PR c/10675

        * c-decl.c: Include hashtab.h.
        (detect_field_duplicates): New.
        (finish_struct): Use it.
        * Makefile.in (c-decl.o): Update.
        * c-parse.in (structsp_attr): Nreverse component_decl_list results.
        (component_decl_list, component_decl_list2,
        components, components_notype): Build list in reverse order.
        (enumlist): Clarify docs.  Use TREE_CHAIN not chainon.
        * tree.c (chainon): Special case op2 null as well.
        Reorg for clarity.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@66710 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 26 insertions, 14 deletions

diff --git a/gcc/c-parse.in b/gcc/c-parse.in
index f9d3656662d..a9400b39d8f 100644
--- a/gcc/c-parse.in
+++ b/gcc/c-parse.in
@@ -1,4 +1,4 @@
- /* YACC parser for C syntax and for Objective C.  -*-c-*-
+/* YACC parser for C syntax and for Objective C.  -*-c-*-
    Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996,
    1997, 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
 
@@ -1759,18 +1759,20 @@ structsp_attr:
 		  /* Start scope of tag before parsing components.  */
 		}
 	  component_decl_list '}' maybe_attribute
-		{ $$ = finish_struct ($<ttype>4, $5, chainon ($1, $7)); }
+		{ $$ = finish_struct ($<ttype>4, nreverse ($5),
+				      chainon ($1, $7)); }
 	| struct_head '{' component_decl_list '}' maybe_attribute
 		{ $$ = finish_struct (start_struct (RECORD_TYPE, NULL_TREE),
-				      $3, chainon ($1, $5));
+				      nreverse ($3), chainon ($1, $5));
 		}
 	| union_head identifier '{'
 		{ $$ = start_struct (UNION_TYPE, $2); }
 	  component_decl_list '}' maybe_attribute
-		{ $$ = finish_struct ($<ttype>4, $5, chainon ($1, $7)); }
+		{ $$ = finish_struct ($<ttype>4, nreverse ($5),
+				      chainon ($1, $7)); }
 	| union_head '{' component_decl_list '}' maybe_attribute
 		{ $$ = finish_struct (start_struct (UNION_TYPE, NULL_TREE),
-				      $3, chainon ($1, $5));
+				      nreverse ($3), chainon ($1, $5));
 		}
 	| enum_head identifier '{'
 		{ $$ = start_enum ($2); }
@@ -1809,18 +1811,30 @@ maybecomma_warn:
 		    pedwarn ("comma at end of enumerator list"); }
 	;
 
+/* We chain the components in reverse order.  They are put in forward
+   order in structsp_attr.
+
+   Note that component_declarator returns single decls, so components
+   and components_notype can use TREE_CHAIN directly, wheras components
+   and components_notype return lists (of comma separated decls), so
+   component_decl_list and component_decl_list2 must use chainon.
+
+   The theory behind all this is that there will be more semicolon
+   separated fields than comma separated fields, and so we'll be
+   minimizing the number of node traversals required by chainon.  */
+
 component_decl_list:
 	  component_decl_list2
 		{ $$ = $1; }
 	| component_decl_list2 component_decl
-		{ $$ = chainon ($1, $2);
+		{ $$ = chainon ($2, $1);
 		  pedwarn ("no semicolon at end of struct or union"); }
 	;
 
 component_decl_list2:	/* empty */
 		{ $$ = NULL_TREE; }
 	| component_decl_list2 component_decl ';'
-		{ $$ = chainon ($1, $2); }
+		{ $$ = chainon ($2, $1); }
 	| component_decl_list2 ';'
 		{ if (pedantic)
 		    pedwarn ("extra semicolon in struct or union specified"); }
@@ -1831,7 +1845,7 @@ ifobjc
 		  tree interface = lookup_interface ($3);
 
 		  if (interface)
-		    $$ = get_class_ivars (interface);
+		    $$ = nreverse (get_class_ivars (interface));
 		  else
 		    {
 		      error ("cannot find interface declaration for `%s'",
@@ -1874,13 +1888,13 @@ component_decl:
 components:
 	  component_declarator
 	| components ',' maybe_resetattrs component_declarator
-		{ $$ = chainon ($1, $4); }
+		{ TREE_CHAIN ($4) = $1; $$ = $4; }
 	;
 
 components_notype:
 	  component_notype_declarator
 	| components_notype ',' maybe_resetattrs component_notype_declarator
-		{ $$ = chainon ($1, $4); }
+		{ TREE_CHAIN ($4) = $1; $$ = $4; }
 	;
 
 component_declarator:
@@ -1910,9 +1924,7 @@ component_notype_declarator:
 	;
 
 /* We chain the enumerators in reverse order.
-   They are put in forward order where enumlist is used.
-   (The order used to be significant, but no longer is so.
-   However, we still maintain the order, just to be clean.)  */
+   They are put in forward order in structsp_attr.  */
 
 enumlist:
 	  enumerator
@@ -1920,7 +1932,7 @@ enumlist:
 		{ if ($1 == error_mark_node)
 		    $$ = $1;
 		  else
-		    $$ = chainon ($3, $1); }
+		    TREE_CHAIN ($3) = $1, $$ = $3; }
 	| error
 		{ $$ = error_mark_node; }
 	;