diff --git a/src/files.cpp b/src/files.cpp
index 981b351a9..d7dad642e 100644
--- a/src/files.cpp
+++ b/src/files.cpp
@@ -33,7 +33,9 @@
 **
 */
 
+#ifdef _WIN32
 #define USE_WINDOWS_DWORD
+#endif
 #include "LzmaDec.h"
 
 #include "files.h"
diff --git a/src/resourcefiles/file_7z.cpp b/src/resourcefiles/file_7z.cpp
index c3845d8cc..72e8d5f0e 100644
--- a/src/resourcefiles/file_7z.cpp
+++ b/src/resourcefiles/file_7z.cpp
@@ -32,7 +32,9 @@
 **
 **
 */
+#ifdef _WIN32
 #define USE_WINDOWS_DWORD
+#endif
 
 #include "7z.h"
 #include "7zCrc.h"