diff --git a/util.c b/util.c
index cc7cd8e..e6e9a0b 100644
--- a/util.c
+++ b/util.c
@@ -9,7 +9,7 @@
 #endif
 
 void sleep_secs(double secs) {
-#ifdef WIN32
+#if defined(_WIN32) || defined(WIN32)
 	Sleep(secs * 1000.0);
 #else
 	struct timespec ts;
diff --git a/util.h b/util.h
index 195334b..98dda62 100644
--- a/util.h
+++ b/util.h
@@ -7,7 +7,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-#ifdef WIN32
+#if defined(_WIN32) || defined(WIN32)
 #include <windows.h> /* SSIZE_T */
 typedef SSIZE_T ssize_t;
 #else