diff --git a/googletest/src/gtest-port.cc b/googletest/src/gtest-port.cc
index c2ea6d76e..0162fac44 100644
--- a/googletest/src/gtest-port.cc
+++ b/googletest/src/gtest-port.cc
@@ -60,6 +60,7 @@
 
 #if GTEST_OS_AIX
 # include <procinfo.h>
+# include <sys/types.h>
 #endif  // GTEST_OS_AIX
 
 #include "gtest/gtest-spi.h"