diff options
Diffstat (limited to 'gnu/usr.bin/cc/cc1plus/cvt.c')
| -rw-r--r-- | gnu/usr.bin/cc/cc1plus/cvt.c | 2041 |
1 files changed, 0 insertions, 2041 deletions
diff --git a/gnu/usr.bin/cc/cc1plus/cvt.c b/gnu/usr.bin/cc/cc1plus/cvt.c deleted file mode 100644 index 444ba27..0000000 --- a/gnu/usr.bin/cc/cc1plus/cvt.c +++ /dev/null @@ -1,2041 +0,0 @@ -/* Language-level data type conversion for GNU C++. - Copyright (C) 1987, 1988, 1992, 1993 Free Software Foundation, Inc. - Hacked by Michael Tiemann (tiemann@cygnus.com) - -This file is part of GNU CC. - -GNU CC 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) -any later version. - -GNU CC is distributed in the hope that it will be useful, -but WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -GNU General Public License for more details. - -You should have received a copy of the GNU General Public License -along with GNU CC; see the file COPYING. If not, write to -the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ - - -/* This file contains the functions for converting C expressions - to different data types. The only entry point is `convert'. - Every language front end must have a `convert' function - but what kind of conversions it does will depend on the language. */ - -#include "config.h" -#include "tree.h" -#include "flags.h" -#include "cp-tree.h" -#include "class.h" -#include "convert.h" - -#undef NULL -#define NULL (char *)0 - -/* Change of width--truncation and extension of integers or reals-- - is represented with NOP_EXPR. Proper functioning of many things - assumes that no other conversions can be NOP_EXPRs. - - Conversion between integer and pointer is represented with CONVERT_EXPR. - Converting integer to real uses FLOAT_EXPR - and real to integer uses FIX_TRUNC_EXPR. - - Here is a list of all the functions that assume that widening and - 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 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. - - C++: in multiple-inheritance, converting between pointers may involve - adjusting them by a delta stored within the class definition. */ - -/* Subroutines of `convert'. */ - -/* Build a thunk. What it is, is an entry point that when called will - adjust the this pointer (the first argument) by offset, and then - goto the real address of the function given by REAL_ADDR that we - would like called. What we return is the address of the thunk. */ -static tree -build_thunk (offset, real_addr) - tree offset, real_addr; -{ - if (TREE_CODE (real_addr) != ADDR_EXPR - || TREE_CODE (TREE_OPERAND (real_addr, 0)) != FUNCTION_DECL) - { - sorry ("MI pointer to member conversion too complex"); - return error_mark_node; - } - sorry ("MI pointer to member conversion too complex"); - return error_mark_node; -} - -/* Convert a `pointer to member' (POINTER_TYPE to METHOD_TYPE) into - another `pointer to method'. This may involved the creation of - a thunk to handle the this offset calculation. */ -static tree -convert_fn_ptr (type, expr) - tree type, expr; -{ - tree binfo = get_binfo (TYPE_METHOD_BASETYPE (TREE_TYPE (TREE_TYPE (expr))), - TYPE_METHOD_BASETYPE (TREE_TYPE (type)), - 1); - if (binfo == error_mark_node) - { - error (" in pointer to member conversion"); - return error_mark_node; - } - if (binfo == NULL_TREE) - { - /* ARM 4.8 restriction. */ - error ("invalid pointer to member conversion"); - return error_mark_node; - } - if (BINFO_OFFSET_ZEROP (binfo)) - return build1 (NOP_EXPR, type, expr); - return build1 (NOP_EXPR, type, build_thunk (BINFO_OFFSET (binfo), expr)); -} - -/* if converting pointer to pointer - if dealing with classes, check for derived->base or vice versa - 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 */ -static tree -cp_convert_to_pointer (type, expr) - tree type, expr; -{ - register tree intype = TREE_TYPE (expr); - register 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 - && TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE) - { - enum tree_code code = PLUS_EXPR; - tree binfo = get_binfo (TREE_TYPE (type), TREE_TYPE (intype), 1); - if (binfo == error_mark_node) - return error_mark_node; - if (binfo == NULL_TREE) - { - binfo = get_binfo (TREE_TYPE (intype), TREE_TYPE (type), 1); - if (binfo == error_mark_node) - return error_mark_node; - code = MINUS_EXPR; - } - if (binfo) - { - if (TYPE_USES_VIRTUAL_BASECLASSES (TREE_TYPE (type)) - || TYPE_USES_VIRTUAL_BASECLASSES (TREE_TYPE (intype)) - || ! BINFO_OFFSET_ZEROP (binfo)) - { - /* Need to get the path we took. */ - tree path; - - if (code == PLUS_EXPR) - get_base_distance (TREE_TYPE (type), TREE_TYPE (intype), 0, &path); - else - get_base_distance (TREE_TYPE (intype), TREE_TYPE (type), 0, &path); - return build_vbase_path (code, type, expr, path, 0); - } - } - } - if (TYPE_MAIN_VARIANT (type) != intype - && TREE_CODE (TREE_TYPE (type)) == METHOD_TYPE - && TREE_CODE (type) == POINTER_TYPE - && TREE_CODE (TREE_TYPE (intype)) == METHOD_TYPE) - return convert_fn_ptr (type, expr); - - return build1 (NOP_EXPR, type, expr); - } - - my_friendly_assert (form != OFFSET_TYPE, 186); - - if (TYPE_LANG_SPECIFIC (intype) - && (IS_SIGNATURE_POINTER (intype) || IS_SIGNATURE_REFERENCE (intype))) - return convert_to_pointer (type, build_optr_ref (expr)); - - if (IS_AGGR_TYPE (intype)) - { - tree rval; - rval = build_type_conversion (CONVERT_EXPR, type, expr, 1); - if (rval) - { - if (rval == error_mark_node) - cp_error ("conversion of `%E' from `%T' to `%T' is ambiguous", - expr, intype, type); - return rval; - } - } - - if (integer_zerop (expr)) - { - if (type == TREE_TYPE (null_pointer_node)) - return null_pointer_node; - expr = build_int_2 (0, 0); - TREE_TYPE (expr) = type; - return expr; - } - - if (INTEGRAL_CODE_P (form)) - { - if (type_precision (intype) == POINTER_SIZE) - return build1 (CONVERT_EXPR, type, expr); - expr = convert (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 (); - return convert_to_pointer (type, expr); - } - - cp_error ("cannot convert `%E' from type `%T' to type `%T'", - expr, intype, type); - return error_mark_node; -} - -/* Like convert, except permit conversions to take place which - are not normally allowed due to access restrictions - (such as conversion from sub-type to private super-type). */ -static tree -convert_to_pointer_force (type, expr) - tree type, expr; -{ - register tree intype = TREE_TYPE (expr); - register enum tree_code form = TREE_CODE (intype); - - if (integer_zerop (expr)) - { - if (type == TREE_TYPE (null_pointer_node)) - return null_pointer_node; - expr = build_int_2 (0, 0); - TREE_TYPE (expr) = type; - return expr; - } - - /* Convert signature pointer/reference to `void *' first. */ - if (form == RECORD_TYPE - && (IS_SIGNATURE_POINTER (intype) || IS_SIGNATURE_REFERENCE (intype))) - { - expr = build_optr_ref (expr); - intype = TREE_TYPE (expr); - 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 - && TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE) - { - enum tree_code code = PLUS_EXPR; - tree path; - int distance = get_base_distance (TREE_TYPE (type), - TREE_TYPE (intype), 0, &path); - if (distance == -2) - { - ambig: - cp_error ("type `%T' is ambiguous baseclass of `%s'", TREE_TYPE (type), - TYPE_NAME_STRING (TREE_TYPE (intype))); - return error_mark_node; - } - if (distance == -1) - { - distance = get_base_distance (TREE_TYPE (intype), - TREE_TYPE (type), 0, &path); - if (distance == -2) - goto ambig; - if (distance < 0) - /* Doesn't need any special help from us. */ - return build1 (NOP_EXPR, type, expr); - - code = MINUS_EXPR; - } - return build_vbase_path (code, type, expr, path, 0); - } - return build1 (NOP_EXPR, type, expr); - } - - return cp_convert_to_pointer (type, expr); -} - -/* We are passing something to a function which requires a reference. - The type we are interested in is in TYPE. The initial - value we have to begin with is in ARG. - - FLAGS controls how we manage access checking. - CHECKCONST controls if we report error messages on const subversion. */ -static tree -build_up_reference (type, arg, flags, checkconst) - tree type, arg; - int flags, checkconst; -{ - tree rval, targ; - int literal_flag = 0; - tree argtype = TREE_TYPE (arg); - tree target_type = TREE_TYPE (type); - tree binfo = NULL_TREE; - - my_friendly_assert (TREE_CODE (type) == REFERENCE_TYPE, 187); - if ((flags & LOOKUP_PROTECT) - && TYPE_MAIN_VARIANT (argtype) != TYPE_MAIN_VARIANT (target_type) - && IS_AGGR_TYPE (argtype) - && IS_AGGR_TYPE (target_type)) - { - binfo = get_binfo (target_type, argtype, 1); - if (binfo == error_mark_node) - return error_mark_node; - if (binfo == NULL_TREE) - return error_not_base_type (target_type, argtype); - } - - /* Pass along const and volatile down into the type. */ - if (TYPE_READONLY (type) || TYPE_VOLATILE (type)) - target_type = cp_build_type_variant (target_type, TYPE_READONLY (type), - TYPE_VOLATILE (type)); - targ = arg; - if (TREE_CODE (targ) == SAVE_EXPR) - targ = TREE_OPERAND (targ, 0); - - switch (TREE_CODE (targ)) - { - case INDIRECT_REF: - /* This is a call to a constructor which did not know what it was - initializing until now: it needs to initialize a temporary. */ - if (TREE_HAS_CONSTRUCTOR (targ)) - { - tree temp = build_cplus_new (argtype, TREE_OPERAND (targ, 0), 1); - TREE_HAS_CONSTRUCTOR (targ) = 0; - return build_up_reference (type, temp, flags, 1); - } - /* Let &* cancel out to simplify resulting code. - Also, throw away intervening NOP_EXPRs. */ - arg = TREE_OPERAND (targ, 0); - if (TREE_CODE (arg) == NOP_EXPR || TREE_CODE (arg) == NON_LVALUE_EXPR - || (TREE_CODE (arg) == CONVERT_EXPR && TREE_REFERENCE_EXPR (arg))) - arg = TREE_OPERAND (arg, 0); - - /* in doing a &*, we have to get rid of the const'ness on the pointer - value. Haven't thought about volatile here. Pointers come to mind - here. */ - if (TREE_READONLY (arg)) - { - arg = copy_node (arg); - TREE_READONLY (arg) = 0; - } - - rval = build1 (CONVERT_EXPR, type, arg); - TREE_REFERENCE_EXPR (rval) = 1; - - /* propagate the const flag on something like: - - class Base { - public: - int foo; - }; - - class Derived : public Base { - public: - int bar; - }; - - void func(Base&); - - void func2(const Derived& d) { - func(d); - } - - on the d parameter. The below could have been avoided, if the flags - were down in the tree, not sure why they are not. (mrs) */ - /* The below code may have to be propagated to other parts of this - switch. */ - if (TREE_READONLY (targ) && !TREE_READONLY (arg) - && (TREE_CODE (arg) == PARM_DECL || TREE_CODE (arg) == VAR_DECL) - && TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE - && (TYPE_READONLY (target_type) && checkconst)) - { - arg = copy_node (arg); - TREE_READONLY (arg) = TREE_READONLY (targ); - } - literal_flag = TREE_CONSTANT (arg); - - goto done; - - /* Get this out of a register if we happened to be in one by accident. - Also, build up references to non-lvalues it we must. */ - /* For &x[y], return (&) x+y */ - case ARRAY_REF: - if (mark_addressable (TREE_OPERAND (targ, 0)) == 0) - return error_mark_node; - rval = build_binary_op (PLUS_EXPR, TREE_OPERAND (targ, 0), - TREE_OPERAND (targ, 1), 1); - TREE_TYPE (rval) = type; - if (TREE_CONSTANT (TREE_OPERAND (targ, 1)) - && staticp (TREE_OPERAND (targ, 0))) - TREE_CONSTANT (rval) = 1; - goto done; - - case SCOPE_REF: - /* Could be a reference to a static member. */ - { - tree field = TREE_OPERAND (targ, 1); - if (TREE_STATIC (field)) - { - rval = build1 (ADDR_EXPR, type, field); - literal_flag = 1; - goto done; - } - } - - /* We should have farmed out member pointers above. */ - my_friendly_abort (188); - - case COMPONENT_REF: - rval = build_component_addr (targ, build_pointer_type (argtype), - "attempt to make a reference to bit-field structure member `%s'"); - TREE_TYPE (rval) = type; - literal_flag = staticp (TREE_OPERAND (targ, 0)); - - goto done; - - /* Anything not already handled and not a true memory reference - needs to have a reference built up. Do so silently for - things like integers and return values from function, - but complain if we need a reference to something declared - as `register'. */ - - case RESULT_DECL: - if (staticp (targ)) - literal_flag = 1; - TREE_ADDRESSABLE (targ) = 1; - put_var_into_stack (targ); - break; - - case PARM_DECL: -#if 0 - if (targ == current_class_decl) - { - error ("address of `this' not available"); -/* #if 0 */ - /* This code makes the following core dump the compiler on a sun4, - if the code below is used. - - class e_decl; - class a_decl; - typedef a_decl* a_ref; - - class a_s { - public: - a_s(); - void* append(a_ref& item); - }; - class a_decl { - public: - a_decl (e_decl *parent); - a_s generic_s; - a_s decls; - e_decl* parent; - }; - - class e_decl { - public: - e_decl(); - a_s implementations; - }; - - void foobar(void *); - - a_decl::a_decl(e_decl *parent) { - parent->implementations.append(this); - } - */ - - TREE_ADDRESSABLE (targ) = 1; /* so compiler doesn't die later */ - put_var_into_stack (targ); - break; -/* #else */ - return error_mark_node; -/* #endif */ - } -#endif - /* Fall through. */ - case VAR_DECL: - case CONST_DECL: - if (DECL_REGISTER (targ) && !TREE_ADDRESSABLE (targ) - && !DECL_ARTIFICIAL (targ)) - cp_warning ("address needed to build reference for `%D', which is declared `register'", - targ); - else if (staticp (targ)) - literal_flag = 1; - - TREE_ADDRESSABLE (targ) = 1; - put_var_into_stack (targ); - break; - - case COMPOUND_EXPR: - { - tree real_reference = build_up_reference (type, TREE_OPERAND (targ, 1), - LOOKUP_PROTECT, checkconst); - rval = build (COMPOUND_EXPR, type, TREE_OPERAND (targ, 0), real_reference); - TREE_CONSTANT (rval) = staticp (TREE_OPERAND (targ, 1)); - return rval; - } - - case PREINCREMENT_EXPR: - case PREDECREMENT_EXPR: - case MODIFY_EXPR: - case INIT_EXPR: - { - tree real_reference = build_up_reference (type, TREE_OPERAND (targ, 0), - LOOKUP_PROTECT, checkconst); - rval = build (COMPOUND_EXPR, type, arg, real_reference); - TREE_CONSTANT (rval) = staticp (TREE_OPERAND (targ, 0)); - return rval; - } - - case COND_EXPR: - return build (COND_EXPR, type, - TREE_OPERAND (targ, 0), - build_up_reference (type, TREE_OPERAND (targ, 1), - LOOKUP_PROTECT, checkconst), - build_up_reference (type, TREE_OPERAND (targ, 2), - LOOKUP_PROTECT, checkconst)); - - case WITH_CLEANUP_EXPR: - return build (WITH_CLEANUP_EXPR, type, - build_up_reference (type, TREE_OPERAND (targ, 0), - LOOKUP_PROTECT, checkconst), - 0, TREE_OPERAND (targ, 2)); - - case BIND_EXPR: - arg = TREE_OPERAND (targ, 1); - if (arg == NULL_TREE) - { - compiler_error ("({ ... }) expression not expanded when needed for reference"); - return error_mark_node; - } - rval = build1 (ADDR_EXPR, type, arg); - TREE_REFERENCE_EXPR (rval) = 1; - return rval; - - default: - break; - } - - if (TREE_ADDRESSABLE (targ) == 0) - { - tree temp; - - if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (argtype)) - { - temp = build_cplus_new (argtype, targ, 1); - if (TREE_CODE (temp) == WITH_CLEANUP_EXPR) - rval = build (WITH_CLEANUP_EXPR, type, - build1 (ADDR_EXPR, type, TREE_OPERAND (temp, 0)), - 0, TREE_OPERAND (temp, 2)); - else - rval = build1 (ADDR_EXPR, type, temp); - goto done; - } - else - { - temp = get_temp_name (argtype, 0); - if (global_bindings_p ()) - { - /* Give this new temp some rtl and initialize it. */ - DECL_INITIAL (temp) = targ; - TREE_STATIC (temp) = 1; - finish_decl (temp, targ, NULL_TREE, 0); - /* Do this after declaring it static. */ - rval = build_unary_op (ADDR_EXPR, temp, 0); - TREE_TYPE (rval) = type; - literal_flag = TREE_CONSTANT (rval); - goto done; - } - else - { - rval = build_unary_op (ADDR_EXPR, temp, 0); - if (binfo && !BINFO_OFFSET_ZEROP (binfo)) - rval = convert_pointer_to (target_type, rval); - else - TREE_TYPE (rval) = type; - - temp = build (MODIFY_EXPR, argtype, temp, arg); - TREE_SIDE_EFFECTS (temp) = 1; - return build (COMPOUND_EXPR, type, temp, rval); - } - } - } - else - rval = build1 (ADDR_EXPR, type, arg); - - done: - if (TYPE_USES_COMPLEX_INHERITANCE (argtype) - || TYPE_USES_COMPLEX_INHERITANCE (target_type)) - { - TREE_TYPE (rval) = build_pointer_type (argtype); - if (flags & LOOKUP_PROTECT) - rval = convert_pointer_to (target_type, rval); - else - rval - = convert_to_pointer_force (build_pointer_type (target_type), rval); - TREE_TYPE (rval) = type; - } - TREE_CONSTANT (rval) = literal_flag; - return rval; -} - -/* For C++: Only need to do one-level references, but cannot - get tripped up on signed/unsigned differences. - - DECL is either NULL_TREE or the _DECL node for a reference that is being - initialized. It can be error_mark_node if we don't know the _DECL but - we know it's an initialization. */ - -tree cp_convert PROTO((tree, tree, int, int)); - -tree -convert_to_reference (reftype, expr, convtype, flags, decl) - tree reftype, expr; - int convtype, flags; - tree decl; -{ - register tree type = TYPE_MAIN_VARIANT (TREE_TYPE (reftype)); - register tree intype = TREE_TYPE (expr); - register enum tree_code form = TREE_CODE (intype); - tree rval = NULL_TREE; - - if (form == REFERENCE_TYPE) - intype = TREE_TYPE (intype); - intype = TYPE_MAIN_VARIANT (intype); - - if (((convtype & CONV_STATIC) && comptypes (type, intype, -1)) - || ((convtype & CONV_IMPLICIT) && comptypes (type, intype, 0))) - { - if (flags & LOOKUP_COMPLAIN) - { - tree ttl = TREE_TYPE (reftype); - tree ttr; - - if (form == REFERENCE_TYPE) - ttr = TREE_TYPE (TREE_TYPE (expr)); - else - { - int r = TREE_READONLY (expr); - int v = TREE_THIS_VOLATILE (expr); - ttr = cp_build_type_variant (TREE_TYPE (expr), r, v); - } - - if (! lvalue_p (expr) && - (decl == NULL_TREE || ! TYPE_READONLY (ttl))) - { - if (decl) - /* Ensure semantics of [dcl.init.ref] */ - cp_pedwarn ("initialization of non-const `%T' from rvalue `%T'", - reftype, intype); - else - cp_pedwarn ("conversion to `%T' from rvalue `%T'", - reftype, intype); - } - else if (! (convtype & CONV_CONST)) - { - if (! TYPE_READONLY (ttl) && TYPE_READONLY (ttr)) - cp_pedwarn ("conversion from `%T' to `%T' discards const", - ttr, reftype); - else if (! TYPE_VOLATILE (ttl) && TYPE_VOLATILE (ttr)) - cp_pedwarn ("conversion from `%T' to `%T' discards volatile", - ttr, reftype); - } - } - - if (form == REFERENCE_TYPE) - { - tree type = TREE_TYPE (expr); - tree tmp = copy_node (expr); - TREE_TYPE (tmp) = build_pointer_type (TREE_TYPE (TREE_TYPE (expr))); - rval = cp_convert (build_pointer_type (TREE_TYPE (reftype)), tmp, - convtype, flags); - TREE_TYPE (tmp) = type; - TREE_TYPE (rval) = reftype; - return rval; - } - - return build_up_reference (reftype, expr, flags, - ! (convtype & CONV_CONST)); - } - - if ((convtype & CONV_IMPLICIT) - && IS_AGGR_TYPE (intype) - && ! (flags & LOOKUP_NO_CONVERSION) - && (rval = build_type_conversion (CONVERT_EXPR, reftype, expr, 1))) - { - if (rval == error_mark_node) - cp_error ("conversion from `%T' to `%T' is ambiguous", - intype, reftype); - return rval; - } - else if ((convtype & CONV_REINTERPRET) && lvalue_p (expr)) - { - /* When casting an lvalue to a reference type, just convert into - a pointer to the new type and deference it. This is allowed - by San Diego WP section 5.2.9 paragraph 12, though perhaps it - should be done directly (jason). (int &)ri ---> *(int*)&ri */ - - /* B* bp; A& ar = (A&)bp; is legal, but it's probably not what they - meant. */ - if (form == POINTER_TYPE - && (comptypes (TREE_TYPE (intype), type, -1))) - cp_warning ("casting `%T' to `%T' does not dereference pointer", - intype, reftype); - - rval = build_unary_op (ADDR_EXPR, expr, 0); - if (rval != error_mark_node) - rval = convert_force (build_pointer_type (TREE_TYPE (reftype)), rval); - if (rval != error_mark_node) - rval = build1 (NOP_EXPR, reftype, rval); - } - else if (decl) - { - tree rval_as_conversion = NULL_TREE; - tree rval_as_ctor = NULL_TREE; - - if (IS_AGGR_TYPE (intype) - && (rval = build_type_conversion (CONVERT_EXPR, type, expr, 1))) - { - if (rval == error_mark_node) - return rval; - - rval_as_conversion = build_up_reference (reftype, rval, flags, 1); - } - - /* Definitely need to go through a constructor here. */ - if (TYPE_HAS_CONSTRUCTOR (type) - && ! CLASSTYPE_ABSTRACT_VIRTUALS (type) - && (rval = build_method_call - (NULL_TREE, constructor_name_full (type), - build_tree_list (NULL_TREE, expr), TYPE_BINFO (type), - LOOKUP_NO_CONVERSION|LOOKUP_SPECULATIVELY))) - { - tree init; - - if (global_bindings_p ()) - { - extern tree static_aggregates; - tree t = get_temp_name (type, global_bindings_p ()); - init = build_method_call (t, constructor_name_full (type), - build_tree_list (NULL_TREE, expr), - TYPE_BINFO (type), - LOOKUP_NORMAL|LOOKUP_NO_CONVERSION); - - if (init == error_mark_node) - return error_mark_node; - - make_decl_rtl (t, NULL_PTR, 1); - static_aggregates = perm_tree_cons (expr, t, static_aggregates); - rval = build_unary_op (ADDR_EXPR, t, 0); - } - else - { - init = build_method_call (NULL_TREE, constructor_name_full (type), - build_tree_list (NULL_TREE, expr), - TYPE_BINFO (type), - LOOKUP_NORMAL|LOOKUP_NO_CONVERSION); - - if (init == error_mark_node) - return error_mark_node; - - rval = build_cplus_new (type, init, 1); - rval = build_up_reference (reftype, rval, flags, 1); - } - rval_as_ctor = rval; - } - - if (rval_as_ctor && rval_as_conversion) - { - cp_error ("ambiguous conversion from `%T' to `%T'; both user-defined conversion and constructor apply", - intype, reftype); - return error_mark_node; - } - else if (rval_as_ctor) - rval = rval_as_ctor; - else if (rval_as_conversion) - rval = rval_as_conversion; - else if (! IS_AGGR_TYPE (type) && ! IS_AGGR_TYPE (intype)) - { - rval = convert (type, expr); - if (rval == error_mark_node) - return error_mark_node; - - rval = build_up_reference (reftype, rval, flags, 1); - } - - if (rval && ! TYPE_READONLY (TREE_TYPE (reftype))) - cp_pedwarn ("initializing non-const `%T' with `%T' will use a temporary", - reftype, intype); - } - - if (rval) - { - /* If we found a way to convert earlier, then use it. */ - return rval; - } - - my_friendly_assert (form != OFFSET_TYPE, 189); - - if (flags & LOOKUP_SPECULATIVELY) - return NULL_TREE; - - else if (flags & LOOKUP_COMPLAIN) - cp_error ("cannot convert type `%T' to type `%T'", intype, reftype); - - return error_mark_node; -} - -/* We are using a reference VAL for its value. Bash that reference all the - way down to its lowest form. */ -tree -convert_from_reference (val) - tree val; -{ - tree type = TREE_TYPE (val); - - if (TREE_CODE (type) == OFFSET_TYPE) - type = TREE_TYPE (type); - if (TREE_CODE (type) == REFERENCE_TYPE) - { - tree target_type = TREE_TYPE (type); - tree nval; - - /* This can happen if we cast to a reference type. */ - if (TREE_CODE (val) == ADDR_EXPR) - { - nval = build1 (NOP_EXPR, build_pointer_type (target_type), val); - nval = build_indirect_ref (nval, NULL_PTR); - /* The below was missing, are other important flags missing too? */ - TREE_SIDE_EFFECTS (nval) = TREE_SIDE_EFFECTS (val); - return nval; - } - - nval = build1 (INDIRECT_REF, target_type, val); - - TREE_THIS_VOLATILE (nval) = TYPE_VOLATILE (target_type); - TREE_SIDE_EFFECTS (nval) = TYPE_VOLATILE (target_type); - TREE_READONLY (nval) = TYPE_READONLY (target_type); - /* The below was missing, are other important flags missing too? */ - TREE_SIDE_EFFECTS (nval) |= TREE_SIDE_EFFECTS (val); - return nval; - } - return val; -} - -/* See if there is a constructor of type TYPE which will convert - EXPR. The reference manual seems to suggest (8.5.6) that we need - not worry about finding constructors for base classes, then converting - to the derived class. - - MSGP is a pointer to a message that would be an appropriate error - string. If MSGP is NULL, then we are not interested in reporting - errors. */ -tree -convert_to_aggr (type, expr, msgp, protect) - tree type, expr; - char **msgp; - int protect; -{ - tree basetype = type; - tree name = TYPE_IDENTIFIER (basetype); - tree function, fndecl, fntype, parmtypes, parmlist, result; - tree method_name; - enum access_type access; - int can_be_private, can_be_protected; - - if (! TYPE_HAS_CONSTRUCTOR (basetype)) - { - if (msgp) - *msgp = "type `%s' does not have a constructor"; - return error_mark_node; - } - - access = access_public; - can_be_private = 0; - can_be_protected = IDENTIFIER_CLASS_VALUE (name) || name == current_class_name; - - parmlist = build_tree_list (NULL_TREE, expr); - parmtypes = tree_cons (NULL_TREE, TREE_TYPE (expr), void_list_node); - - if (TYPE_USES_VIRTUAL_BASECLASSES (basetype)) - { - parmtypes = tree_cons (NULL_TREE, integer_type_node, parmtypes); - parmlist = tree_cons (NULL_TREE, integer_one_node, parmlist); - } - - /* The type of the first argument will be filled in inside the loop. */ - parmlist = tree_cons (NULL_TREE, integer_zero_node, parmlist); - parmtypes = tree_cons (NULL_TREE, TYPE_POINTER_TO (basetype), parmtypes); - - method_name = build_decl_overload (name, parmtypes, 1); - - /* constructors are up front. */ - fndecl = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (basetype), 0); - if (TYPE_HAS_DESTRUCTOR (basetype)) - fndecl = DECL_CHAIN (fndecl); - - while (fndecl) - { - if (DECL_ASSEMBLER_NAME (fndecl) == method_name) - { - function = fndecl; - if (protect) - { - if (TREE_PRIVATE (fndecl)) - { - can_be_private = - (basetype == current_class_type - || is_friend (basetype, current_function_decl) - || purpose_member (basetype, DECL_ACCESS (fndecl))); - if (! can_be_private) - goto found; - } - else if (TREE_PROTECTED (fndecl)) - { - if (! can_be_protected) - goto found; - } - } - goto found_and_ok; - } - fndecl = DECL_CHAIN (fndecl); - } - - /* No exact conversion was found. See if an approximate - one will do. */ - fndecl = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (basetype), 0); - if (TYPE_HAS_DESTRUCTOR (basetype)) - fndecl = DECL_CHAIN (fndecl); - - { - int saw_private = 0; - int saw_protected = 0; - struct candidate *candidates = - (struct candidate *) alloca ((decl_list_length (fndecl)+1) * sizeof (struct candidate)); - struct candidate *cp = candidates; - - while (fndecl) - { - function = fndecl; - cp->h_len = 2; - cp->harshness = (struct harshness_code *) - alloca (3 * sizeof (struct harshness_code)); - - compute_conversion_costs (fndecl, parmlist, cp, 2); - if ((cp->h.code & EVIL_CODE) == 0) - { - cp->u.field = fndecl; - if (protect) - { - if (TREE_PRIVATE (fndecl)) - access = access_private; - else if (TREE_PROTECTED (fndecl)) - access = access_protected; - else - access = access_public; - } - else - access = access_public; - - if (access == access_private - ? (basetype == current_class_type - || is_friend (basetype, cp->function) - || purpose_member (basetype, DECL_ACCESS (fndecl))) - : access == access_protected - ? (can_be_protected - || purpose_member (basetype, DECL_ACCESS (fndecl))) - : 1) - { - if (cp->h.code <= TRIVIAL_CODE) - goto found_and_ok; - cp++; - } - else - { - if (access == access_private) - saw_private = 1; - else - saw_protected = 1; - } - } - fndecl = DECL_CHAIN (fndecl); - } - if (cp - candidates) - { - /* Rank from worst to best. Then cp will point to best one. - Private fields have their bits flipped. For unsigned - numbers, this should make them look very large. - If the best alternate has a (signed) negative value, - then all we ever saw were private members. */ - if (cp - candidates > 1) - qsort (candidates, /* char *base */ - cp - candidates, /* int nel */ - sizeof (struct candidate), /* int width */ - rank_for_overload); /* int (*compar)() */ - - --cp; - if (cp->h.code & EVIL_CODE) - { - if (msgp) - *msgp = "ambiguous type conversion possible for `%s'"; - return error_mark_node; - } - - function = cp->function; - fndecl = cp->u.field; - goto found_and_ok; - } - else if (msgp) - { - if (saw_private) - if (saw_protected) - *msgp = "only private and protected conversions apply"; - else - *msgp = "only private conversions apply"; - else if (saw_protected) - *msgp = "only protected conversions apply"; - else - *msgp = "no appropriate conversion to type `%s'"; - } - return error_mark_node; - } - /* NOTREACHED */ - - found: - if (access == access_private) - if (! can_be_private) - { - if (msgp) - *msgp = TREE_PRIVATE (fndecl) - ? "conversion to type `%s' is private" - : "conversion to type `%s' is from private base class"; - return error_mark_node; - } - if (access == access_protected) - if (! can_be_protected) - { - if (msgp) - *msgp = TREE_PRIVATE (fndecl) - ? "conversion to type `%s' is protected" - : "conversion to type `%s' is from protected base class"; - return error_mark_node; - } - function = fndecl; - found_and_ok: - - /* It will convert, but we don't do anything about it yet. */ - if (msgp == 0) - return NULL_TREE; - - fntype = TREE_TYPE (function); - if (DECL_INLINE (function) && TREE_CODE (function) == FUNCTION_DECL) - function = build1 (ADDR_EXPR, build_pointer_type (fntype), function); - else - function = default_conversion (function); - - result = build_nt (CALL_EXPR, function, - convert_arguments (NULL_TREE, TYPE_ARG_TYPES (fntype), - parmlist, NULL_TREE, LOOKUP_NORMAL), - NULL_TREE); - TREE_TYPE (result) = TREE_TYPE (fntype); - TREE_SIDE_EFFECTS (result) = 1; - TREE_RAISES (result) = !! TYPE_RAISES_EXCEPTIONS (fntype); - return result; -} - -/* Call this when we know (for any reason) that expr is not, in fact, - zero. This routine is like convert_pointer_to, but it pays - attention to which specific instance of what type we want to - convert to. This routine should eventually become - convert_to_pointer after all references to convert_to_pointer - are removed. */ -tree -convert_pointer_to_real (binfo, expr) - tree binfo, expr; -{ - register tree intype = TREE_TYPE (expr); - tree ptr_type; - tree type, rval; - - if (TREE_CODE (binfo) == TREE_VEC) - type = BINFO_TYPE (binfo); - else if (IS_AGGR_TYPE (binfo)) - { - type = binfo; - } - else - { - type = binfo; - binfo = NULL_TREE; - } - - ptr_type = build_pointer_type (type); - if (ptr_type == TYPE_MAIN_VARIANT (intype)) - return expr; - - if (intype == error_mark_node) - return error_mark_node; - - my_friendly_assert (!integer_zerop (expr), 191); - - if (TREE_CODE (type) == RECORD_TYPE - && TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE - && type != TYPE_MAIN_VARIANT (TREE_TYPE (intype))) - { - tree path; - int distance - = get_base_distance (binfo, TYPE_MAIN_VARIANT (TREE_TYPE (intype)), - 0, &path); - - /* This function shouldn't be called with unqualified arguments - but if it is, give them an error message that they can read. */ - if (distance < 0) - { - cp_error ("cannot convert a pointer of type `%T' to a pointer of type `%T'", - TREE_TYPE (intype), type); - - if (distance == -2) - cp_error ("because `%T' is an ambiguous base class", type); - return error_mark_node; - } - - return build_vbase_path (PLUS_EXPR, ptr_type, expr, path, 1); - } - rval = build1 (NOP_EXPR, ptr_type, - TREE_CODE (expr) == NOP_EXPR ? TREE_OPERAND (expr, 0) : expr); - TREE_CONSTANT (rval) = TREE_CONSTANT (expr); - return rval; -} - -/* Call this when we know (for any reason) that expr is - not, in fact, zero. This routine gets a type out of the first - argument and uses it to search for the type to convert to. If there - is more than one instance of that type in the expr, the conversion is - ambiguous. This routine should eventually go away, and all - callers should use convert_to_pointer_real. */ -tree -convert_pointer_to (binfo, expr) - tree binfo, expr; -{ - tree type; - - if (TREE_CODE (binfo) == TREE_VEC) - type = BINFO_TYPE (binfo); - else if (IS_AGGR_TYPE (binfo)) - type = binfo; - else - type = binfo; - return convert_pointer_to_real (type, expr); -} - -/* Same as above, but don't abort if we get an "ambiguous" baseclass. - There's only one virtual baseclass we are looking for, and once - we find one such virtual baseclass, we have found them all. */ - -tree -convert_pointer_to_vbase (binfo, expr) - tree binfo; - tree expr; -{ - tree intype = TREE_TYPE (TREE_TYPE (expr)); - tree binfos = TYPE_BINFO_BASETYPES (intype); - int i; - - for (i = TREE_VEC_LENGTH (binfos)-1; i >= 0; i--) - { - tree basetype = BINFO_TYPE (TREE_VEC_ELT (binfos, i)); - if (BINFO_TYPE (binfo) == basetype) - return convert_pointer_to (binfo, expr); - if (binfo_member (BINFO_TYPE (binfo), CLASSTYPE_VBASECLASSES (basetype))) - return convert_pointer_to_vbase (binfo, convert_pointer_to (basetype, expr)); - } - my_friendly_abort (6); - /* NOTREACHED */ - return NULL_TREE; -} - -tree -cp_convert (type, expr, convtype, flags) - tree type, expr; - int convtype, flags; -{ - register tree e = expr; - register enum tree_code code = TREE_CODE (type); - - if (type == TREE_TYPE (e) - || TREE_CODE (e) == ERROR_MARK) - return e; - if (TREE_CODE (TREE_TYPE (e)) == ERROR_MARK) - return error_mark_node; - - /* Trivial conversion: cv-qualifiers do not matter on rvalues. */ - if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (TREE_TYPE (e))) - return fold (build1 (NOP_EXPR, type, e)); - - if (code == VOID_TYPE && (convtype & CONV_STATIC)) - return build1 (CONVERT_EXPR, type, e); - -#if 0 - /* This is incorrect. A truncation can't be stripped this way. - Extensions will be stripped by the use of get_unwidened. */ - if (TREE_CODE (e) == NOP_EXPR) - return convert (type, TREE_OPERAND (e, 0)); -#endif - - /* Just convert to the type of the member. */ - if (code == OFFSET_TYPE) - { - type = TREE_TYPE (type); - code = TREE_CODE (type); - } - - if (code == REFERENCE_TYPE) - return fold (convert_to_reference (type, e, convtype, flags, NULL_TREE)); - else if (TREE_CODE (TREE_TYPE (e)) == REFERENCE_TYPE) - e = convert_from_reference (e); - - if (TREE_CODE (e) == OFFSET_REF) - e = resolve_offset_ref (e); - - if (TREE_READONLY_DECL_P (e)) - e = decl_constant_value (e); - - if (INTEGRAL_CODE_P (code)) - { - tree intype = TREE_TYPE (e); - enum tree_code form = TREE_CODE (intype); - /* enum = enum, enum = int, enum = float are all errors. */ - if (flag_int_enum_equivalence == 0 - && TREE_CODE (type) == ENUMERAL_TYPE - && ARITHMETIC_TYPE_P (intype)) - { - cp_pedwarn ("conversion from `%#T' to `%#T'", intype, type); - - if (flag_pedantic_errors) - return error_mark_node; - } - if (IS_AGGR_TYPE (intype)) - { - tree rval; - rval = build_type_conversion (CONVERT_EXPR, type, e, 1); - if (rval) - return rval; - cp_error ("`%#T' used where a `%T' was expected", intype, type); - return error_mark_node; - } - if (code == BOOLEAN_TYPE) - { - tree newe = truthvalue_conversion (e); - /* Avoid stupid (infinite) recursion from backend. */ - if (TREE_CODE (newe) != NOP_EXPR || e != TREE_OPERAND (newe, 0)) - e = newe; - if (TREE_TYPE (e) == bool_type_node) - return e; - else if (TREE_CODE (e) == INTEGER_CST) - { - if (e == integer_zero_node) - e = false_node; - else - e = true_node; - } - else - return build1 (NOP_EXPR, bool_type_node, e); - } - return fold (convert_to_integer (type, e)); - } - if (code == POINTER_TYPE) - return fold (cp_convert_to_pointer (type, e)); - if (code == REAL_TYPE) - { - if (IS_AGGR_TYPE (TREE_TYPE (e))) - { - tree rval; - rval = build_type_conversion (CONVERT_EXPR, type, e, 1); - if (rval) - return rval; - else - cp_error ("`%#T' used where a floating point value was expected", - TREE_TYPE (e)); - } - return fold (convert_to_real (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)) - { - tree dtype = TREE_TYPE (e); - tree ctor = NULL_TREE; - tree conversion = NULL_TREE; - - dtype = TYPE_MAIN_VARIANT (dtype); - - /* Conversion of object pointers or signature pointers/references - to signature pointers/references. */ - - if (TYPE_LANG_SPECIFIC (type) - && (IS_SIGNATURE_POINTER (type) || IS_SIGNATURE_REFERENCE (type))) - { - tree constructor = build_signature_pointer_constructor (type, expr); - tree sig_ty = SIGNATURE_TYPE (type); - tree sig_ptr; - - if (constructor == error_mark_node) - return error_mark_node; - - sig_ptr = get_temp_name (type, 1); - DECL_INITIAL (sig_ptr) = constructor; - CLEAR_SIGNATURE (sig_ty); - finish_decl (sig_ptr, constructor, 0, 0); - SET_SIGNATURE (sig_ty); - TREE_READONLY (sig_ptr) = 1; - - return sig_ptr; - } - - /* Conversion between aggregate types. New C++ semantics allow - objects of derived type to be cast to objects of base type. - Old semantics only allowed this between pointers. - - There may be some ambiguity between using a constructor - vs. using a type conversion operator when both apply. */ - - if (IS_AGGR_TYPE (dtype) && ! DERIVED_FROM_P (type, dtype) - && TYPE_HAS_CONVERSION (dtype)) - conversion = build_type_conversion (CONVERT_EXPR, type, e, 1); - - if (conversion == error_mark_node) - { - error ("ambiguous pointer conversion"); - return conversion; - } - - if (TYPE_HAS_CONSTRUCTOR (type)) - ctor = build_method_call (NULL_TREE, constructor_name_full (type), - build_tree_list (NULL_TREE, e), - TYPE_BINFO (type), - LOOKUP_NORMAL | LOOKUP_SPECULATIVELY - | (conversion ? LOOKUP_NO_CONVERSION : 0)); - - if (ctor == error_mark_node) - { - cp_error ("in conversion to type `%T'", type); - return error_mark_node; - } - - if (conversion && ctor) - { - error ("both constructor and type conversion operator apply"); - return error_mark_node; - } - else if (conversion) - return conversion; - else if (ctor) - { - if (current_function_decl) - /* We can't pass 1 to the with_cleanup_p arg here, because that - screws up passing classes by value. */ - ctor = build_cplus_new (type, ctor, 0); - else - { - register tree parm = TREE_OPERAND (ctor, 1); - - /* Initializers for static variables and parameters - have to handle doing the initialization and - cleanup themselves. */ - my_friendly_assert (TREE_CODE (ctor) == CALL_EXPR, 322); -#if 0 - /* The following assertion fails in cases where we - are initializing a static member variable of a - particular instance of a template class with a - call to a constructor of the given instance, as - in: - - TMPL<int> object = TMPL<int>(); - - Curiously, the assertion does not fail if we do - the same thing for a static member of a - non-template class, as in: - - T object = T(); - - I can't see why we should care here whether or not - the initializer expression involves a call to - `new', so for the time being, it seems best to - just avoid doing this assertion. */ - my_friendly_assert (TREE_CALLS_NEW (TREE_VALUE (parm)), - 323); -#endif - TREE_VALUE (parm) = NULL_TREE; - ctor = build_indirect_ref (ctor, NULL_PTR); - TREE_HAS_CONSTRUCTOR (ctor) = 1; - } - return ctor; - } - } - - /* If TYPE or TREE_TYPE (E) is not on the permanent_obstack, - then the it won't be hashed and hence compare as not equal, - even when it is. */ - if (code == ARRAY_TYPE - && TREE_TYPE (TREE_TYPE (e)) == TREE_TYPE (type) - && index_type_equal (TYPE_DOMAIN (TREE_TYPE (e)), TYPE_DOMAIN (type))) - return e; - - cp_error ("conversion from `%T' to non-scalar type `%T' requested", - TREE_TYPE (expr), type); - return error_mark_node; -} - -/* Create an expression whose value is that of EXPR, - converted to type TYPE. The TREE_TYPE of the value - is always TYPE. This function implements all reasonable - conversions; callers should filter out those that are - not permitted by the language being compiled. */ - -tree -convert (type, expr) - tree type, expr; -{ - return cp_convert (type, expr, CONV_OLD_CONVERT, 0); -} - -/* Like convert, except permit conversions to take place which - are not normally allowed due to access restrictions - (such as conversion from sub-type to private super-type). */ -tree -convert_force (type, expr) - tree type; - tree expr; -{ - register tree e = expr; - register 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); - - if (code == POINTER_TYPE) - return fold (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 - && TREE_CODE (TREE_TYPE (e)) == POINTER_TYPE - && TREE_CODE (TREE_TYPE (TREE_TYPE (e))) == METHOD_TYPE) - || 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); - } - { - int old_equiv = flag_int_enum_equivalence; - flag_int_enum_equivalence = 1; - e = convert (type, e); - flag_int_enum_equivalence = old_equiv; - } - return e; -} - -/* Subroutine of build_type_conversion. */ -static tree -build_type_conversion_1 (xtype, basetype, expr, typename, for_sure) - tree xtype, basetype; - tree expr; - tree typename; - int for_sure; -{ - tree rval; - int flags; - - if (for_sure == 0) - flags = LOOKUP_PROTECT; - else - flags = LOOKUP_NORMAL; - - rval = build_method_call (expr, typename, NULL_TREE, NULL_TREE, flags); - if (rval == error_mark_node) - { - if (for_sure == 0) - return NULL_TREE; - return error_mark_node; - } - if (TREE_CODE (TREE_TYPE (rval)) == REFERENCE_TYPE - && TREE_CODE (xtype) != REFERENCE_TYPE) - rval = default_conversion (rval); - - if (warn_cast_qual - && TREE_TYPE (xtype) - && (TREE_READONLY (TREE_TYPE (TREE_TYPE (rval))) - > TREE_READONLY (TREE_TYPE (xtype)))) - warning ("user-defined conversion casting away `const'"); - return convert (xtype, rval); -} - -/* Convert an aggregate EXPR to type XTYPE. If a conversion - exists, return the attempted conversion. This may - return ERROR_MARK_NODE if the conversion is not - allowed (references private members, etc). - If no conversion exists, NULL_TREE is returned. - - If (FOR_SURE & 1) is non-zero, then we allow this type conversion - to take place immediately. Otherwise, we build a SAVE_EXPR - which can be evaluated if the results are ever needed. - - If FOR_SURE >= 2, then we only look for exact conversions. - - TYPE may be a reference type, in which case we first look - for something that will convert to a reference type. If - that fails, we will try to look for something of the - reference's target type, and then return a reference to that. */ -tree -build_type_conversion (code, xtype, expr, for_sure) - enum tree_code code; - tree xtype, expr; - int for_sure; -{ - /* C++: check to see if we can convert this aggregate type - into the required scalar type. */ - tree type, type_default; - tree typename = build_typename_overload (xtype), *typenames; - int n_variants = 0; - tree basetype, save_basetype; - tree rval; - int exact_conversion = for_sure >= 2; - for_sure &= 1; - - if (expr == error_mark_node) - return error_mark_node; - - basetype = TREE_TYPE (expr); - if (TREE_CODE (basetype) == REFERENCE_TYPE) - basetype = TREE_TYPE (basetype); - - if (TYPE_PTRMEMFUNC_P (basetype) && TREE_CODE (xtype) == BOOLEAN_TYPE) - { - /* We convert a pointer to member function into a boolean, - by just checking the index value, for == 0, we want false, for - != 0, we want true. */ - return convert (xtype, build_component_ref (expr, index_identifier, 0, 0)); - } - - basetype = TYPE_MAIN_VARIANT (basetype); - if (! TYPE_LANG_SPECIFIC (basetype) || ! TYPE_HAS_CONVERSION (basetype)) - return NULL_TREE; - - if (TREE_CODE (xtype) == POINTER_TYPE - || TREE_CODE (xtype) == REFERENCE_TYPE) - { - /* Prepare to match a variant of this type. */ - type = TYPE_MAIN_VARIANT (TREE_TYPE (xtype)); - for (n_variants = 0; type; type = TYPE_NEXT_VARIANT (type)) - n_variants++; - typenames = (tree *)alloca (n_variants * sizeof (tree)); - for (n_variants = 0, type = TYPE_MAIN_VARIANT (TREE_TYPE (xtype)); - type; n_variants++, type = TYPE_NEXT_VARIANT (type)) - { - if (type == TREE_TYPE (xtype)) - typenames[n_variants] = typename; - else if (TREE_CODE (xtype) == POINTER_TYPE) - typenames[n_variants] = build_typename_overload (build_pointer_type (type)); - else - typenames[n_variants] = build_typename_overload (build_reference_type (type)); - } - } - - save_basetype = basetype; - type = xtype; - - while (TYPE_HAS_CONVERSION (basetype)) - { - int i; - if (lookup_fnfields (TYPE_BINFO (basetype), typename, 0)) - return build_type_conversion_1 (xtype, basetype, expr, typename, for_sure); - for (i = 0; i < n_variants; i++) - if (typenames[i] != typename - && lookup_fnfields (TYPE_BINFO (basetype), typenames[i], 0)) - return build_type_conversion_1 (xtype, basetype, expr, typenames[i], for_sure); - - if (TYPE_BINFO_BASETYPES (basetype)) - basetype = TYPE_BINFO_BASETYPE (basetype, 0); - else - break; - } - - if (TREE_CODE (type) == REFERENCE_TYPE) - { -#if 0 - /* Only reference variable initializations can use a temporary; this - must be handled elsewhere (like convert_to_reference and - compute_conversion_costs). */ - - type = TYPE_MAIN_VARIANT (TREE_TYPE (type)); - typename = build_typename_overload (type); - basetype = save_basetype; - - /* May need to build a temporary for this. */ - while (TYPE_HAS_CONVERSION (basetype)) - { - if (lookup_fnfields (TYPE_BINFO (basetype), typename, 0)) - { - int flags; - - if (for_sure == 0) - flags = LOOKUP_PROTECT; - else - flags = LOOKUP_NORMAL; - rval = build_method_call (expr, - constructor_name_full (typename), - NULL_TREE, NULL_TREE, flags); - if (rval == error_mark_node) - { - if (for_sure == 0) - return NULL_TREE; - return error_mark_node; - } - - return convert (xtype, rval); - } - if (TYPE_BINFO_BASETYPES (basetype)) - basetype = TYPE_BINFO_BASETYPE (basetype, 0); - else - break; - } -#endif - /* No free conversions for reference types, right?. */ - return NULL_TREE; - } - - if (exact_conversion) - return NULL_TREE; - - if (TREE_CODE (type) == BOOLEAN_TYPE) - { - tree as_int = build_type_conversion (code, long_long_unsigned_type_node, expr, 0); - tree as_ptr = build_type_conversion (code, ptr_type_node, expr, 0); - /* We are missing the conversion to pointer to member type. */ - /* We are missing the conversion to floating type. */ - if (as_int && as_ptr && for_sure) - { - cp_error ("ambiguous conversion from `%T' to `bool', can convert to integral type or pointer", TREE_TYPE (expr)); - return error_mark_node; - } - if (as_int) - { - as_int = build_type_conversion (code, long_long_unsigned_type_node, expr, for_sure+exact_conversion*2); - return convert (xtype, as_int); - } - if (as_ptr) - { - as_ptr = build_type_conversion (code, ptr_type_node, expr, for_sure+exact_conversion*2); - return convert (xtype, as_ptr); - } - return NULL_TREE; - } - - /* No perfect match found, try default. */ -#if 0 /* This is wrong; there is no standard conversion from void* to - anything. -jason */ - if (code == CONVERT_EXPR && TREE_CODE (type) == POINTER_TYPE) - type_default = ptr_type_node; - else -#endif - if (type == void_type_node) - return NULL_TREE; - else - { - tree tmp = default_conversion (build1 (NOP_EXPR, type, integer_zero_node)); - if (tmp == error_mark_node) - return NULL_TREE; - type_default = TREE_TYPE (tmp); - } - - basetype = save_basetype; - - if (type_default != type) - { - type = type_default; - typename = build_typename_overload (type); - - while (TYPE_HAS_CONVERSION (basetype)) - { - if (lookup_fnfields (TYPE_BINFO (basetype), typename, 0)) - return build_type_conversion_1 (xtype, basetype, expr, typename, for_sure); - if (TYPE_BINFO_BASETYPES (basetype)) - basetype = TYPE_BINFO_BASETYPE (basetype, 0); - else - break; - } - } - - if (TREE_CODE (type) == POINTER_TYPE && TYPE_READONLY (TREE_TYPE (type))) - { - /* Try converting to some other const pointer type and then using - standard conversions. */ - - while (TYPE_HAS_CONVERSION (basetype)) - { - if (CLASSTYPE_CONVERSION (basetype, constptr_conv) != 0) - { - if (CLASSTYPE_CONVERSION (basetype, constptr_conv) == error_mark_node) - return error_mark_node; - typename = DECL_NAME (CLASSTYPE_CONVERSION (basetype, constptr_conv)); - return build_type_conversion_1 (xtype, basetype, expr, typename, for_sure); - } - if (TYPE_BINFO_BASETYPES (basetype)) - basetype = TYPE_BINFO_BASETYPE (basetype, 0); - else - break; - } - } - if (TREE_CODE (type) == POINTER_TYPE) - { - /* Try converting to some other pointer type and then using standard - conversions. */ - - while (TYPE_HAS_CONVERSION (basetype)) - { - if (CLASSTYPE_CONVERSION (basetype, ptr_conv) != 0) - { - if (CLASSTYPE_CONVERSION (basetype, ptr_conv) == error_mark_node) - return error_mark_node; - typename = DECL_NAME (CLASSTYPE_CONVERSION (basetype, ptr_conv)); - return build_type_conversion_1 (xtype, basetype, expr, typename, for_sure); - } - if (TYPE_BINFO_BASETYPES (basetype)) - basetype = TYPE_BINFO_BASETYPE (basetype, 0); - else - break; - } - } - - /* Use the longer or shorter conversion that is appropriate. Have - to check against 0 because the conversion may come from a baseclass. */ - if (TREE_CODE (type) == INTEGER_TYPE - && TYPE_HAS_INT_CONVERSION (basetype) - && CLASSTYPE_CONVERSION (basetype, int_conv) != 0 - && CLASSTYPE_CONVERSION (basetype, int_conv) != error_mark_node) - { - typename = DECL_NAME (CLASSTYPE_CONVERSION (basetype, int_conv)); - return build_type_conversion_1 (xtype, basetype, expr, typename, for_sure); - } - - if (TREE_CODE (type) == REAL_TYPE - && TYPE_HAS_REAL_CONVERSION (basetype) - && CLASSTYPE_CONVERSION (basetype, real_conv) != 0 - && CLASSTYPE_CONVERSION (basetype, real_conv) != error_mark_node) - { - /* Only accept using an operator double() if there isn't a conflicting - operator int(). */ - if (TYPE_HAS_INT_CONVERSION (basetype)) - { - if (for_sure) - { - cp_error ("two possible conversions for type `%T'", type); - return error_mark_node; - } - else - return NULL_TREE; - } - - typename = DECL_NAME (CLASSTYPE_CONVERSION (basetype, real_conv)); - return build_type_conversion_1 (xtype, basetype, expr, typename, for_sure); - } - - /* THESE ARE TOTAL KLUDGES. */ - /* Default promotion yields no new alternatives, try - conversions which are anti-default, such as - - double -> float or int -> unsigned or unsigned -> long - - */ - if (type_default == type - && (INTEGRAL_TYPE_P (type) || TREE_CODE (type) == REAL_TYPE)) - { - int not_again = 0; - - if (type == double_type_node) - typename = build_typename_overload (float_type_node); - else if (type == integer_type_node) - typename = build_typename_overload (unsigned_type_node); - else if (type == unsigned_type_node) - typename = build_typename_overload (long_integer_type_node); - - again: - basetype = save_basetype; - while (TYPE_HAS_CONVERSION (basetype)) - { - if (lookup_fnfields (TYPE_BINFO (basetype), typename, 0)) - return build_type_conversion_1 (xtype, basetype, expr, typename, for_sure); - if (TYPE_BINFO_BASETYPES (basetype)) - basetype = TYPE_BINFO_BASETYPE (basetype, 0); - else - break; - } - if (! not_again) - { - if (type == integer_type_node) - { - typename = build_typename_overload (long_integer_type_node); - not_again = 1; - goto again; - } - else - { - typename = build_typename_overload (integer_type_node); - not_again = 1; - goto again; - } - } - } - - /* Now, try C promotions... - - float -> int - int -> float */ - - basetype = save_basetype; - if (TREE_CODE (type) == REAL_TYPE) - type = integer_type_node; - else if (TREE_CODE (type) == INTEGER_TYPE) - if (TYPE_HAS_REAL_CONVERSION (basetype)) - type = double_type_node; - else - return NULL_TREE; - else - return NULL_TREE; - - typename = build_typename_overload (type); - while (TYPE_HAS_CONVERSION (basetype)) - { - if (lookup_fnfields (TYPE_BINFO (basetype), typename, 0)) - { - rval = build_type_conversion_1 (xtype, basetype, expr, typename, for_sure); - return rval; - } - if (TYPE_BINFO_BASETYPES (basetype)) - basetype = TYPE_BINFO_BASETYPE (basetype, 0); - else - break; - } - - return NULL_TREE; -} - -/* Must convert two aggregate types to non-aggregate type. - Attempts to find a non-ambiguous, "best" type conversion. - - Return 1 on success, 0 on failure. - - @@ What are the real semantics of this supposed to be??? */ -int -build_default_binary_type_conversion (code, arg1, arg2) - enum tree_code code; - tree *arg1, *arg2; -{ - tree type1 = TREE_TYPE (*arg1); - tree type2 = TREE_TYPE (*arg2); - - if (TREE_CODE (type1) == REFERENCE_TYPE - || TREE_CODE (type1) == POINTER_TYPE) - type1 = TREE_TYPE (type1); - if (TREE_CODE (type2) == REFERENCE_TYPE - || TREE_CODE (type2) == POINTER_TYPE) - type2 = TREE_TYPE (type2); - - if (TREE_CODE (TYPE_NAME (type1)) != TYPE_DECL) - { - tree decl = typedecl_for_tag (type1); - if (decl) - error ("type conversion nonexistent for type `%s'", - IDENTIFIER_POINTER (DECL_NAME (decl))); - else - error ("type conversion nonexistent for non-C++ type"); - return 0; - } - if (TREE_CODE (TYPE_NAME (type2)) != TYPE_DECL) - { - tree decl = typedecl_for_tag (type2); - if (decl) - error ("type conversion nonexistent for type `%s'", - IDENTIFIER_POINTER (decl)); - else - error ("type conversion nonexistent for non-C++ type"); - return 0; - } - - if (!IS_AGGR_TYPE (type1) || !TYPE_HAS_CONVERSION (type1)) - { - if (!IS_AGGR_TYPE (type2) || !TYPE_HAS_CONVERSION (type2)) - cp_error ("no conversion from `%T' and `%T' to types with default `%O' ", - type1, type2, code); - else - cp_error ("no conversion from `%T' to type with default `%O'", - type1, code); - return 0; - } - else if (!IS_AGGR_TYPE (type2) || !TYPE_HAS_CONVERSION (type2)) - { - cp_error ("no conversion from `%T' to type with default `%O'", - type2, code); - return 0; - } - - if (code == TRUTH_ANDIF_EXPR - || code == TRUTH_ORIF_EXPR) - { - *arg1 = convert (bool_type_node, *arg1); - *arg2 = convert (bool_type_node, *arg2); - } - else if (TYPE_HAS_INT_CONVERSION (type1)) - { - if (TYPE_HAS_REAL_CONVERSION (type1)) - cp_pedwarn ("ambiguous type conversion for type `%T', defaulting to int", - type1); - *arg1 = build_type_conversion (code, integer_type_node, *arg1, 1); - *arg2 = build_type_conversion (code, integer_type_node, *arg2, 1); - } - else if (TYPE_HAS_REAL_CONVERSION (type1)) - { - *arg1 = build_type_conversion (code, double_type_node, *arg1, 1); - *arg2 = build_type_conversion (code, double_type_node, *arg2, 1); - } - else - { - *arg1 = build_type_conversion (code, ptr_type_node, *arg1, 1); - if (*arg1 == error_mark_node) - error ("ambiguous pointer conversion"); - *arg2 = build_type_conversion (code, ptr_type_node, *arg2, 1); - if (*arg1 != error_mark_node && *arg2 == error_mark_node) - error ("ambiguous pointer conversion"); - } - if (*arg1 == 0) - { - if (*arg2 == 0 && type1 != type2) - cp_error ("default type conversion for types `%T' and `%T' failed", - type1, type2); - else - cp_error ("default type conversion for type `%T' failed", type1); - return 0; - } - else if (*arg2 == 0) - { - cp_error ("default type conversion for type `%T' failed", type2); - return 0; - } - return 1; -} - -/* Must convert an aggregate type to non-aggregate type. - Attempts to find a non-ambiguous, "best" type conversion. - - Return 1 on success, 0 on failure. - - The type of the argument is expected to be of aggregate type here. - - @@ What are the real semantics of this supposed to be??? */ -int -build_default_unary_type_conversion (code, arg) - enum tree_code code; - tree *arg; -{ - tree type = TREE_TYPE (*arg); - - if (! TYPE_HAS_CONVERSION (type)) - { - cp_error ("type conversion required for type `%T'", type); - return 0; - } - - if (code == TRUTH_NOT_EXPR) - *arg = convert (bool_type_node, *arg); - else if (TYPE_HAS_INT_CONVERSION (type)) - { - if (TYPE_HAS_REAL_CONVERSION (type)) - cp_pedwarn ("ambiguous type conversion for type `%T', defaulting to int", - type); - *arg = build_type_conversion (code, integer_type_node, *arg, 1); - } - else if (TYPE_HAS_REAL_CONVERSION (type)) - *arg = build_type_conversion (code, double_type_node, *arg, 1); - else - { - *arg = build_type_conversion (code, ptr_type_node, *arg, 1); - if (*arg == error_mark_node) - error ("ambiguous pointer conversion"); - } - if (*arg == NULL_TREE) - { - cp_error ("default type conversion for type `%T' failed", type); - return 0; - } - return 1; -} - -/* Implements integral promotion (4.1) and float->double promotion. */ -tree -type_promotes_to (type) - tree type; -{ - int constp = TYPE_READONLY (type); - int volatilep = TYPE_VOLATILE (type); - type = TYPE_MAIN_VARIANT (type); - - /* bool always promotes to int (not unsigned), even if it's the same - size. */ - if (type == bool_type_node) - type = integer_type_node; - - /* Normally convert enums to int, but convert wide enums to something - wider. */ - else if (TREE_CODE (type) == ENUMERAL_TYPE - || type == wchar_type_node) - { - int precision = MAX (TYPE_PRECISION (type), - TYPE_PRECISION (integer_type_node)); - tree totype = type_for_size (precision, 0); - if (TREE_UNSIGNED (type) - && ! int_fits_type_p (TYPE_MAX_VALUE (type), totype)) - type = type_for_size (precision, 1); - else - type = totype; - } - else if (C_PROMOTING_INTEGER_TYPE_P (type)) - { - /* Traditionally, unsignedness is preserved in default promotions. - Otherwise, retain unsignedness if really not getting bigger. */ - if (TREE_UNSIGNED (type) - && (flag_traditional - || TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))) - type = unsigned_type_node; - else - type = integer_type_node; - } - else if (type == float_type_node) - type = double_type_node; - - return cp_build_type_variant (type, constp, volatilep); -} |
