diff --git a/addons/51degrees/dummy/v4hash/hash/hash.c b/addons/51degrees/dummy/v4hash/hash/hash.c
index 96e56050d9..e9a739ed45 100644
--- a/addons/51degrees/dummy/v4hash/hash/hash.c
+++ b/addons/51degrees/dummy/v4hash/hash/hash.c
@@ -36,6 +36,9 @@
 static fiftyoneDegreesHeaders dummyHeaders = { };
 static fiftyoneDegreesDataSetBase dummyDataSet = { &dummyHeaders };
 
+fiftyoneDegreesConfigHash fiftyoneDegreesHashInMemoryConfig;
+fiftyoneDegreesPropertiesRequired fiftyoneDegreesPropertiesDefault;
+
 fiftyoneDegreesDataSetBase* fiftyoneDegreesDataSetGet(
 	fiftyoneDegreesResourceManager *manager) {
 	return &dummyDataSet;
diff --git a/addons/51degrees/dummy/v4hash/hash/hash.h b/addons/51degrees/dummy/v4hash/hash/hash.h
index d899f6a382..5d04d17662 100644
--- a/addons/51degrees/dummy/v4hash/hash/hash.h
+++ b/addons/51degrees/dummy/v4hash/hash/hash.h
@@ -189,7 +189,7 @@ typedef struct fiftyone_degrees_config_hash_t {
 	bool usePredictiveGraph;
 } fiftyoneDegreesConfigHash;
 
-fiftyoneDegreesConfigHash fiftyoneDegreesHashInMemoryConfig;
+extern fiftyoneDegreesConfigHash fiftyoneDegreesHashInMemoryConfig;
 
 typedef struct fiftyone_degrees_property_available_t {
 
@@ -206,7 +206,7 @@ typedef struct fiftyone_degrees_properties_required_t {
 	fiftyoneDegreesPropertiesAvailable *existing;
 } fiftyoneDegreesPropertiesRequired;
 
-fiftyoneDegreesPropertiesRequired fiftyoneDegreesPropertiesDefault;
+extern fiftyoneDegreesPropertiesRequired fiftyoneDegreesPropertiesDefault;
 
 typedef struct fiftyone_degrees_memory_reader_t {
 	byte *startByte;