diff --git a/sc2/build/unix/build.config b/sc2/build/unix/build.config
index 893ef7e1e..0f5c87159 100644
--- a/sc2/build/unix/build.config
+++ b/sc2/build/unix/build.config
@@ -47,6 +47,9 @@ uqm_requirements()
 	define_have_symbol getopt_long
 	define_have_header regex.h
 
+	# Add define for HAVE__BOOL
+	define_have_type _Bool
+
 	# Add an environment variable for MACRO_WIN32 and MACRO___MINGW32__
 	define_have_macro WIN32
 	define_have_macro __MINGW32__
diff --git a/sc2/src/config_unix.h.in b/sc2/src/config_unix.h.in
index 7c7158939..c8f0480f6 100644
--- a/sc2/src/config_unix.h.in
+++ b/sc2/src/config_unix.h.in
@@ -52,6 +52,8 @@
 /* Defined if your system has wint_t of its own */
 @HAVE_WINT_T@
 
+/* Defined if your system has _Bool of its own */
+@HAVE__BOOL@
+
 #endif  /* _CONFIG_UNIX_H */
 
-
diff --git a/sc2/src/config_win.h.in b/sc2/src/config_win.h.in
index 032c253ed..31d154a9b 100644
--- a/sc2/src/config_win.h.in
+++ b/sc2/src/config_win.h.in
@@ -53,6 +53,9 @@
 /* Defined if your system has wint_t of its own */
 @HAVE_WINT_T@
 
+/* Defined if your system has _Bool of its own */
+@HAVE__BOOL@
+
 #endif  /* _CONFIG_WIN_H */
 
 
diff --git a/sc2/src/sc2code/libs/uio/types.h b/sc2/src/sc2code/libs/uio/types.h
index a30cad9e2..b92f7a4ad 100644
--- a/sc2/src/sc2code/libs/uio/types.h
+++ b/sc2/src/sc2code/libs/uio/types.h
@@ -21,11 +21,33 @@
 #ifndef _uio_TYPES_H
 #define _uio_TYPES_H
 
-typedef enum
-{
-	false = 0,
-	true
-} uio_bool;
+#include "config.h"
+
+// ISO C99 compatible boolean types. The ISO C99 standard defines:
+// - An object declared as type _Bool, large enough to store the values 0
+//   and 1, the rank of which is less than the rank of all other standard
+//   integer types.
+// - A macro "bool", which expands to "_Bool".
+// - A macro "true", which expands to the integer constant 1, suitable for
+//   use in #if preprocessing directives.
+// - A macro "false", which expands to the integer constant 0, suitable for
+//   use in #if preprocessing directives.
+// - A macro "__bool_true_false_are_defined", which expands to the integer
+//   constant 1, suitable for use in #if preprocessing directives.
+#ifndef __bool_true_false_are_defined
+#undef bool
+#undef false
+#undef true
+#ifndef HAVE__BOOL
+typedef unsigned char _Bool;
+#endif  /* HAVE_BOOL */
+#define bool _Bool
+#define true 1
+#define false 0
+#define __bool_true_false_are_defined
+#endif  /* __bool_true_false_are_defined */
+
+typedef bool uio_bool;
 
 typedef unsigned char  uio_uint8;
 typedef   signed char  uio_sint8;