diff --git a/spine-cpp/spine-cpp/src/spine/Extension.cpp b/spine-cpp/spine-cpp/src/spine/Extension.cpp
index 81c667104..5cfe0b3ab 100644
--- a/spine-cpp/spine-cpp/src/spine/Extension.cpp
+++ b/spine-cpp/spine-cpp/src/spine/Extension.cpp
@@ -32,6 +32,7 @@
 
 #include <fstream>
 #include <assert.h>
+#include <cstring>
 
 namespace Spine
 {
diff --git a/spine-cpp/spine-cpp/src/spine/SkeletonBinary.cpp b/spine-cpp/spine-cpp/src/spine/SkeletonBinary.cpp
index 5cbd1b5ef..16c44cee2 100644
--- a/spine-cpp/spine-cpp/src/spine/SkeletonBinary.cpp
+++ b/spine-cpp/spine-cpp/src/spine/SkeletonBinary.cpp
@@ -78,6 +78,8 @@
 #include <spine/Event.h>
 #include <spine/Vertices.h>
 
+#include <cstring>
+
 namespace Spine
 {
     const int SkeletonBinary::BONE_ROTATE = 0;
diff --git a/spine-cpp/spine-cpp/src/spine/SkeletonJson.cpp b/spine-cpp/spine-cpp/src/spine/SkeletonJson.cpp
index b24d48513..2642e069d 100644
--- a/spine-cpp/spine-cpp/src/spine/SkeletonJson.cpp
+++ b/spine-cpp/spine-cpp/src/spine/SkeletonJson.cpp
@@ -79,6 +79,8 @@
 #include <spine/Event.h>
 #include <spine/Vertices.h>
 
+#include <cstring>
+
 #if defined(WIN32) || defined(_WIN32) || defined(__WIN32) && !defined(__CYGWIN__)
 #define strdup _strdup
 #endif