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From-SVN: r2094

gcc/c-tree.h

@@ -27,19 +27,30 @@ struct lang_identifier
 };
 
 /* Macros for access to language-specific slots in an identifier.  */
+/* Each of these slots contains a DECL node or null.  */
 
+/* This represents the value which the identifier has in the
+   file-scope namespace.  */
 #define IDENTIFIER_GLOBAL_VALUE(NODE)	\
   (((struct lang_identifier *)(NODE))->global_value)
+/* This represents the value which the identifier has in the current
+   scope.  */
 #define IDENTIFIER_LOCAL_VALUE(NODE)	\
   (((struct lang_identifier *)(NODE))->local_value)
+/* This represents the value which the identifier has as a label in
+   the current label scope.  */
 #define IDENTIFIER_LABEL_VALUE(NODE)	\
   (((struct lang_identifier *)(NODE))->label_value)
-/* IDENTIFIER_LIMBO_VALUE records the extern decl of this identifier,
-   if it has had one.  */
+/* This records the extern decl of this identifier, if it has had one
+   at any point in this compilation.  */
 #define IDENTIFIER_LIMBO_VALUE(NODE)	\
   (((struct lang_identifier *)(NODE))->limbo_value)
+/* This records the implicit function decl of this identifier, if it
+   has had one at any point in this compilation.  */
 #define IDENTIFIER_IMPLICIT_DECL(NODE)	\
   (((struct lang_identifier *)(NODE))->implicit_decl)
+/* This is the last function in which we printed an "undefined variable"
+   message for this identifier.  Value is a FUNCTION_DECL or null.  */
 #define IDENTIFIER_ERROR_LOCUS(NODE)	\
   (((struct lang_identifier *)(NODE))->error_locus)