/* Language-level data type conversion for GNU C++.
Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+ 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+ Free Software Foundation, Inc.
Hacked by Michael Tiemann (tiemann@cygnus.com)
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
+the Free Software Foundation; either version 3, or (at your option)
any later version.
GCC is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to
-the Free Software Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
/* This file contains the functions for converting C++ expressions
#include "convert.h"
#include "toplev.h"
#include "decl.h"
+#include "target.h"
-static tree cp_convert_to_pointer (tree, tree, bool);
+static tree cp_convert_to_pointer (tree, tree);
static tree convert_to_pointer_force (tree, tree);
+static tree build_type_conversion (tree, tree);
static tree build_up_reference (tree, tree, int, tree);
static void warn_ref_binding (tree, tree, tree);
narrowing is always done with a NOP_EXPR:
In convert.c, convert_to_integer.
In c-typeck.c, build_binary_op_nodefault (boolean ops),
- and c_common_truthvalue_conversion.
+ and c_common_truthvalue_conversion.
In expr.c: expand_expr, for operands of a MULT_EXPR.
In fold-const.c: fold.
In tree.c: get_narrower and get_unwidened.
else if dealing with method pointers, delegate
else convert blindly
else if converting class, pass off to build_type_conversion
- else try C-style pointer conversion. If FORCE is true then allow
- conversions via virtual bases (these are permitted by reinterpret_cast,
- but not static_cast). */
+ else try C-style pointer conversion. */
static tree
-cp_convert_to_pointer (tree type, tree expr, bool force)
+cp_convert_to_pointer (tree type, tree expr)
{
tree intype = TREE_TYPE (expr);
enum tree_code form;
tree rval;
+ if (intype == error_mark_node)
+ return error_mark_node;
- if (IS_AGGR_TYPE (intype))
+ if (MAYBE_CLASS_TYPE_P (intype))
{
intype = complete_type (intype);
if (!COMPLETE_TYPE_P (intype))
{
- error ("can't convert from incomplete type `%T' to `%T'",
- intype, type);
+ error ("can't convert from incomplete type %qT to %qT",
+ intype, type);
return error_mark_node;
}
if (rval)
{
if (rval == error_mark_node)
- error ("conversion of `%E' from `%T' to `%T' is ambiguous",
- expr, intype, type);
+ error ("conversion of %qE from %qT to %qT is ambiguous",
+ expr, intype, type);
return rval;
}
}
&& (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
|| VOID_TYPE_P (TREE_TYPE (type))))
{
- /* Allow an implicit this pointer for pointer to member
- functions. */
- if (TYPE_PTRMEMFUNC_P (intype))
- {
- if (pedantic || warn_pmf2ptr)
- pedwarn ("converting from `%T' to `%T'", intype, type);
- if (TREE_CODE (expr) == PTRMEM_CST)
- expr = build_address (PTRMEM_CST_MEMBER (expr));
- else
- {
- tree decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype),
- 0);
- decl = build_address (decl);
- expr = get_member_function_from_ptrfunc (&decl, expr);
- }
- }
- else if (TREE_CODE (TREE_TYPE (expr)) == METHOD_TYPE)
- {
- if (pedantic || warn_pmf2ptr)
- pedwarn ("converting from `%T' to `%T'", intype, type);
- expr = build_addr_func (expr);
- }
+ if (TYPE_PTRMEMFUNC_P (intype)
+ || TREE_CODE (intype) == METHOD_TYPE)
+ return convert_member_func_to_ptr (type, expr);
if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
return build_nop (type, expr);
intype = TREE_TYPE (expr);
if (TYPE_MAIN_VARIANT (type) != intype
&& TREE_CODE (type) == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (type)) == RECORD_TYPE
- && IS_AGGR_TYPE (TREE_TYPE (type))
- && IS_AGGR_TYPE (TREE_TYPE (intype))
+ && MAYBE_CLASS_TYPE_P (TREE_TYPE (type))
+ && MAYBE_CLASS_TYPE_P (TREE_TYPE (intype))
&& TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE)
{
enum tree_code code = PLUS_EXPR;
intype_class = TREE_TYPE (intype);
type_class = TREE_TYPE (type);
- same_p = same_type_p (TYPE_MAIN_VARIANT (intype_class),
+ same_p = same_type_p (TYPE_MAIN_VARIANT (intype_class),
TYPE_MAIN_VARIANT (type_class));
binfo = NULL_TREE;
/* Try derived to base conversion. */
if (TYPE_PTRMEMFUNC_P (type))
{
- error ("cannot convert `%E' from type `%T' to type `%T'",
- expr, intype, type);
+ error ("cannot convert %qE from type %qT to type %qT",
+ expr, intype, type);
return error_mark_node;
}
return build_nop (type, expr);
}
- else if (TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
- {
- tree b1;
- tree b2;
- tree binfo;
- enum tree_code code = PLUS_EXPR;
- base_kind bk;
-
- b1 = TYPE_PTRMEM_CLASS_TYPE (type);
- b2 = TYPE_PTRMEM_CLASS_TYPE (intype);
- binfo = lookup_base (b1, b2, ba_check, &bk);
- if (!binfo)
- {
- binfo = lookup_base (b2, b1, ba_check, &bk);
- code = MINUS_EXPR;
- }
- if (binfo == error_mark_node)
- return error_mark_node;
-
- if (bk == bk_via_virtual)
- {
- if (force)
- warning ("pointer to member cast from `%T' to `%T' is via virtual base",
- intype, type);
- else
- {
- error ("pointer to member cast from `%T' to `%T' is via virtual base",
- intype, type);
- return error_mark_node;
- }
- /* This is a reinterpret cast, whose result is unspecified.
- We choose to do nothing. */
- return build1 (NOP_EXPR, type, expr);
- }
-
- if (TREE_CODE (expr) == PTRMEM_CST)
- expr = cplus_expand_constant (expr);
-
- if (binfo && !integer_zerop (BINFO_OFFSET (binfo)))
- expr = size_binop (code,
- build_nop (sizetype, expr),
- BINFO_OFFSET (binfo));
- return build_nop (type, expr);
- }
- else if (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype))
- return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr, 0);
+ else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
+ || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
+ return convert_ptrmem (type, expr, /*allow_inverse_p=*/false,
+ /*c_cast_p=*/false);
else if (TYPE_PTRMEMFUNC_P (intype))
{
if (!warn_pmf2ptr)
{
if (TREE_CODE (expr) == PTRMEM_CST)
return cp_convert_to_pointer (type,
- PTRMEM_CST_MEMBER (expr),
- force);
+ PTRMEM_CST_MEMBER (expr));
else if (TREE_CODE (expr) == OFFSET_REF)
{
tree object = TREE_OPERAND (expr, 0);
TREE_OPERAND (expr, 1));
}
}
- error ("cannot convert `%E' from type `%T' to type `%T'",
- expr, intype, type);
+ error ("cannot convert %qE from type %qT to type %qT",
+ expr, intype, type);
return error_mark_node;
}
if (integer_zerop (expr))
{
if (TYPE_PTRMEMFUNC_P (type))
- return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr, 0);
+ return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr, 0,
+ /*c_cast_p=*/false);
if (TYPE_PTRMEM_P (type))
{
/* A NULL pointer-to-member is represented by -1, not by
zero. */
- expr = build_int_cst (type, -1);
- /* Fix up the representation of -1 if appropriate. */
- expr = force_fit_type (expr, 0, false, false);
+ expr = build_int_cst_type (type, -1);
}
else
expr = build_int_cst (type, 0);
-
+
return expr;
}
else if (TYPE_PTR_TO_MEMBER_P (type) && INTEGRAL_CODE_P (form))
{
- error ("invalid conversion from '%T' to '%T'", intype, type);
+ error ("invalid conversion from %qT to %qT", intype, type);
return error_mark_node;
}
if (TYPE_PRECISION (intype) == POINTER_SIZE)
return build1 (CONVERT_EXPR, type, expr);
expr = cp_convert (c_common_type_for_size (POINTER_SIZE, 0), expr);
- /* Modes may be different but sizes should be the same. */
- if (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (expr)))
- != GET_MODE_SIZE (TYPE_MODE (type)))
- /* There is supposed to be some integral type
- that is the same width as a pointer. */
- abort ();
+ /* Modes may be different but sizes should be the same. There
+ is supposed to be some integral type that is the same width
+ as a pointer. */
+ gcc_assert (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (expr)))
+ == GET_MODE_SIZE (TYPE_MODE (type)));
+
return convert_to_pointer (type, expr);
}
if (type_unknown_p (expr))
- return instantiate_type (type, expr, tf_error | tf_warning);
+ return instantiate_type (type, expr, tf_warning_or_error);
- error ("cannot convert `%E' from type `%T' to type `%T'",
- expr, intype, type);
+ error ("cannot convert %qE from type %qT to type %qT",
+ expr, intype, type);
return error_mark_node;
}
{
tree intype = TREE_TYPE (expr);
enum tree_code form = TREE_CODE (intype);
-
+
if (form == POINTER_TYPE)
{
intype = TYPE_MAIN_VARIANT (intype);
if (TYPE_MAIN_VARIANT (type) != intype
&& TREE_CODE (TREE_TYPE (type)) == RECORD_TYPE
- && IS_AGGR_TYPE (TREE_TYPE (type))
- && IS_AGGR_TYPE (TREE_TYPE (intype))
+ && MAYBE_CLASS_TYPE_P (TREE_TYPE (type))
+ && MAYBE_CLASS_TYPE_P (TREE_TYPE (intype))
&& TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE)
{
enum tree_code code = PLUS_EXPR;
tree binfo;
binfo = lookup_base (TREE_TYPE (intype), TREE_TYPE (type),
- ba_ignore, NULL);
+ ba_unique, NULL);
if (!binfo)
{
binfo = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
- ba_ignore, NULL);
+ ba_unique, NULL);
code = MINUS_EXPR;
}
if (binfo == error_mark_node)
if (binfo)
{
expr = build_base_path (code, expr, binfo, 0);
- if (expr == error_mark_node)
- return error_mark_node;
+ if (expr == error_mark_node)
+ return error_mark_node;
/* Add any qualifier conversions. */
if (!same_type_p (TREE_TYPE (TREE_TYPE (expr)),
TREE_TYPE (type)))
}
}
- return cp_convert_to_pointer (type, expr, true);
+ return cp_convert_to_pointer (type, expr);
}
/* We are passing something to a function which requires a reference.
/* Process the initializer for the declaration. */
DECL_INITIAL (arg) = targ;
- cp_finish_decl (arg, targ, NULL_TREE,
+ cp_finish_decl (arg, targ, /*init_const_expr_p=*/false, NULL_TREE,
LOOKUP_ONLYCONVERTING|DIRECT_BIND);
}
else if (!(flags & DIRECT_BIND) && ! lvalue_p (arg))
/* If we had a way to wrap this up, and say, if we ever needed its
address, transform all occurrences of the register, into a memory
reference we could win better. */
- rval = build_unary_op (ADDR_EXPR, arg, 1);
+ rval = cp_build_unary_op (ADDR_EXPR, arg, 1, tf_warning_or_error);
if (rval == error_mark_node)
return error_mark_node;
if ((flags & LOOKUP_PROTECT)
&& TYPE_MAIN_VARIANT (argtype) != TYPE_MAIN_VARIANT (target_type)
- && IS_AGGR_TYPE (argtype)
- && IS_AGGR_TYPE (target_type))
+ && MAYBE_CLASS_TYPE_P (argtype)
+ && MAYBE_CLASS_TYPE_P (target_type))
{
/* We go through lookup_base for the access control. */
tree binfo = lookup_base (argtype, target_type, ba_check, NULL);
/* Subroutine of convert_to_reference. REFTYPE is the target reference type.
INTYPE is the original rvalue type and DECL is an optional _DECL node
for diagnostics.
-
+
[dcl.init.ref] says that if an rvalue is used to
initialize a reference, then the reference must be to a
non-volatile const type. */
warn_ref_binding (tree reftype, tree intype, tree decl)
{
tree ttl = TREE_TYPE (reftype);
-
+
if (!CP_TYPE_CONST_NON_VOLATILE_P (ttl))
{
const char *msg;
if (CP_TYPE_VOLATILE_P (ttl) && decl)
- msg = "initialization of volatile reference type `%#T' from rvalue of type `%T'";
+ msg = "initialization of volatile reference type %q#T from"
+ " rvalue of type %qT";
else if (CP_TYPE_VOLATILE_P (ttl))
- msg = "conversion to volatile reference type `%#T' from rvalue of type `%T'";
+ msg = "conversion to volatile reference type %q#T "
+ " from rvalue of type %qT";
else if (decl)
- msg = "initialization of non-const reference type `%#T' from rvalue of type `%T'";
+ msg = "initialization of non-const reference type %q#T from"
+ " rvalue of type %qT";
else
- msg = "conversion to non-const reference type `%#T' from rvalue of type `%T'";
+ msg = "conversion to non-const reference type %q#T from"
+ " rvalue of type %qT";
- pedwarn (msg, reftype, intype);
+ permerror (input_location, msg, reftype, intype);
}
}
tree
convert_to_reference (tree reftype, tree expr, int convtype,
- int flags, tree decl)
+ int flags, tree decl)
{
tree type = TYPE_MAIN_VARIANT (TREE_TYPE (reftype));
tree intype;
tree rval_as_conversion = NULL_TREE;
bool can_convert_intype_to_type;
- if (TREE_CODE (type) == FUNCTION_TYPE
+ if (TREE_CODE (type) == FUNCTION_TYPE
&& TREE_TYPE (expr) == unknown_type_node)
- expr = instantiate_type (type, expr,
+ expr = instantiate_type (type, expr,
(flags & LOOKUP_COMPLAIN)
- ? tf_error | tf_warning : tf_none);
- else
- expr = convert_from_reference (expr);
+ ? tf_warning_or_error : tf_none);
if (expr == error_mark_node)
return error_mark_node;
intype = TREE_TYPE (expr);
gcc_assert (TREE_CODE (intype) != REFERENCE_TYPE);
+ gcc_assert (TREE_CODE (reftype) == REFERENCE_TYPE);
intype = TYPE_MAIN_VARIANT (intype);
can_convert_intype_to_type = can_convert (type, intype);
if (!can_convert_intype_to_type
- && (convtype & CONV_IMPLICIT) && IS_AGGR_TYPE (intype)
+ && (convtype & CONV_IMPLICIT) && MAYBE_CLASS_TYPE_P (intype)
&& ! (flags & LOOKUP_NO_CONVERSION))
{
/* Look for a user-defined conversion to lvalue that we can use. */
if (! real_lvalue_p (expr))
warn_ref_binding (reftype, intype, decl);
-
+
if (! (convtype & CONV_CONST)
&& !at_least_as_qualified_p (ttl, ttr))
- pedwarn ("conversion from `%T' to `%T' discards qualifiers",
- ttr, reftype);
+ permerror (input_location, "conversion from %qT to %qT discards qualifiers",
+ ttr, reftype);
}
return build_up_reference (reftype, expr, flags, decl);
should be done directly (jason). (int &)ri ---> *(int*)&ri */
/* B* bp; A& ar = (A&)bp; is valid, but it's probably not what they
- meant. */
+ meant. */
if (TREE_CODE (intype) == POINTER_TYPE
&& (comptypes (TREE_TYPE (intype), type,
COMPARE_BASE | COMPARE_DERIVED)))
- warning ("casting `%T' to `%T' does not dereference pointer",
+ warning (0, "casting %qT to %qT does not dereference pointer",
intype, reftype);
-
- rval = build_unary_op (ADDR_EXPR, expr, 0);
+
+ rval = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
if (rval != error_mark_node)
rval = convert_force (build_pointer_type (TREE_TYPE (reftype)),
rval, 0);
else
{
rval = convert_for_initialization (NULL_TREE, type, expr, flags,
- "converting", 0, 0);
+ "converting", 0, 0,
+ tf_warning_or_error);
if (rval == NULL_TREE || rval == error_mark_node)
return rval;
warn_ref_binding (reftype, intype, decl);
}
if (flags & LOOKUP_COMPLAIN)
- error ("cannot convert type `%T' to type `%T'", intype, reftype);
+ error ("cannot convert type %qT to type %qT", intype, reftype);
return error_mark_node;
}
tree
convert_from_reference (tree val)
{
- if (TREE_CODE (TREE_TYPE (val)) == REFERENCE_TYPE)
- return build_indirect_ref (val, NULL);
- return val;
-}
-
-/* Implicitly convert the lvalue EXPR to another lvalue of type TOTYPE,
- preserving cv-qualification. */
+ if (TREE_TYPE (val)
+ && TREE_CODE (TREE_TYPE (val)) == REFERENCE_TYPE)
+ {
+ tree t = TREE_TYPE (TREE_TYPE (val));
+ tree ref = build1 (INDIRECT_REF, t, val);
+
+ /* We *must* set TREE_READONLY when dereferencing a pointer to const,
+ so that we get the proper error message if the result is used
+ to assign to. Also, &* is supposed to be a no-op. */
+ TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
+ TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
+ TREE_SIDE_EFFECTS (ref)
+ = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (val));
+ REFERENCE_REF_P (ref) = 1;
+ val = ref;
+ }
-tree
-convert_lvalue (tree totype, tree expr)
-{
- totype = cp_build_qualified_type (totype, TYPE_QUALS (TREE_TYPE (expr)));
- totype = build_reference_type (totype);
- expr = convert_to_reference (totype, expr, CONV_IMPLICIT, LOOKUP_NORMAL,
- NULL_TREE);
- return convert_from_reference (expr);
+ return val;
}
/* Really perform an lvalue-to-rvalue conversion, including copying an
tree
force_rvalue (tree expr)
{
- if (IS_AGGR_TYPE (TREE_TYPE (expr)) && TREE_CODE (expr) != TARGET_EXPR)
+ if (MAYBE_CLASS_TYPE_P (TREE_TYPE (expr)) && TREE_CODE (expr) != TARGET_EXPR)
expr = ocp_convert (TREE_TYPE (expr), expr,
CONV_IMPLICIT|CONV_FORCE_TEMP, LOOKUP_NORMAL);
else
return expr;
}
+
\f
+/* Fold away simple conversions, but make sure the result is an rvalue. */
+
+tree
+cp_fold_convert (tree type, tree expr)
+{
+ return rvalue (fold_convert (type, expr));
+}
+
/* C++ conversions, preference to static cast conversions. */
tree
return ocp_convert (type, expr, CONV_OLD_CONVERT, LOOKUP_NORMAL);
}
+/* C++ equivalent of convert_and_check but using cp_convert as the
+ conversion function.
+
+ Convert EXPR to TYPE, warning about conversion problems with constants.
+ Invoke this function on every expression that is converted implicitly,
+ i.e. because of language rules and not because of an explicit cast. */
+
+tree
+cp_convert_and_check (tree type, tree expr)
+{
+ tree result;
+
+ if (TREE_TYPE (expr) == type)
+ return expr;
+
+ result = cp_convert (type, expr);
+
+ if (c_inhibit_evaluation_warnings == 0
+ && !TREE_OVERFLOW_P (expr)
+ && result != error_mark_node)
+ warnings_for_convert_and_check (type, expr, result);
+
+ return result;
+}
+
/* Conversion...
FLAGS indicates how we should behave. */
{
tree e = expr;
enum tree_code code = TREE_CODE (type);
+ const char *invalid_conv_diag;
+ tree e1;
if (error_operand_p (e) || type == error_mark_node)
return error_mark_node;
complete_type (type);
complete_type (TREE_TYPE (expr));
- e = decl_constant_value (e);
+ if ((invalid_conv_diag
+ = targetm.invalid_conversion (TREE_TYPE (expr), type)))
+ {
+ error (invalid_conv_diag);
+ return error_mark_node;
+ }
+
+ e = integral_constant_value (e);
- if (IS_AGGR_TYPE (type) && (convtype & CONV_FORCE_TEMP)
- /* Some internal structures (vtable_entry_type, sigtbl_ptr_type)
- don't go through finish_struct, so they don't have the synthesized
- constructors. So don't force a temporary. */
- && TYPE_HAS_CONSTRUCTOR (type))
+ if (MAYBE_CLASS_TYPE_P (type) && (convtype & CONV_FORCE_TEMP))
/* We need a new temporary; don't take this shortcut. */;
- else if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (TREE_TYPE (e)))
+ else if (same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (e)))
{
if (same_type_p (type, TREE_TYPE (e)))
/* The call to fold will not always remove the NOP_EXPR as
convert, which will call ocp_convert, etc. */
return e;
/* For complex data types, we need to perform componentwise
- conversion. */
+ conversion. */
else if (TREE_CODE (type) == COMPLEX_TYPE)
- return fold (convert_to_complex (type, e));
+ return fold_if_not_in_template (convert_to_complex (type, e));
else if (TREE_CODE (e) == TARGET_EXPR)
{
/* Don't build a NOP_EXPR of class type. Instead, change the
- type of the temporary. Only allow this for cv-qual changes,
- though. */
- if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (e)),
- TYPE_MAIN_VARIANT (type)))
- abort ();
+ type of the temporary. */
TREE_TYPE (e) = TREE_TYPE (TARGET_EXPR_SLOT (e)) = type;
return e;
}
- else if (TREE_ADDRESSABLE (type))
- /* We shouldn't be treating objects of ADDRESSABLE type as rvalues. */
- abort ();
else
- return fold (build1 (NOP_EXPR, type, e));
+ {
+ /* We shouldn't be treating objects of ADDRESSABLE type as
+ rvalues. */
+ gcc_assert (!TREE_ADDRESSABLE (type));
+ return fold_if_not_in_template (build_nop (type, e));
+ }
}
+ e1 = targetm.convert_to_type (type, e);
+ if (e1)
+ return e1;
+
if (code == VOID_TYPE && (convtype & CONV_STATIC))
{
- e = convert_to_void (e, /*implicit=*/NULL);
+ e = convert_to_void (e, /*implicit=*/NULL, tf_warning_or_error);
return e;
}
if (INTEGRAL_CODE_P (code))
{
tree intype = TREE_TYPE (e);
- /* enum = enum, enum = int, enum = float, (enum)pointer are all
- errors. */
- if (TREE_CODE (type) == ENUMERAL_TYPE
- && ((ARITHMETIC_TYPE_P (intype) && ! (convtype & CONV_STATIC))
- || (TREE_CODE (intype) == POINTER_TYPE)))
+
+ if (TREE_CODE (type) == ENUMERAL_TYPE)
{
- pedwarn ("conversion from `%#T' to `%#T'", intype, type);
+ /* enum = enum, enum = int, enum = float, (enum)pointer are all
+ errors. */
+ if (((INTEGRAL_OR_ENUMERATION_TYPE_P (intype)
+ || TREE_CODE (intype) == REAL_TYPE)
+ && ! (convtype & CONV_STATIC))
+ || TREE_CODE (intype) == POINTER_TYPE)
+ {
+ if (flags & LOOKUP_COMPLAIN)
+ permerror (input_location, "conversion from %q#T to %q#T", intype, type);
- if (flag_pedantic_errors)
- return error_mark_node;
+ if (!flag_permissive)
+ return error_mark_node;
+ }
+
+ /* [expr.static.cast]
+
+ 8. A value of integral or enumeration type can be explicitly
+ converted to an enumeration type. The value is unchanged if
+ the original value is within the range of the enumeration
+ values. Otherwise, the resulting enumeration value is
+ unspecified. */
+ if (TREE_CODE (expr) == INTEGER_CST && !int_fits_type_p (expr, type))
+ warning (OPT_Wconversion,
+ "the result of the conversion is unspecified because "
+ "%qE is outside the range of type %qT",
+ expr, type);
}
- if (IS_AGGR_TYPE (intype))
+ if (MAYBE_CLASS_TYPE_P (intype))
{
tree rval;
rval = build_type_conversion (type, e);
if (rval)
return rval;
if (flags & LOOKUP_COMPLAIN)
- error ("`%#T' used where a `%T' was expected", intype, type);
+ error ("%q#T used where a %qT was expected", intype, type);
return error_mark_node;
}
if (code == BOOLEAN_TYPE)
return cp_truthvalue_conversion (e);
- return fold (convert_to_integer (type, e));
+ return fold_if_not_in_template (convert_to_integer (type, e));
}
if (POINTER_TYPE_P (type) || TYPE_PTR_TO_MEMBER_P (type))
- return fold (cp_convert_to_pointer (type, e, false));
+ return fold_if_not_in_template (cp_convert_to_pointer (type, e));
if (code == VECTOR_TYPE)
- return fold (convert_to_vector (type, e));
+ {
+ tree in_vtype = TREE_TYPE (e);
+ if (MAYBE_CLASS_TYPE_P (in_vtype))
+ {
+ tree ret_val;
+ ret_val = build_type_conversion (type, e);
+ if (ret_val)
+ return ret_val;
+ if (flags & LOOKUP_COMPLAIN)
+ error ("%q#T used where a %qT was expected", in_vtype, type);
+ return error_mark_node;
+ }
+ return fold_if_not_in_template (convert_to_vector (type, e));
+ }
if (code == REAL_TYPE || code == COMPLEX_TYPE)
{
- if (IS_AGGR_TYPE (TREE_TYPE (e)))
+ if (MAYBE_CLASS_TYPE_P (TREE_TYPE (e)))
{
tree rval;
rval = build_type_conversion (type, e);
return rval;
else
if (flags & LOOKUP_COMPLAIN)
- error ("`%#T' used where a floating point value was expected",
+ error ("%q#T used where a floating point value was expected",
TREE_TYPE (e));
}
if (code == REAL_TYPE)
- return fold (convert_to_real (type, e));
+ return fold_if_not_in_template (convert_to_real (type, e));
else if (code == COMPLEX_TYPE)
- return fold (convert_to_complex (type, e));
+ return fold_if_not_in_template (convert_to_complex (type, e));
}
/* New C++ semantics: since assignment is now based on
memberwise copying, if the rhs type is derived from the
lhs type, then we may still do a conversion. */
- if (IS_AGGR_TYPE_CODE (code))
+ if (RECORD_OR_UNION_CODE_P (code))
{
tree dtype = TREE_TYPE (e);
tree ctor = NULL_TREE;
if (abstract_virtuals_error (NULL_TREE, type))
return error_mark_node;
- if ((flags & LOOKUP_ONLYCONVERTING)
- && ! (IS_AGGR_TYPE (dtype) && DERIVED_FROM_P (type, dtype)))
+ if (BRACE_ENCLOSED_INITIALIZER_P (ctor))
+ ctor = perform_implicit_conversion (type, ctor, tf_warning_or_error);
+ else if ((flags & LOOKUP_ONLYCONVERTING)
+ && ! (CLASS_TYPE_P (dtype) && DERIVED_FROM_P (type, dtype)))
/* For copy-initialization, first we create a temp of the proper type
with a user-defined conversion sequence, then we direct-initialize
the target with the temp (see [dcl.init]). */
ctor = build_user_type_conversion (type, ctor, flags);
else
- ctor = build_special_member_call (NULL_TREE,
- complete_ctor_identifier,
- build_tree_list (NULL_TREE, ctor),
- type, flags);
+ {
+ VEC(tree,gc) *ctor_vec = make_tree_vector_single (ctor);
+ ctor = build_special_member_call (NULL_TREE,
+ complete_ctor_identifier,
+ &ctor_vec,
+ type, flags,
+ tf_warning_or_error);
+ release_tree_vector (ctor_vec);
+ }
if (ctor)
return build_cplus_new (type, ctor);
}
if (flags & LOOKUP_COMPLAIN)
- error ("conversion from `%T' to non-scalar type `%T' requested",
- TREE_TYPE (expr), type);
+ {
+ /* If the conversion failed and expr was an invalid use of pointer to
+ member function, try to report a meaningful error. */
+ if (invalid_nonstatic_memfn_p (expr, tf_warning_or_error))
+ /* We displayed the error message. */;
+ else
+ error ("conversion from %qT to non-scalar type %qT requested",
+ TREE_TYPE (expr), type);
+ }
return error_mark_node;
}
volatile references we do not do this interpretation, because that would
make it impossible to ignore the reference return value from functions. We
issue warnings in the confusing cases.
-
- IMPLICIT is tells us the context of an implicit void conversion. */
+
+ IMPLICIT is non-NULL iff an expression is being implicitly converted; it
+ is NULL when the user is explicitly converting an expression to void via
+ a cast. When non-NULL, IMPLICIT is a string indicating the context of
+ the implicit conversion. */
tree
-convert_to_void (tree expr, const char *implicit)
+convert_to_void (tree expr, const char *implicit, tsubst_flags_t complain)
{
- if (expr == error_mark_node
+ if (expr == error_mark_node
|| TREE_TYPE (expr) == error_mark_node)
return error_mark_node;
if (!TREE_TYPE (expr))
return expr;
- if (invalid_nonstatic_memfn_p (expr))
+ if (invalid_nonstatic_memfn_p (expr, complain))
return error_mark_node;
+ if (TREE_CODE (expr) == PSEUDO_DTOR_EXPR)
+ {
+ if (complain & tf_error)
+ error ("pseudo-destructor is not called");
+ return error_mark_node;
+ }
if (VOID_TYPE_P (TREE_TYPE (expr)))
return expr;
switch (TREE_CODE (expr))
{
case COND_EXPR:
{
- /* The two parts of a cond expr might be separate lvalues. */
- tree op1 = TREE_OPERAND (expr,1);
- tree op2 = TREE_OPERAND (expr,2);
- tree new_op1 = convert_to_void
- (op1, (implicit && !TREE_SIDE_EFFECTS (op2)
- ? "second operand of conditional" : NULL));
- tree new_op2 = convert_to_void
- (op2, (implicit && !TREE_SIDE_EFFECTS (op1)
- ? "third operand of conditional" : NULL));
-
+ /* The two parts of a cond expr might be separate lvalues. */
+ tree op1 = TREE_OPERAND (expr,1);
+ tree op2 = TREE_OPERAND (expr,2);
+ bool side_effects = TREE_SIDE_EFFECTS (op1) || TREE_SIDE_EFFECTS (op2);
+ tree new_op1 = convert_to_void
+ (op1, (implicit && !side_effects
+ ? "second operand of conditional" : NULL), complain);
+ tree new_op2 = convert_to_void
+ (op2, (implicit && !side_effects
+ ? "third operand of conditional" : NULL), complain);
+
expr = build3 (COND_EXPR, TREE_TYPE (new_op1),
TREE_OPERAND (expr, 0), new_op1, new_op2);
- break;
+ break;
}
-
+
case COMPOUND_EXPR:
{
- /* The second part of a compound expr contains the value. */
- tree op1 = TREE_OPERAND (expr,1);
- tree new_op1 = convert_to_void
+ /* The second part of a compound expr contains the value. */
+ tree op1 = TREE_OPERAND (expr,1);
+ tree new_op1 = convert_to_void
(op1, (implicit && !TREE_NO_WARNING (expr)
- ? "right-hand operand of comma" : NULL));
-
- if (new_op1 != op1)
+ ? "right-hand operand of comma" : NULL), complain);
+
+ if (new_op1 != op1)
{
tree t = build2 (COMPOUND_EXPR, TREE_TYPE (new_op1),
TREE_OPERAND (expr, 0), new_op1);
expr = t;
}
- break;
+ break;
}
-
+
case NON_LVALUE_EXPR:
case NOP_EXPR:
/* These have already decayed to rvalue. */
break;
-
+
case CALL_EXPR: /* We have a special meaning for volatile void fn(). */
break;
-
+
case INDIRECT_REF:
{
- tree type = TREE_TYPE (expr);
- int is_reference = TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0)))
- == REFERENCE_TYPE;
- int is_volatile = TYPE_VOLATILE (type);
- int is_complete = COMPLETE_TYPE_P (complete_type (type));
-
- if (is_volatile && !is_complete)
- warning ("object of incomplete type `%T' will not be accessed in %s",
- type, implicit ? implicit : "void context");
- else if (is_reference && is_volatile)
- warning ("object of type `%T' will not be accessed in %s",
- TREE_TYPE (TREE_OPERAND (expr, 0)),
- implicit ? implicit : "void context");
- if (is_reference || !is_volatile || !is_complete)
- expr = TREE_OPERAND (expr, 0);
-
- break;
+ tree type = TREE_TYPE (expr);
+ int is_reference = TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0)))
+ == REFERENCE_TYPE;
+ int is_volatile = TYPE_VOLATILE (type);
+ int is_complete = COMPLETE_TYPE_P (complete_type (type));
+
+ /* Can't load the value if we don't know the type. */
+ if (is_volatile && !is_complete)
+ {
+ if (complain & tf_warning)
+ warning (0, "object of incomplete type %qT will not be accessed in %s",
+ type, implicit ? implicit : "void context");
+ }
+ /* Don't load the value if this is an implicit dereference, or if
+ the type needs to be handled by ctors/dtors. */
+ else if (is_volatile && (is_reference || TREE_ADDRESSABLE (type)))
+ {
+ if (complain & tf_warning)
+ warning (0, "object of type %qT will not be accessed in %s",
+ TREE_TYPE (TREE_OPERAND (expr, 0)),
+ implicit ? implicit : "void context");
+ }
+ if (is_reference || !is_volatile || !is_complete || TREE_ADDRESSABLE (type))
+ {
+ /* Emit a warning (if enabled) when the "effect-less" INDIRECT_REF
+ operation is stripped off. Note that we don't warn about
+ - an expression with TREE_NO_WARNING set. (For an example of
+ such expressions, see build_over_call in call.c.)
+ - automatic dereferencing of references, since the user cannot
+ control it. (See also warn_if_unused_value() in stmt.c.) */
+ if (warn_unused_value
+ && implicit
+ && (complain & tf_warning)
+ && !TREE_NO_WARNING (expr)
+ && !is_reference)
+ warning (OPT_Wunused_value, "value computed is not used");
+ expr = TREE_OPERAND (expr, 0);
+ }
+
+ break;
}
-
+
case VAR_DECL:
{
- /* External variables might be incomplete. */
- tree type = TREE_TYPE (expr);
- int is_complete = COMPLETE_TYPE_P (complete_type (type));
-
- if (TYPE_VOLATILE (type) && !is_complete)
- warning ("object `%E' of incomplete type `%T' will not be accessed in %s",
- expr, type, implicit ? implicit : "void context");
- break;
+ /* External variables might be incomplete. */
+ tree type = TREE_TYPE (expr);
+ int is_complete = COMPLETE_TYPE_P (complete_type (type));
+
+ if (TYPE_VOLATILE (type) && !is_complete && (complain & tf_warning))
+ warning (0, "object %qE of incomplete type %qT will not be accessed in %s",
+ expr, type, implicit ? implicit : "void context");
+ break;
}
+ case TARGET_EXPR:
+ /* Don't bother with the temporary object returned from a function if
+ we don't use it and don't need to destroy it. We'll still
+ allocate space for it in expand_call or declare_return_variable,
+ but we don't need to track it through all the tree phases. */
+ if (TARGET_EXPR_IMPLICIT_P (expr)
+ && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (expr)))
+ {
+ tree init = TARGET_EXPR_INITIAL (expr);
+ if (TREE_CODE (init) == AGGR_INIT_EXPR
+ && !AGGR_INIT_VIA_CTOR_P (init))
+ {
+ tree fn = AGGR_INIT_EXPR_FN (init);
+ expr = build_call_array_loc (input_location,
+ TREE_TYPE (TREE_TYPE (TREE_TYPE (fn))),
+ fn,
+ aggr_init_expr_nargs (init),
+ AGGR_INIT_EXPR_ARGP (init));
+ }
+ }
+ break;
+
default:;
}
+ expr = resolve_nondeduced_context (expr);
{
tree probe = expr;
-
+
if (TREE_CODE (probe) == ADDR_EXPR)
probe = TREE_OPERAND (expr, 0);
if (type_unknown_p (probe))
{
/* [over.over] enumerates the places where we can take the address
of an overloaded function, and this is not one of them. */
- pedwarn ("%s cannot resolve address of overloaded function",
- implicit ? implicit : "void cast");
+ if (complain & tf_error)
+ error ("%s cannot resolve address of overloaded function",
+ implicit ? implicit : "void cast");
+ else
+ return error_mark_node;
expr = void_zero_node;
}
else if (implicit && probe == expr && is_overloaded_fn (probe))
- /* Only warn when there is no &. */
- warning ("%s is a reference, not call, to function `%E'",
- implicit, expr);
+ {
+ /* Only warn when there is no &. */
+ if (complain & tf_warning)
+ warning (OPT_Waddress, "%s is a reference, not call, to function %qE",
+ implicit, expr);
+ if (TREE_CODE (expr) == COMPONENT_REF)
+ expr = TREE_OPERAND (expr, 0);
+ }
}
-
+
if (expr != error_mark_node && !VOID_TYPE_P (TREE_TYPE (expr)))
{
- if (implicit && warn_unused_value
- && !TREE_SIDE_EFFECTS (expr) && !TREE_NO_WARNING (expr))
- warning ("%s has no effect", implicit);
+ if (implicit
+ && warn_unused_value
+ && !TREE_NO_WARNING (expr)
+ && !processing_template_decl)
+ {
+ /* The middle end does not warn about expressions that have
+ been explicitly cast to void, so we must do so here. */
+ if (!TREE_SIDE_EFFECTS (expr)) {
+ if (complain & tf_warning)
+ warning (OPT_Wunused_value, "%s has no effect", implicit);
+ }
+ else
+ {
+ tree e;
+ enum tree_code code;
+ enum tree_code_class tclass;
+
+ e = expr;
+ /* We might like to warn about (say) "(int) f()", as the
+ cast has no effect, but the compiler itself will
+ generate implicit conversions under some
+ circumstances. (For example a block copy will be
+ turned into a call to "__builtin_memcpy", with a
+ conversion of the return value to an appropriate
+ type.) So, to avoid false positives, we strip
+ conversions. Do not use STRIP_NOPs because it will
+ not strip conversions to "void", as that is not a
+ mode-preserving conversion. */
+ while (TREE_CODE (e) == NOP_EXPR)
+ e = TREE_OPERAND (e, 0);
+
+ code = TREE_CODE (e);
+ tclass = TREE_CODE_CLASS (code);
+ if ((tclass == tcc_comparison
+ || tclass == tcc_unary
+ || (tclass == tcc_binary
+ && !(code == MODIFY_EXPR
+ || code == INIT_EXPR
+ || code == PREDECREMENT_EXPR
+ || code == PREINCREMENT_EXPR
+ || code == POSTDECREMENT_EXPR
+ || code == POSTINCREMENT_EXPR)))
+ && (complain & tf_warning))
+ warning (OPT_Wunused_value, "value computed is not used");
+ }
+ }
expr = build1 (CONVERT_EXPR, void_type_node, expr);
}
+ if (! TREE_SIDE_EFFECTS (expr))
+ expr = void_zero_node;
return expr;
}
Most of this routine is from build_reinterpret_cast.
- The backend cannot call cp_convert (what was convert) because
+ The back end cannot call cp_convert (what was convert) because
conversions to/from basetypes may involve memory references
(vbases) and adding or subtracting small values (multiple
inheritance), but it calls convert from the constant folding code
intype = TREE_TYPE (expr);
if (POINTER_TYPE_P (type) && POINTER_TYPE_P (intype))
- {
- expr = decl_constant_value (expr);
- return fold (build1 (NOP_EXPR, type, expr));
- }
+ return fold_if_not_in_template (build_nop (type, expr));
return ocp_convert (type, expr, CONV_OLD_CONVERT,
LOOKUP_NORMAL|LOOKUP_NO_CONVERSION);
enum tree_code code = TREE_CODE (type);
if (code == REFERENCE_TYPE)
- return fold (convert_to_reference (type, e, CONV_C_CAST, LOOKUP_COMPLAIN,
- NULL_TREE));
- else if (TREE_CODE (TREE_TYPE (e)) == REFERENCE_TYPE)
- e = convert_from_reference (e);
+ return (fold_if_not_in_template
+ (convert_to_reference (type, e, CONV_C_CAST, LOOKUP_COMPLAIN,
+ NULL_TREE)));
if (code == POINTER_TYPE)
- return fold (convert_to_pointer_force (type, e));
+ return fold_if_not_in_template (convert_to_pointer_force (type, e));
/* From typeck.c convert_for_assignment */
if (((TREE_CODE (TREE_TYPE (e)) == POINTER_TYPE && TREE_CODE (e) == ADDR_EXPR
|| integer_zerop (e)
|| TYPE_PTRMEMFUNC_P (TREE_TYPE (e)))
&& TYPE_PTRMEMFUNC_P (type))
- {
- /* compatible pointer to member functions. */
- return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), e, 1);
- }
+ /* compatible pointer to member functions. */
+ return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), e, 1,
+ /*c_cast_p=*/1);
return ocp_convert (type, e, CONV_C_CAST|convtype, LOOKUP_NORMAL);
}
that doesn't do it. This will probably wait for an overloading rewrite.
(jason 8/9/95) */
-tree
+static tree
build_type_conversion (tree xtype, tree expr)
{
/* C++: check to see if we can convert this aggregate type
tree conv = NULL_TREE;
tree winner = NULL_TREE;
- if (expr == null_node
- && (desires & WANT_INT)
+ if (expr == null_node
+ && (desires & WANT_INT)
&& !(desires & WANT_NULL))
- warning ("converting NULL to non-pointer type");
-
- expr = convert_from_reference (expr);
+ warning (OPT_Wconversion, "converting NULL to non-pointer type");
+
basetype = TREE_TYPE (expr);
if (basetype == error_mark_node)
return error_mark_node;
- if (! IS_AGGR_TYPE (basetype))
+ if (! MAYBE_CLASS_TYPE_P (basetype))
switch (TREE_CODE (basetype))
{
case INTEGER_TYPE:
return (desires & WANT_FLOAT) ? expr : NULL_TREE;
case POINTER_TYPE:
return (desires & WANT_POINTER) ? expr : NULL_TREE;
-
+
case FUNCTION_TYPE:
case ARRAY_TYPE:
return (desires & WANT_POINTER) ? decay_conversion (expr)
- : NULL_TREE;
+ : NULL_TREE;
+
+ case VECTOR_TYPE:
+ if ((desires & WANT_VECTOR) == 0)
+ return NULL_TREE;
+ switch (TREE_CODE (TREE_TYPE (basetype)))
+ {
+ case INTEGER_TYPE:
+ case BOOLEAN_TYPE:
+ return (desires & WANT_INT) ? expr : NULL_TREE;
+ case ENUMERAL_TYPE:
+ return (desires & WANT_ENUM) ? expr : NULL_TREE;
+ case REAL_TYPE:
+ return (desires & WANT_FLOAT) ? expr : NULL_TREE;
+ default:
+ return NULL_TREE;
+ }
+
default:
return NULL_TREE;
}
if (!TYPE_HAS_CONVERSION (basetype))
return NULL_TREE;
- for (conv = lookup_conversions (basetype); conv; conv = TREE_CHAIN (conv))
+ for (conv = lookup_conversions (basetype, /*lookup_template_convs_p=*/true);
+ conv;
+ conv = TREE_CHAIN (conv))
{
int win = 0;
tree candidate;
tree cand = TREE_VALUE (conv);
+ cand = OVL_CURRENT (cand);
if (winner && winner == cand)
continue;
+ if (DECL_NONCONVERTING_P (cand))
+ continue;
+
candidate = non_reference (TREE_TYPE (TREE_TYPE (cand)));
switch (TREE_CODE (candidate))
case POINTER_TYPE:
win = (desires & WANT_POINTER); break;
+ case VECTOR_TYPE:
+ if ((desires & WANT_VECTOR) == 0)
+ break;
+ switch (TREE_CODE (TREE_TYPE (candidate)))
+ {
+ case BOOLEAN_TYPE:
+ case INTEGER_TYPE:
+ win = (desires & WANT_INT); break;
+ case ENUMERAL_TYPE:
+ win = (desires & WANT_ENUM); break;
+ case REAL_TYPE:
+ win = (desires & WANT_FLOAT); break;
+ default:
+ break;
+ }
+ break;
+
default:
break;
}
{
if (complain)
{
- error ("ambiguous default type conversion from `%T'",
- basetype);
- error (" candidate conversions include `%D' and `%D'",
- winner, cand);
+ error ("ambiguous default type conversion from %qT",
+ basetype);
+ error (" candidate conversions include %qD and %qD",
+ winner, cand);
}
return error_mark_node;
}
tree
type_promotes_to (tree type)
{
+ tree promoted_type;
+
if (type == error_mark_node)
return error_mark_node;
type = TYPE_MAIN_VARIANT (type);
+ /* Check for promotions of target-defined types first. */
+ promoted_type = targetm.promoted_type (type);
+ if (promoted_type)
+ return promoted_type;
+
/* bool always promotes to int (not unsigned), even if it's the same
size. */
- if (type == boolean_type_node)
+ if (TREE_CODE (type) == BOOLEAN_TYPE)
type = integer_type_node;
/* Normally convert enums to int, but convert wide enums to something
wider. */
else if (TREE_CODE (type) == ENUMERAL_TYPE
+ || type == char16_type_node
+ || type == char32_type_node
|| type == wchar_type_node)
{
int precision = MAX (TYPE_PRECISION (type),
}
else if (type == float_type_node)
type = double_type_node;
-
+
return type;
}
to TYPE. Return the resulting expression, or error_mark_node if
the conversion was impossible. */
-tree
+tree
perform_qualification_conversions (tree type, tree expr)
{
tree expr_type;
expr_type = TREE_TYPE (expr);
- if (TYPE_PTR_P (type) && TYPE_PTR_P (expr_type)
- && comp_ptr_ttypes (TREE_TYPE (type), TREE_TYPE (expr_type)))
+ if (same_type_p (type, expr_type))
+ return expr;
+ else if (TYPE_PTR_P (type) && TYPE_PTR_P (expr_type)
+ && comp_ptr_ttypes (TREE_TYPE (type), TREE_TYPE (expr_type)))
return build_nop (type, expr);
else if (TYPE_PTR_TO_MEMBER_P (type)
&& TYPE_PTR_TO_MEMBER_P (expr_type)
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