# undef true
#endif
-/* For the sake of symbolic names in gdb, define _Bool as an enum type. */
+/* For the sake of symbolic names in gdb, define true and false as
+ enum constants. However, do not define _Bool as the enum type,
+ since the enum type might be compatible with unsigned int, whereas
+ _Bool must promote to int. */
#ifndef __cplusplus
# if !@HAVE__BOOL@
-typedef enum { false = 0, true = 1 } _Bool;
+enum { false = 0, true = 1 };
+typedef signed char _Bool;
# endif
#else
typedef bool _Bool;