foc: suppress gcc warnings of L4Re components

Ref #2405

repos/base-foc/lib/mk/kernel-foc.inc

@@ -43,6 +43,13 @@ PKGS := l4re-core/crtn \
 
 L4_BUILD_DIR := $(LIB_CACHE_DIR)/syscall-foc/build
 
+#
+# Supress several warnings especially of the uclibc-minimal
+#
+WARNINGS += -Wno-cpp -Wno-nonnull-compare -Wno-shift-overflow \
+            -Wno-unused-but-set-variable -Wno-maybe-uninitialized \
+            -Wno-unused-value -Wno-deprecated-declarations -Wno-attributes
+
 include $(REP_DIR)/lib/mk/l4_pkg.inc
 
 #

repos/base-foc/lib/mk/l4_pkg.inc

@@ -52,6 +52,6 @@ endif
 %.tag:
 	$(VERBOSE_MK) set -o pipefail; \
 	              $(MAKE) $(VERBOSE_DIR) O=$(L4_BUILD_DIR) -C $(L4_PKG_DIR)/$* \
-	                      "$(L4_BUILD_OPT)" $(BUILD_OUTPUT_FILTER)
+	                      "$(L4_BUILD_OPT)" WARNINGS=$(WARNINGS) $(BUILD_OUTPUT_FILTER)
 	$(VERBOSE)mkdir -p $(dir $@) && touch $@