https://bugs.gentoo.org/882611
https://build.opensuse.org/package/view_file/openSUSE:Factory/java-1_8_0-openjdk/make-jobserver-detection.patch?expand=1
--- openjdk/make/MakeHelpers.gmk
+++ openjdk/make/MakeHelpers.gmk
@@ -145,7 +145,7 @@ endef
 
 # Hook to be called as the very first thing when running a normal build
 define AtMakeStart
-	$(if $(findstring --jobserver,$(MAKEFLAGS)),$(error make -j is not supported, use make JOBS=n))
+	$(if $(findstring jobserver,$(.FEATURES)),,$(error make -j is not supported, use make JOBS=n))
 	$(call CheckEnvironment)
 	@$(PRINTF) $(LOG_INFO) "Running make as '$(MAKE) $(MFLAGS) $(MAKE_ARGS)'\n"
 	@$(PRINTF) "Building $(PRODUCT_NAME) for target '$(call GetRealTarget)' in configuration '$(CONF_NAME)'\n\n"