diff --git a/src/processor/dump_context.cc b/src/processor/dump_context.cc
index 54bf231e..5f7d5682 100644
--- a/src/processor/dump_context.cc
+++ b/src/processor/dump_context.cc
@@ -36,6 +36,16 @@
 #include <assert.h>
 #include <stdio.h>
 
+#ifdef _WIN32
+#include <io.h>
+#define PRIx64 "llx"
+#define PRIx32 "lx"
+#define snprintf _snprintf
+#else  // _WIN32
+#include <unistd.h>
+#define O_BINARY 0
+#endif  // _WIN32
+
 #include "processor/logging.h"
 
 namespace google_breakpad {