[svn:parrot] r39833 - trunk/include/parrot

[petdance at svn.parrot.org]

Author: petdance
Date: Tue Jun 30 02:59:43 2009
New Revision: 39833
URL: https://trac.parrot.org/parrot/changeset/39833

Log:
annotations on the differences between pure and const functions

Modified:
   trunk/include/parrot/compiler.h

Modified: trunk/include/parrot/compiler.h
==============================================================================
--- trunk/include/parrot/compiler.h	Tue Jun 30 02:41:37 2009	(r39832)
+++ trunk/include/parrot/compiler.h	Tue Jun 30 02:59:43 2009	(r39833)
@@ -126,8 +126,12 @@
 #define PARROT_IGNORABLE_RESULT
 #define PARROT_WARN_UNUSED_RESULT   __attribute__warn_unused_result__
 
+/* Pure functions have no side-effects, and depend only on parms or globals. e.g. strlen() */
 #define PARROT_PURE_FUNCTION                __attribute__pure__  __attribute__warn_unused_result__
+
+/* Const functions are pure functions, and do not examine targets of pointers. e.g. sqrt() */
 #define PARROT_CONST_FUNCTION               __attribute__const__ __attribute__warn_unused_result__
+
 #define PARROT_DOES_NOT_RETURN              /*@noreturn@*/ __attribute__noreturn__
 #define PARROT_DOES_NOT_RETURN_WHEN_FALSE   /*@noreturnwhenfalse@*/
 #define PARROT_MALLOC                       /*@only@*/ __attribute__malloc__ __attribute__warn_unused_result__