diff --git a/tests/test_context_cloning.c b/tests/test_context_cloning.c
index 0805c55..9087fca 100644
--- a/tests/test_context_cloning.c
+++ b/tests/test_context_cloning.c
@@ -1,6 +1,7 @@
 // Tests that evaluation works after the context was cloned.
 #include <stdlib.h>
 #include <stdio.h>
+#include <string.h>
 
 #include <rwkv.h>
 
diff --git a/tests/test_logit_calculation_skipping.c b/tests/test_logit_calculation_skipping.c
index 7e42b4f..2765a19 100644
--- a/tests/test_logit_calculation_skipping.c
+++ b/tests/test_logit_calculation_skipping.c
@@ -1,6 +1,7 @@
 // Tests that evaluation works when the logits parameter was set to NULL.
 #include <stdlib.h>
 #include <stdio.h>
+#include <string.h>
 
 #include <rwkv.h>