diff --git a/make/defs.mk b/make/defs.mk
index 96e996a7..b12fece3 100644
--- a/make/defs.mk
+++ b/make/defs.mk
@@ -273,10 +273,16 @@ SUBDIRS_TO_ITERATE     = $(filter-out $(IGNORE_SUBDIRS),$(SUBDIRS))
 
 # compiler and linker
 # gcc
-GCC_VERSION            = $(shell  gcc -v 2>&1 | grep "gcc version" | awk '{ print $$3;}')
-GCC_MAJOR              = $(shell  gcc -v 2>&1 | grep "gcc version" | awk '{ split($$3,a,"."); print a[1];}')
-GCC_MINOR              = $(shell  gcc -v 2>&1 | grep "gcc version" | awk '{ split($$3,a,"."); print a[2];}')
-GCC_REV                = $(shell  gcc -v 2>&1 | grep "gcc version" | awk '{ split($$3,a,"."); print a[3];}')
+GCC_VERSION           := $(shell  gcc -v 2>&1 | grep "gcc version" | awk '{ print $$3;}')
+GCC_MAJOR             := $(shell  gcc -v 2>&1 | grep "gcc version" | awk '{ split($$3,a,"."); print a[1];}')
+GCC_MINOR             := $(shell  gcc -v 2>&1 | grep "gcc version" | awk '{ split($$3,a,"."); print a[2];}')
+GCC_REV               := $(shell  gcc -v 2>&1 | grep "gcc version" | awk '{ split($$3,a,"."); print a[3];}')
+
+LD_VERSION            := $(shell ld -V | $(SED) '/GNU ld/ !d; s/(.*)//; s/[^0-9.-]*//')
+LD_MAJOR              := $(shell echo $(LD_VERSION) | cut -d. -f1)
+LD_MINOR              := $(shell echo $(LD_VERSION) | cut -d. -f2)
+LD_REV                := $(shell echo $(LD_VERSION) | cut -d. -f3)
+UPDATE_REPO_SH        := /opt/packager-server/bin/packager-server schedule-rebuild
 
 # clang
 CLANG_CPPFLAGS            += -Wno-unused-private-field -Wno-self-assign-field -Wno-overloaded-virtual
@@ -289,11 +295,15 @@ BUILD_CPPFLAGS        += -std=c++11
 endif
 endif
 
-LD_VERSION             = $(shell ld -V | $(SED) '/GNU ld/ !d; s/(.*)//; s/[^0-9.-]*//')
-LD_MAJOR               = $(shell echo $(LD_VERSION) | cut -d. -f1)
-LD_MINOR               = $(shell echo $(LD_VERSION) | cut -d. -f2)
-LD_REV                 = $(shell echo $(LD_VERSION) | cut -d. -f3)
-UPDATE_REPO_SH         = /opt/packager-server/bin/packager-server schedule-rebuild
+ifeq ($(shell test $(GCC_MAJOR) -ge 5; echo $$?),0)
+  ifeq ($(USE_CPP_FORCE_OVERRIDE),true)
+    GCC_CPPFLAGS     += -Werror=suggest-override
+  endif
+endif
+
+ifeq ($(USE_CPP_WARN_INCONSISTENT_OVERRIDE),true)
+  CLANG_CPPFLAGS   += -Winconsistent-missing-override
+endif
 
 # -- target files and dirs