diff --git a/make/defs.mk b/make/defs.mk
index 001dedef..f3df6a23 100644
--- a/make/defs.mk
+++ b/make/defs.mk
@@ -290,7 +290,7 @@ SRC_HEADERED          += $(shell if [ "$(LOCAL_SRC)" ]; then grep -ic "it servic
 SRC_UNHEADERED        += $(filter-out $(SRC_HEADERED),$(LOCAL_SRC))
 LOCAL_C               ?= $(wildcard *.c)
 LOCAL_CPP             ?= $(wildcard *.cc *.cpp *.C)
-LOCAL_H               ?= $(wildcard *.h *.H)
+LOCAL_H               ?= $(wildcard *.h *.H *.hpp)
 SFILES                ?= $(wildcard *.S)
 #PREREQ_H              += $(foreach dir,$(PREREQ_DIR),$(wildcard $(dir)/*.h))
 ALL_H                 += $(LOCAL_H) $(PREREQ_H)
@@ -354,7 +354,7 @@ INSTALLED_SYSCFG      ?= $(addprefix $(INSTALL_SYSCFGDIR)/,$(SYSCFG_FILES))
 INSTALLATION_FILE_TYPES += HDR
 BUILD_HDRDIR_BASE     ?= $(TOPDIR)/include
 BUILD_HDRDIR          ?= $(BUILD_HDRDIR_BASE)/$(HDRDIR_SCOPE_SUFFIX)
-SRC_H                 += $(filter %.h %.H, $(SRC_ALL_CPP))
+SRC_H                 += $(filter %.h %.H %.hpp, $(SRC_ALL_CPP))
 BUILD_H                = $(addprefix $(BUILD_HDRDIR)/,$(SRC_H))
 BUILD_HDR              = $(addprefix $(BUILD_HDRDIR)/,$(SRC_H))
 INSTALL_HDRDIR        ?= $(PREFIX)/include