Remove cast-as-lvalue extension.

	* call.c (build_conditional_expr): Correct formatting.
	(convert_like_real): Use lvalue_p, not non_cast_lvalue_p.
	(initialize_real): Use real_lvalue_p, not real_non_cast_lvalue_p.
	* cp-tree.h (non_cast_lvalue_p): Remove.
	(real_non_cast_lvalue_p): Remove.
	(non_cast_lvalue_or_else): Remove.
	* tree.c (lvalue_p_1): Remove allow_cast_as_lvalue parameter.
	(real_lvalue_p): Adjust call to lvalue_p_1.
	(non_cast_lvalue_p): Remove.
	(non_cast_lvalue_or_else): Remove.
	(lvalue_p): Adjust call to lvalue_p_1.
	(lvalue_or_else): Simplify.
	* typeck.c (build_unary_op): Use lvalue_or_else, not
	non_cast_lvalue_or_else.
	(build_static_cast): Use real_lvalue_p, not real_non_cast_lvalue_p.

	* doc/extend.texi: Document removal of cast-as-lvalue extension in
	C++.

	* g++.dg/expr/lval1.C: New test.
	* g++.dg/ext/lvcast.C: Remove.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@71051 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index acbd799..f078ad4 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2003-09-04  Mark Mitchell  <mark@codesourcery.com>
+
+       * doc/extend.texi: Document removal of cast-as-lvalue extension in
+       C++.
+
 2003-09-04  Nicolas Roche  <roche@act-europe.fr>
 
        * gcc.c (process_command): Fix typo.

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index dafa9c5..50fe265 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,22 @@
+2003-09-04  Mark Mitchell  <mark@codesourcery.com>
+
+       Remove cast-as-lvalue extension.
+       * call.c (build_conditional_expr): Correct formatting.
+       (convert_like_real): Use lvalue_p, not non_cast_lvalue_p.
+       (initialize_real): Use real_lvalue_p, not real_non_cast_lvalue_p.
+       * cp-tree.h (non_cast_lvalue_p): Remove.
+       (real_non_cast_lvalue_p): Remove.
+       (non_cast_lvalue_or_else): Remove.
+       * tree.c (lvalue_p_1): Remove allow_cast_as_lvalue parameter.
+       (real_lvalue_p): Adjust call to lvalue_p_1.
+       (non_cast_lvalue_p): Remove.
+       (non_cast_lvalue_or_else): Remove.
+       (lvalue_p): Adjust call to lvalue_p_1.
+       (lvalue_or_else): Simplify.
+       * typeck.c (build_unary_op): Use lvalue_or_else, not
+       non_cast_lvalue_or_else.
+       (build_static_cast): Use real_lvalue_p, not real_non_cast_lvalue_p.
+
 2003-09-03  DJ Delorie  <dj@redhat.com>
 
        * decl.c (finish_function): Pass fndecl to aggregate_value_p.

diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index 9e46282..35a8226 100644 (file)
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -3193,8 +3193,9 @@ build_conditional_expr (tree arg1, tree arg2, tree arg3)
 
      If the second and third operands are lvalues and have the same
      type, the result is of that type and is an lvalue.  */
-  if (real_lvalue_p (arg2) && real_lvalue_p (arg3) && 
-      same_type_p (arg2_type, arg3_type))
+  if (real_lvalue_p (arg2) 
+      && real_lvalue_p (arg3) 
+      && same_type_p (arg2_type, arg3_type))
     {
       result_type = arg2_type;
       goto valid_operands;
@@ -4126,7 +4127,7 @@ convert_like_real (tree convs, tree expr, tree fn, int argnum, int inner,
        tree ref_type = totype;
 
        /* If necessary, create a temporary.  */
-       if (NEED_TEMPORARY_P (convs) || !non_cast_lvalue_p (expr))
+       if (NEED_TEMPORARY_P (convs) || !lvalue_p (expr))
          {
            tree type = TREE_TYPE (TREE_OPERAND (convs, 0));
 
@@ -6089,7 +6090,7 @@ initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
        base_conv_type = NULL_TREE;
       /* Perform the remainder of the conversion.  */
       expr = convert_like (conv, expr);
-      if (!real_non_cast_lvalue_p (expr))
+      if (!real_lvalue_p (expr))
        {
          tree init;
          tree type;

diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index cf4b8ce..50228e2 100644 (file)
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -4167,10 +4167,7 @@ extern int zero_init_p                           (tree);
 extern tree canonical_type_variant              (tree);
 extern tree copy_base_binfos                   (tree, tree, tree);
 extern int member_p                            (tree);
-extern cp_lvalue_kind real_lvalue_p            (tree);
-extern int non_cast_lvalue_p                   (tree);
-extern cp_lvalue_kind real_non_cast_lvalue_p    (tree);
-extern int non_cast_lvalue_or_else             (tree, const char *);
+extern cp_lvalue_kind real_lvalue_p             (tree);
 extern tree build_min                          (enum tree_code, tree,
                                                         ...);
 extern tree build_min_nt                       (enum tree_code, ...);

diff --git a/gcc/cp/tree.c b/gcc/cp/tree.c
index 532d8b9..71742a7 100644 (file)
--- a/gcc/cp/tree.c
+++ b/gcc/cp/tree.c
@@ -41,7 +41,7 @@ static tree build_cplus_array_type_1 (tree, tree);
 static int list_hash_eq (const void *, const void *);
 static hashval_t list_hash_pieces (tree, tree, tree);
 static hashval_t list_hash (const void *);
-static cp_lvalue_kind lvalue_p_1 (tree, int, int);
+static cp_lvalue_kind lvalue_p_1 (tree, int);
 static tree no_linkage_helper (tree *, int *, void *);
 static tree mark_local_for_remap_r (tree *, int *, void *);
 static tree cp_unsave_r (tree *, int *, void *);
@@ -60,8 +60,7 @@ static tree handle_init_priority_attribute (tree *, tree, tree, int, bool *);
 
 static cp_lvalue_kind
 lvalue_p_1 (tree ref, 
-            int treat_class_rvalues_as_lvalues, 
-            int allow_cast_as_lvalue)
+            int treat_class_rvalues_as_lvalues)
 {
   cp_lvalue_kind op1_lvalue_kind = clk_none;
   cp_lvalue_kind op2_lvalue_kind = clk_none;
@@ -85,21 +84,11 @@ lvalue_p_1 (tree ref,
     case REALPART_EXPR:
     case IMAGPART_EXPR:
       return lvalue_p_1 (TREE_OPERAND (ref, 0),
-                        treat_class_rvalues_as_lvalues,
-                        allow_cast_as_lvalue);
-
-    case NOP_EXPR:
-      if (allow_cast_as_lvalue)
-       return lvalue_p_1 (TREE_OPERAND (ref, 0),
-                          treat_class_rvalues_as_lvalues,
-                          allow_cast_as_lvalue);
-      else
-       return clk_none;
+                        treat_class_rvalues_as_lvalues);
 
     case COMPONENT_REF:
       op1_lvalue_kind = lvalue_p_1 (TREE_OPERAND (ref, 0),
-                                   treat_class_rvalues_as_lvalues,
-                                   allow_cast_as_lvalue);
+                                   treat_class_rvalues_as_lvalues);
       if (!op1_lvalue_kind 
          /* The "field" can be a FUNCTION_DECL or an OVERLOAD in some  
             situations.  */
@@ -140,20 +129,16 @@ lvalue_p_1 (tree ref,
     case MAX_EXPR:
     case MIN_EXPR:
       op1_lvalue_kind = lvalue_p_1 (TREE_OPERAND (ref, 0),
-                                   treat_class_rvalues_as_lvalues,
-                                   allow_cast_as_lvalue);
+                                   treat_class_rvalues_as_lvalues);
       op2_lvalue_kind = lvalue_p_1 (TREE_OPERAND (ref, 1),
-                                   treat_class_rvalues_as_lvalues,
-                                   allow_cast_as_lvalue);
+                                   treat_class_rvalues_as_lvalues);
       break;
 
     case COND_EXPR:
       op1_lvalue_kind = lvalue_p_1 (TREE_OPERAND (ref, 1),
-                                   treat_class_rvalues_as_lvalues,
-                                   allow_cast_as_lvalue);
+                                   treat_class_rvalues_as_lvalues);
       op2_lvalue_kind = lvalue_p_1 (TREE_OPERAND (ref, 2),
-                                   treat_class_rvalues_as_lvalues,
-                                   allow_cast_as_lvalue);
+                                   treat_class_rvalues_as_lvalues);
       break;
 
     case MODIFY_EXPR:
@@ -161,8 +146,7 @@ lvalue_p_1 (tree ref,
 
     case COMPOUND_EXPR:
       return lvalue_p_1 (TREE_OPERAND (ref, 1),
-                        treat_class_rvalues_as_lvalues,
-                        allow_cast_as_lvalue);
+                        treat_class_rvalues_as_lvalues);
 
     case TARGET_EXPR:
       return treat_class_rvalues_as_lvalues ? clk_class : clk_none;
@@ -205,27 +189,15 @@ lvalue_p_1 (tree ref,
   return op1_lvalue_kind;
 }
 
-/* If REF is an lvalue, returns the kind of lvalue that REF is.
-   Otherwise, returns clk_none.  Lvalues can be assigned, unless they
-   have TREE_READONLY, or unless they are FUNCTION_DECLs.  Lvalues can
-   have their address taken, unless they have DECL_REGISTER.  */
-
-cp_lvalue_kind
-real_lvalue_p (tree ref)
-{
-  return lvalue_p_1 (ref, /*treat_class_rvalues_as_lvalues=*/ 0, /*cast*/ 1);
-}
-
 /* Returns the kind of lvalue that REF is, in the sense of
    [basic.lval].  This function should really be named lvalue_p; it
    computes the C++ definition of lvalue.  */
 
 cp_lvalue_kind
-real_non_cast_lvalue_p (tree ref)
+real_lvalue_p (tree ref)
 {
   return lvalue_p_1 (ref, 
-                    /*treat_class_rvalues_as_lvalues=*/0, 
-                    /*allow_cast_as_lvalue=*/0);
+                    /*treat_class_rvalues_as_lvalues=*/0);
 }
 
 /* This differs from real_lvalue_p in that class rvalues are
@@ -235,14 +207,7 @@ int
 lvalue_p (tree ref)
 {
   return 
-    (lvalue_p_1 (ref, /*class rvalue ok*/ 1, /*cast*/ 1) != clk_none);
-}
-
-int
-non_cast_lvalue_p (tree ref)
-{
-  return 
-    (lvalue_p_1 (ref, /*class rvalue ok*/ 1, /*cast*/ 0) != clk_none);
+    (lvalue_p_1 (ref, /*class rvalue ok*/ 1) != clk_none);
 }
 
 /* Return nonzero if REF is an lvalue valid for this language;
@@ -251,21 +216,12 @@ non_cast_lvalue_p (tree ref)
 int
 lvalue_or_else (tree ref, const char* string)
 {
-  int ret = lvalue_p_1 (ref, /* class rvalue ok */ 1, /* cast ok */ 1);
-  int win = (ret != clk_none);
-  if (! win)
-    error ("non-lvalue in %s", string);
-  return win;
-}
-
-int
-non_cast_lvalue_or_else (tree ref, const char* string)
-{
-  int ret = lvalue_p_1 (ref, /* class rvalue ok */ 1, /* cast ok */ 0);
-  int win = (ret != clk_none);
-  if (! win)
-    error ("non-lvalue in %s", string);
-  return win;
+  if (!lvalue_p (ref))
+    {
+      error ("non-lvalue in %s", string);
+      return 0;
+    }
+  return 1;
 }
 
 /* Build a TARGET_EXPR, initializing the DECL with the VALUE.  */

diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index 564b337..2a21a00 100644 (file)
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -3967,7 +3967,7 @@ build_unary_op (enum tree_code code, tree xarg, int noconvert)
         is an error.  */
       else if (TREE_CODE (argtype) != FUNCTION_TYPE
               && TREE_CODE (argtype) != METHOD_TYPE
-              && !non_cast_lvalue_or_else (arg, "unary `&'"))
+              && !lvalue_or_else (arg, "unary `&'"))
        return error_mark_node;
 
       if (argtype != error_mark_node)
@@ -4391,7 +4391,7 @@ build_static_cast (tree type, tree expr)
   if (TREE_CODE (type) == REFERENCE_TYPE
       && CLASS_TYPE_P (TREE_TYPE (type))
       && CLASS_TYPE_P (intype)
-      && real_non_cast_lvalue_p (expr)
+      && real_lvalue_p (expr)
       && DERIVED_FROM_P (intype, TREE_TYPE (type))
       && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
                      build_pointer_type (TYPE_MAIN_VARIANT 

diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index 0edf2cf..6664e1c 100644 (file)
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -1071,9 +1071,9 @@ Compound expressions, conditional expressions and casts are allowed as
 lvalues provided their operands are lvalues.  This means that you can take
 their addresses or store values into them.
 
-Standard C++ allows compound expressions and conditional expressions as
-lvalues, and permits casts to reference type, so use of this extension
-is deprecated for C++ code.
+Standard C++ allows compound expressions and conditional expressions
+as lvalues, and permits casts to reference type, so use of this
+extension is not supported for C++ code.
 
 For example, a compound expression can be assigned, provided the last
 expression in the sequence is an lvalue.  These two expressions are

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index d417f83..562ed09 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2003-09-04  Mark Mitchell  <mark@codesourcery.com>
+
+       * g++.dg/expr/lval1.C: New test.
+       * g++.dg/ext/lvcast.C: Remove.
+
 2003-09-03  Roger Sayle  <roger@eyesopen.com>
 
        PR optimization/11700.

diff --git a/gcc/testsuite/g++.dg/expr/lval1.C b/gcc/testsuite/g++.dg/expr/lval1.C
new file mode 100644 (file)
index 0000000..bed47d8
--- /dev/null
+++ b/gcc/testsuite/g++.dg/expr/lval1.C
@@ -0,0 +1,7 @@
+// Contributed by Matt Austern <austern@apple.com>
+
+void f ()
+{
+  int n;
+  (char) n = 1; // { dg-error "" }
+}

diff --git a/gcc/testsuite/g++.dg/ext/lvcast.C b/gcc/testsuite/g++.dg/ext/lvcast.C
deleted file mode 100644 (file)
index efff04e..0000000
--- a/gcc/testsuite/g++.dg/ext/lvcast.C
+++ /dev/null
@@ -1,11 +0,0 @@
-// Copyright (C) 2002 Free Software Foundation
-// Contributed by Matt Austern <austern@apple.com>
-
-// { dg-do compile }
-// { dg-options -fpermissive }
-
-void f ()
-{
-  int n;
-  (char) n = 1;
-}