From: Paul Eggert Date: Wed, 29 Aug 2012 14:52:32 +0000 (-0700) Subject: stdbool: be more compatible with mixed C/C++ compiles X-Git-Tag: v0.1~460 X-Git-Url: http://erislabs.net/gitweb/?a=commitdiff_plain;h=8a73c1c5c8b04143c6583f2413cc46b0035a3384;p=gnulib.git stdbool: be more compatible with mixed C/C++ compiles * lib/stdbool.in.h (_Bool, true, false) [__cplusplus]: Define to bool, true, false, respectively, as GCC's builtin stdbool.h does. Problem reported by Michael Goffioul in . --- diff --git a/ChangeLog b/ChangeLog index 63f651f0a..f484d28b7 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,11 @@ +2012-08-29 Paul Eggert + + stdbool: be more compatible with mixed C/C++ compiles + * lib/stdbool.in.h (_Bool, true, false) [__cplusplus]: + Define to bool, true, false, respectively, as GCC's builtin + stdbool.h does. Problem reported by Michael Goffioul in + . + 2012-08-28 Jim Meyering revert last change: it was not needed diff --git a/lib/stdbool.in.h b/lib/stdbool.in.h index e58f211d8..924c8ff00 100644 --- a/lib/stdbool.in.h +++ b/lib/stdbool.in.h @@ -66,24 +66,18 @@ # undef true #endif -/* For the sake of symbolic names in gdb, we define true and false as - enum constants, not only as macros. - It is tempting to write - typedef enum { false = 0, true = 1 } _Bool; - so that gdb prints values of type 'bool' symbolically. But if we do - this, values of type '_Bool' may promote to 'int' or 'unsigned int' - (see ISO C 99 6.7.2.2.(4)); however, '_Bool' must promote to 'int' - (see ISO C 99 6.3.1.1.(2)). So we add a negative value to the - enum; this ensures that '_Bool' promotes to 'int'. */ -#if defined __cplusplus || (defined __BEOS__ && !defined __HAIKU__) +#ifdef __cplusplus +# define _Bool bool +#else +# if defined __BEOS__ && !defined __HAIKU__ /* A compiler known to have 'bool'. */ /* If the compiler already has both 'bool' and '_Bool', we can assume they are the same types. */ -# if !@HAVE__BOOL@ +# if !@HAVE__BOOL@ typedef bool _Bool; -# endif -#else -# if !defined __GNUC__ +# endif +# else +# if !defined __GNUC__ /* If @HAVE__BOOL@: Some HP-UX cc and AIX IBM C compiler versions have compiler bugs when the built-in _Bool type is used. See @@ -103,19 +97,35 @@ typedef bool _Bool; "Invalid enumerator. (badenum)" with HP-UX cc on Tru64. The only benefit of the enum, debuggability, is not important with these compilers. So use 'signed char' and no enum. */ -# define _Bool signed char -# else +# define _Bool signed char +# else /* With this compiler, trust the _Bool type if the compiler has it. */ -# if !@HAVE__BOOL@ +# if !@HAVE__BOOL@ + /* For the sake of symbolic names in gdb, define true and false as + enum constants, not only as macros. + It is tempting to write + typedef enum { false = 0, true = 1 } _Bool; + so that gdb prints values of type 'bool' symbolically. But then + values of type '_Bool' might promote to 'int' or 'unsigned int' + (see ISO C 99 6.7.2.2.(4)); however, '_Bool' must promote to 'int' + (see ISO C 99 6.3.1.1.(2)). So add a negative value to the + enum; this ensures that '_Bool' promotes to 'int'. */ typedef enum { _Bool_must_promote_to_int = -1, false = 0, true = 1 } _Bool; +# endif # endif # endif #endif #define bool _Bool /* The other macros must be usable in preprocessor directives. */ -#define false 0 -#define true 1 +#ifdef __cplusplus +# define false false +# define true true +#else +# define false 0 +# define true 1 +#endif + #define __bool_true_false_are_defined 1 #endif /* _GL_STDBOOL_H */