diff --git a/make/plugin-defs.mk b/make/plugin-defs.mk
index e2015aed..239e49a8 100644
--- a/make/plugin-defs.mk
+++ b/make/plugin-defs.mk
@@ -10,7 +10,11 @@ else
 PLUGIN_SUFFIX                  ?= dll
 endif
 
-PLUGIN_PREFIX_AND_API          = $(PLUGIN_PREFIX)_$(PLUGIN_API)
+ifneq ($(PLUGIN_PREFIX),)
+PLUGIN_PREFIX_                  = $(PLUGIN_PREFIX)_
+endif
+
+PLUGIN_PREFIX_AND_API          ?= $(PLUGIN_PREFIX_)$(PLUGIN_API)
 PLUGIN                         ?= $(PLUGIN_PREFIX_AND_API)_$(PLUGIN_NAME).$(PLUGIN_SUFFIX)
 
 CFLAGS                         += -D PLUGIN_NAME_STR=\"$(PLUGIN_NAME)\"