diff --git a/Makefile b/Makefile
index 4f3a723..5e9b11d 100644
--- a/Makefile
+++ b/Makefile
@@ -347,6 +347,11 @@
 BUILD_OPTIONS  += $(call ignore_implicit,USE_REGPARM)
 endif
 
+# report DLMALLOC_SRC only if explicitly specified
+ifneq ($(DLMALLOC_SRC),)
+BUILD_OPTIONS += DLMALLOC_SRC=$(DLMALLOC_SRC)
+endif
+
 ifneq ($(USE_DLMALLOC),)
 BUILD_OPTIONS  += $(call ignore_implicit,USE_DLMALLOC)
 ifeq ($(DLMALLOC_SRC),)
@@ -355,10 +360,9 @@
 endif
 
 ifneq ($(DLMALLOC_SRC),)
-# May be changed to match PAGE_SIZE on every platform
+# DLMALLOC_THRES may be changed to match PAGE_SIZE on every platform
 DLMALLOC_THRES = 4096
 OPTIONS_OBJS  += src/dlmalloc.o
-BUILD_OPTIONS += DLMALLOC_SRC=$(DLMALLOC_SRC)
 endif
 
 ifneq ($(USE_PCRE),)