On 23 Nov 2021 15:09, Richard Earnshaw wrote:
> This is wrong and breaks all old versions of C++.

this is a bit vague.  it would help if you provided details as to what broke.
i doubt this broke all old versions of C++ everywhere.

i'm guessing you're referring to the GNU C++ (libstdc++) library specifically
and its hardcoding of newlib's internal ctype define names.
https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=libstdc%2B%2B-v3/config/os/newlib/ctype_base.h;hb=releases/gcc-11.2.0

if you're talking about something else, please state so clearly.

> The GNU sim code should not be using reserved names (those starting _) 
> in normal source code.  Such names are reserved to the implementation.

that's not really a good reason to go pooping all over the namespace.

we can maintain backwards compat here for C++ code fairly easily:

--- a/newlib/libc/include/ctype.h
+++ b/newlib/libc/include/ctype.h
@@ -71,6 +71,16 @@ enum
 
 /* For C++ backward-compatibility only.  */
 extern	__IMPORT const char	_ctype_[];
+#ifdef __cplusplus
+# define _U _ISupper
+# define _L _ISlower
+# define _N _ISdigit
+# define _S _ISspace
+# define _P _ISpunct
+# define _C _IScntrl
+# define _X _ISxdigit
+# define _B _ISblank
+#endif
 
 #ifdef __HAVE_LOCALE_INFO__
 const char *__locale_ctype_ptr (void);

considering the numerical value is part of the ABI, not the name, libstdc++
could have inlined the constant values instead.  i wonder how long of a version
skew is reasonable if we wanted to transition it to the new names to match what
glibc uses.
-mike