$(call CleanDir,$(patsubst clean-%, %, $@))
 
@@ -1179,9 +1184,9 @@ dist-clean: clean
 	)
 	$(ECHO) Cleaned everything, you will have to re-run configure.
 
-ALL_TARGETS += clean clean-docs dist-clean $(CLEAN_DIR_TARGETS) $(CLEAN_SUPPORT_DIR_TARGETS) \
-    $(CLEAN_TEST_TARGETS) $(CLEAN_PHASE_TARGETS) $(CLEAN_MODULE_TARGETS) \
-    $(CLEAN_MODULE_PHASE_TARGETS)
+ALL_TARGETS += clean clean-docs clean-compile-commands dist-clean $(CLEAN_DIR_TARGETS) \
+    $(CLEAN_SUPPORT_DIR_TARGETS) $(CLEAN_TEST_TARGETS) $(CLEAN_PHASE_TARGETS) \
+    $(CLEAN_MODULE_TARGETS) $(CLEAN_MODULE_PHASE_TARGETS)
 
 ################################################################################
 # Declare *-only targets for each normal target

make/MainSupport.gmk

@@ -65,6 +65,13 @@ define CleanSupportDir
 	@$(PRINTF) " done\n"
 endef
 
+define CleanMakeSupportDir
+	@$(PRINTF) "Cleaning $(strip $1) make support artifacts ..."
+	@$(PRINTF) "\n" $(LOG_DEBUG)
+	$(RM) -r $(MAKESUPPORT_OUTPUTDIR)/$(strip $1)
+	@$(PRINTF) " done\n"
+endef
+
 define CleanTest
 	@$(PRINTF) "Cleaning test $(strip $1) ..."
 	@$(PRINTF) "\n" $(LOG_DEBUG)