diff --git a/make/defs.mk b/make/defs.mk
index d852ffc6..5ced6810 100644
--- a/make/defs.mk
+++ b/make/defs.mk
@@ -974,7 +974,14 @@ ifeq ($(STRIP_SYMBOLS),true)
 	STRIP_DONE  ?= strip.done
 endif
 
-INCLUDE                   += $(LOCAL_INCLUDE) -I.
+INCLUDE                   += $(LOCAL_INCLUDE)
+
+# force use of double quotes, allow header namespaces
+ifeq ($(HDRDIR_SCOPE_SUFFIX),)
+  INCLUDE                 += -I.
+else
+  INCLUDE                 += -iquote .
+endif
 
 ifeq ($(USE_PROJECT_LIB),true)
 INCLUDE                   += $(PROJECT_INCLUDE) -I$(TOPDIR)/include