diff --git a/src/allocators.h b/src/allocators.h
index cdea66dd38..fa9534bc52 100644
--- a/src/allocators.h
+++ b/src/allocators.h
@@ -5,6 +5,7 @@
 #ifndef BITCOIN_ALLOCATORS_H
 #define BITCOIN_ALLOCATORS_H
 
+#include <string.h>
 #include <string>
 
 #ifdef WIN32
diff --git a/src/uint256.h b/src/uint256.h
index 104b84970a..9966a14ed7 100644
--- a/src/uint256.h
+++ b/src/uint256.h
@@ -6,6 +6,7 @@
 #define BITCOIN_UINT256_H
 
 #include <limits.h>
+#include <stdio.h>
 #include <string.h>
 #include <string>
 #include <vector>