warn against K&R compiler in glibc 2.2

[Andreas Jaeger <aj at suse dot de>]

PR libc/1607 titled "sys/cdefs.h's __REDIRECT relies upon ANSI-ism"
lead me to look at this issue.

IMO we should warn the user that a K&R compiler is not supported with
glibc 2.2.

The easiest way is AFAIK to add the following to some file:
#ifndef __STDC__
# error "You need a ISO C conforming compiler to use the glibc headers"
#endif

What do you think?  I'm in favour of adding this to sys/cdefs.h and
remove all K&R support stuff from that file.  A patch is appended.

Andreas

2000-03-30  Andreas Jaeger  <aj@suse.de>

	* misc/sys/cdefs.h: Remove K&R support, error out if compiled by
	an K&R compiler.

============================================================
Index: misc/sys/cdefs.h
--- misc/sys/cdefs.h	1999/12/19 08:31:26	1.30
+++ misc/sys/cdefs.h	2000/03/30 13:41:20
@@ -1,4 +1,4 @@
-/* Copyright (C) 1992,93,94,95,96,97,98,99 Free Software Foundation, Inc.
+/* Copyright (C) 1992,93,94,95,96,97,98,99,2000 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -28,6 +28,12 @@
 #undef	__P
 #undef	__PMT
 
+/* The GNU C library can only be used by a ISO C compiler (conformant
+   to ISO C90 or ISO C99). gcc -traditional is not ISO c conformant.  */
+#ifndef __STDC__
+# error "You need a ISO C conforming compiler to use the glibc headers"
+#endif
+
 #ifdef __GNUC__
 
 /* GCC can always grok prototypes.  For C++ programs we add throw()
@@ -46,18 +52,9 @@
 #else	/* Not GCC.  */
 
 # define __inline		/* No inline functions.  */
-
-# if (defined __STDC__ && __STDC__) || defined __cplusplus
-
-#  define __P(args)	args
-#  define __PMT(args)	args
 
-# else	/* Not ANSI C or C++.  */
-
-#  define __P(args)	()	/* No prototypes.  */
-#  define __PMT(args)	()
-
-# endif	/* ANSI C or C++.  */
+# define __P(args)	args
+# define __PMT(args)	args
 
 # define __const	const
 # define __signed	signed
@@ -65,37 +62,13 @@
 
 #endif	/* GCC.  */
 
-/* For these things, GCC behaves the ANSI way normally,
-   and the non-ANSI way under -traditional.  */
+#define __CONCAT(x,y)	x ## y
+#define __STRING(x)	#x
 
-#if defined __STDC__ && __STDC__
-
-# define __CONCAT(x,y)	x ## y
-# define __STRING(x)	#x
-
 /* This is not a typedef so `const __ptr_t' does the right thing.  */
-# define __ptr_t void *
-# define __long_double_t  long double
-
-#else
-
-# define __CONCAT(x,y)	x/**/y
-# define __STRING(x)	"x"
-
-# define __ptr_t char *
-# define __long_double_t  long double
-
-/* The BSD header files use the ANSI keywords unmodified (this means that
-   old programs may lose if they use the new keywords as identifiers), but
-   those names are not available under -traditional.  We define them to
-   their __ versions, which are taken care of above.  */
-# ifdef	__USE_BSD
-#  define const		__const
-#  define signed		__signed
-#  define volatile	__volatile
-# endif
+#define __ptr_t void *
+#define __long_double_t  long double
 
-#endif	/* __STDC__ */
 
 
 /* C++ needs to know that types and declarations are C, not C++.  */

-- 
 Andreas Jaeger
  SuSE Labs aj@suse.de
   private aj@arthur.rhein-neckar.de