diff --git a/libs/fst/00_PATCH_win_io.patch b/libs/fst/00_PATCH_win_io.patch
new file mode 100644
index 000000000..5813758cd
--- /dev/null
+++ b/libs/fst/00_PATCH_win_io.patch
@@ -0,0 +1,11 @@
+--- fst_win_unistd.h
++++ fst_win_unistd.h
+@@ -26,7 +26,7 @@
+ #define WIN_UNISTD_H
+ 
+ #include <stdlib.h>
+-#ifdef _WIN64
++#if defined(_MSC_VER)
+ #include <io.h>
+ #else
+ #include <sys/io.h>
diff --git a/libs/fst/00_UPDATE.sh b/libs/fst/00_UPDATE.sh
index f7066076f..aef0e4fe8 100755
--- a/libs/fst/00_UPDATE.sh
+++ b/libs/fst/00_UPDATE.sh
@@ -16,3 +16,4 @@ sed -i -e 's,<config.h>,"config.h",' *.cc *.h
 sed -i -e 's,"fastlz.c","fastlz.cc",' *.cc *.h
 
 patch -p0 < 00_PATCH_win_zlib.patch
+patch -p0 < 00_PATCH_win_io.patch
diff --git a/libs/fst/fst_win_unistd.h b/libs/fst/fst_win_unistd.h
index 15ab2c1fc..089f0180b 100644
--- a/libs/fst/fst_win_unistd.h
+++ b/libs/fst/fst_win_unistd.h
@@ -26,7 +26,7 @@
 #define WIN_UNISTD_H
 
 #include <stdlib.h>
-#ifdef _WIN64
+#if defined(_MSC_VER)
 #include <io.h>
 #else
 #include <sys/io.h>