X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/ad7871609881e73855d0b04da49b486cd93efca7..ed554bc5e4201344d7eaad78263566e79428759c:/usr/src/sys/sys/cdefs.h

diff --git a/usr/src/sys/sys/cdefs.h b/usr/src/sys/sys/cdefs.h
index a04665e30e..c104b9e964 100644
--- a/usr/src/sys/sys/cdefs.h
+++ b/usr/src/sys/sys/cdefs.h
@@ -2,6 +2,9 @@
  * Copyright (c) 1991, 1993
  *	The Regents of the University of California.  All rights reserved.
  *
+ * This code is derived from software contributed to Berkeley by
+ * Berkeley Software Design, Inc.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
@@ -30,7 +33,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	@(#)cdefs.h	8.1 (Berkeley) 6/2/93
+ *	@(#)cdefs.h	8.7 (Berkeley) 1/21/94
  */
 
 #ifndef	_CDEFS_H_
@@ -56,39 +59,64 @@
 #define	__CONCAT(x,y)	x ## y
 #define	__STRING(x)	#x
 
+#define	__const		const		/* define reserved names to standard */
+#define	__signed	signed
+#define	__volatile	volatile
+#if defined(__cplusplus)
+#define	__inline	inline		/* convert to C++ keyword */
+#else
+#ifndef __GNUC__
+#define	__inline			/* delete GCC keyword */
+#endif /* !__GNUC__ */
+#endif /* !__cplusplus */
+
 #else	/* !(__STDC__ || __cplusplus) */
 #define	__P(protos)	()		/* traditional C preprocessor */
 #define	__CONCAT(x,y)	x/**/y
 #define	__STRING(x)	"x"
 
-#ifdef __GNUC__
-#define	const		__const		/* GCC: ANSI C with -traditional */
-#define	inline		__inline
-#define	signed		__signed
-#define	volatile	__volatile
-
-#else	/* !__GNUC__ */
+#ifndef __GNUC__
+#define	__const				/* delete pseudo-ANSI C keywords */
+#define	__inline
+#define	__signed
+#define	__volatile
+/*
+ * In non-ANSI C environments, new programs will want ANSI-only C keywords
+ * deleted from the program and old programs will want them left alone.
+ * When using a compiler other than gcc, programs using the ANSI C keywords
+ * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
+ * When using "gcc -traditional", we assume that this is the intent; if
+ * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
+ */
+#ifndef	NO_ANSI_KEYWORDS
 #define	const				/* delete ANSI C keywords */
 #define	inline
 #define	signed
 #define	volatile
+#endif
 #endif	/* !__GNUC__ */
 #endif	/* !(__STDC__ || __cplusplus) */
 
 /*
- * GCC has extensions for declaring functions as `pure' (always returns
- * the same value given the same inputs, i.e., has no external state and
- * no side effects) and `dead' (nonreturning).  These mainly affect
- * optimization and warnings.  Unfortunately, GCC complains if these are
- * used under strict ANSI mode (`gcc -ansi -pedantic'), hence we need to
- * define them only if compiling without this.
+ * GCC1 and some versions of GCC2 declare dead (non-returning) and
+ * pure (no side effects) functions using "volatile" and "const";
+ * unfortunately, these then cause warnings under "-ansi -pedantic".
+ * GCC2 uses a new, peculiar __attribute__((attrs)) style.  All of
+ * these work for GNU C++ (modulo a slight glitch in the C++ grammar
+ * in the distribution version of 2.5.5).
  */
+#if !defined(__GNUC__) || __GNUC__ < 2 || __GNUC_MINOR__ < 5
+#define	__attribute__(x)	/* delete __attribute__ if non-gcc or gcc1 */
 #if defined(__GNUC__) && !defined(__STRICT_ANSI__)
-#define __dead __volatile
-#define __pure __const
-#else
-#define __dead
-#define __pure
+#define	__dead		__volatile
+#define	__pure		__const
+#endif
+#endif
+
+/* Delete pseudo-keywords wherever they are not available or needed. */
+#ifndef __dead
+#define	__dead
+#define	__pure
 #endif
 
 #endif /* !_CDEFS_H_ */