]>
Commit | Line | Data |
---|---|---|
8d08fdba | 1 | /* Language-level data type conversion for GNU C++. |
5624e564 | 2 | Copyright (C) 1987-2015 Free Software Foundation, Inc. |
8d08fdba MS |
3 | Hacked by Michael Tiemann (tiemann@cygnus.com) |
4 | ||
f5adbb8d | 5 | This file is part of GCC. |
8d08fdba | 6 | |
f5adbb8d | 7 | GCC is free software; you can redistribute it and/or modify |
8d08fdba | 8 | it under the terms of the GNU General Public License as published by |
e77f031d | 9 | the Free Software Foundation; either version 3, or (at your option) |
8d08fdba MS |
10 | any later version. |
11 | ||
f5adbb8d | 12 | GCC is distributed in the hope that it will be useful, |
8d08fdba MS |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
e77f031d NC |
18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ | |
8d08fdba MS |
20 | |
21 | ||
3fd5abcf | 22 | /* This file contains the functions for converting C++ expressions |
8d08fdba MS |
23 | to different data types. The only entry point is `convert'. |
24 | Every language front end must have a `convert' function | |
25 | but what kind of conversions it does will depend on the language. */ | |
26 | ||
27 | #include "config.h" | |
8d052bc7 | 28 | #include "system.h" |
4977bab6 ZW |
29 | #include "coretypes.h" |
30 | #include "tm.h" | |
40e23961 | 31 | #include "alias.h" |
8d08fdba | 32 | #include "tree.h" |
d8a2d370 | 33 | #include "stor-layout.h" |
8d08fdba MS |
34 | #include "flags.h" |
35 | #include "cp-tree.h" | |
f25a2b52 | 36 | #include "intl.h" |
8d08fdba | 37 | #include "convert.h" |
ddaed37e | 38 | #include "decl.h" |
4de67c26 | 39 | #include "target.h" |
e92cc029 | 40 | |
4b978f96 PC |
41 | static tree cp_convert_to_pointer (tree, tree, tsubst_flags_t); |
42 | static tree convert_to_pointer_force (tree, tree, tsubst_flags_t); | |
ae00383b | 43 | static tree build_type_conversion (tree, tree); |
4b978f96 | 44 | static tree build_up_reference (tree, tree, int, tree, tsubst_flags_t); |
76545796 | 45 | static void diagnose_ref_binding (location_t, tree, tree, tree); |
49c249e1 | 46 | |
8d08fdba MS |
47 | /* Change of width--truncation and extension of integers or reals-- |
48 | is represented with NOP_EXPR. Proper functioning of many things | |
49 | assumes that no other conversions can be NOP_EXPRs. | |
50 | ||
51 | Conversion between integer and pointer is represented with CONVERT_EXPR. | |
52 | Converting integer to real uses FLOAT_EXPR | |
53 | and real to integer uses FIX_TRUNC_EXPR. | |
54 | ||
55 | Here is a list of all the functions that assume that widening and | |
56 | narrowing is always done with a NOP_EXPR: | |
57 | In convert.c, convert_to_integer. | |
58 | In c-typeck.c, build_binary_op_nodefault (boolean ops), | |
0cbd7506 | 59 | and c_common_truthvalue_conversion. |
8d08fdba MS |
60 | In expr.c: expand_expr, for operands of a MULT_EXPR. |
61 | In fold-const.c: fold. | |
62 | In tree.c: get_narrower and get_unwidened. | |
63 | ||
64 | C++: in multiple-inheritance, converting between pointers may involve | |
65 | adjusting them by a delta stored within the class definition. */ | |
66 | \f | |
67 | /* Subroutines of `convert'. */ | |
68 | ||
8d08fdba MS |
69 | /* if converting pointer to pointer |
70 | if dealing with classes, check for derived->base or vice versa | |
71 | else if dealing with method pointers, delegate | |
72 | else convert blindly | |
73 | else if converting class, pass off to build_type_conversion | |
6e03b280 | 74 | else try C-style pointer conversion. */ |
e92cc029 | 75 | |
8d08fdba | 76 | static tree |
4b978f96 | 77 | cp_convert_to_pointer (tree type, tree expr, tsubst_flags_t complain) |
8d08fdba | 78 | { |
926ce8bd KH |
79 | tree intype = TREE_TYPE (expr); |
80 | enum tree_code form; | |
31bcaa20 | 81 | tree rval; |
8400e75e | 82 | location_t loc = EXPR_LOC_OR_LOC (expr, input_location); |
5a3c9cf2 | 83 | |
0c482362 AP |
84 | if (intype == error_mark_node) |
85 | return error_mark_node; | |
71851aaa | 86 | |
9e1e64ec | 87 | if (MAYBE_CLASS_TYPE_P (intype)) |
e92cc029 | 88 | { |
e92cc029 | 89 | intype = complete_type (intype); |
d0f062fb | 90 | if (!COMPLETE_TYPE_P (intype)) |
e92cc029 | 91 | { |
4b978f96 PC |
92 | if (complain & tf_error) |
93 | error_at (loc, "can%'t convert from incomplete type %qT to %qT", | |
94 | intype, type); | |
e92cc029 MS |
95 | return error_mark_node; |
96 | } | |
97 | ||
7993382e | 98 | rval = build_type_conversion (type, expr); |
e92cc029 MS |
99 | if (rval) |
100 | { | |
4b978f96 PC |
101 | if ((complain & tf_error) |
102 | && rval == error_mark_node) | |
5a3c9cf2 PC |
103 | error_at (loc, "conversion of %qE from %qT to %qT is ambiguous", |
104 | expr, intype, type); | |
e92cc029 MS |
105 | return rval; |
106 | } | |
107 | } | |
108 | ||
faf5394a | 109 | /* Handle anachronistic conversions from (::*)() to cv void* or (*)(). */ |
50e10fa8 | 110 | if (TYPE_PTR_P (type) |
9a3b49ac | 111 | && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE |
b72801e2 | 112 | || VOID_TYPE_P (TREE_TYPE (type)))) |
9a3b49ac | 113 | { |
33c25e5c MM |
114 | if (TYPE_PTRMEMFUNC_P (intype) |
115 | || TREE_CODE (intype) == METHOD_TYPE) | |
4b978f96 | 116 | return convert_member_func_to_ptr (type, expr, complain); |
50e10fa8 | 117 | if (TYPE_PTR_P (TREE_TYPE (expr))) |
d6b4ea85 | 118 | return build_nop (type, expr); |
9a3b49ac MS |
119 | intype = TREE_TYPE (expr); |
120 | } | |
121 | ||
c87978aa JM |
122 | if (expr == error_mark_node) |
123 | return error_mark_node; | |
124 | ||
71851aaa MS |
125 | form = TREE_CODE (intype); |
126 | ||
d8f8dca1 | 127 | if (POINTER_TYPE_P (intype)) |
8d08fdba MS |
128 | { |
129 | intype = TYPE_MAIN_VARIANT (intype); | |
130 | ||
131 | if (TYPE_MAIN_VARIANT (type) != intype | |
50e10fa8 | 132 | && TYPE_PTR_P (type) |
8d08fdba | 133 | && TREE_CODE (TREE_TYPE (type)) == RECORD_TYPE |
9e1e64ec PC |
134 | && MAYBE_CLASS_TYPE_P (TREE_TYPE (type)) |
135 | && MAYBE_CLASS_TYPE_P (TREE_TYPE (intype)) | |
338d90b8 | 136 | && TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE) |
8d08fdba MS |
137 | { |
138 | enum tree_code code = PLUS_EXPR; | |
338d90b8 | 139 | tree binfo; |
7993382e MM |
140 | tree intype_class; |
141 | tree type_class; | |
142 | bool same_p; | |
338d90b8 | 143 | |
7993382e MM |
144 | intype_class = TREE_TYPE (intype); |
145 | type_class = TREE_TYPE (type); | |
146 | ||
c8094d83 | 147 | same_p = same_type_p (TYPE_MAIN_VARIANT (intype_class), |
7993382e MM |
148 | TYPE_MAIN_VARIANT (type_class)); |
149 | binfo = NULL_TREE; | |
00a17e31 | 150 | /* Try derived to base conversion. */ |
7993382e | 151 | if (!same_p) |
22854930 PC |
152 | binfo = lookup_base (intype_class, type_class, ba_check, |
153 | NULL, complain); | |
7993382e | 154 | if (!same_p && !binfo) |
8d08fdba | 155 | { |
00a17e31 | 156 | /* Try base to derived conversion. */ |
22854930 PC |
157 | binfo = lookup_base (type_class, intype_class, ba_check, |
158 | NULL, complain); | |
8d08fdba MS |
159 | code = MINUS_EXPR; |
160 | } | |
338d90b8 NS |
161 | if (binfo == error_mark_node) |
162 | return error_mark_node; | |
7993382e | 163 | if (binfo || same_p) |
8d08fdba | 164 | { |
7993382e | 165 | if (binfo) |
4b978f96 | 166 | expr = build_base_path (code, expr, binfo, 0, complain); |
00a17e31 | 167 | /* Add any qualifier conversions. */ |
7993382e | 168 | return build_nop (type, expr); |
8d08fdba MS |
169 | } |
170 | } | |
8d08fdba | 171 | |
a5ac359a | 172 | if (TYPE_PTRMEMFUNC_P (type)) |
28cbf42c | 173 | { |
4b978f96 PC |
174 | if (complain & tf_error) |
175 | error_at (loc, "cannot convert %qE from type %qT to type %qT", | |
176 | expr, intype, type); | |
a5ac359a MM |
177 | return error_mark_node; |
178 | } | |
b928a651 | 179 | |
a5ac359a MM |
180 | return build_nop (type, expr); |
181 | } | |
66b1156a | 182 | else if ((TYPE_PTRDATAMEM_P (type) && TYPE_PTRDATAMEM_P (intype)) |
6e03b280 OW |
183 | || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype))) |
184 | return convert_ptrmem (type, expr, /*allow_inverse_p=*/false, | |
4b978f96 | 185 | /*c_cast_p=*/false, complain); |
d8f8dca1 MM |
186 | else if (TYPE_PTRMEMFUNC_P (intype)) |
187 | { | |
d6b4ea85 MM |
188 | if (!warn_pmf2ptr) |
189 | { | |
190 | if (TREE_CODE (expr) == PTRMEM_CST) | |
4b978f96 PC |
191 | return cp_convert_to_pointer (type, PTRMEM_CST_MEMBER (expr), |
192 | complain); | |
d6b4ea85 MM |
193 | else if (TREE_CODE (expr) == OFFSET_REF) |
194 | { | |
195 | tree object = TREE_OPERAND (expr, 0); | |
196 | return get_member_function_from_ptrfunc (&object, | |
89fcabaf | 197 | TREE_OPERAND (expr, 1), |
4b978f96 | 198 | complain); |
d6b4ea85 MM |
199 | } |
200 | } | |
bc51de9c PC |
201 | if (complain & tf_error) |
202 | error_at (loc, "cannot convert %qE from type %qT to type %qT", | |
203 | expr, intype, type); | |
d8f8dca1 MM |
204 | return error_mark_node; |
205 | } | |
8d08fdba | 206 | |
33c2474d | 207 | if (null_ptr_cst_p (expr)) |
8d08fdba | 208 | { |
d8f8dca1 | 209 | if (TYPE_PTRMEMFUNC_P (type)) |
08e17d9d | 210 | return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr, 0, |
4b978f96 | 211 | /*c_cast_p=*/false, complain); |
cd8ed629 | 212 | |
f61af651 PC |
213 | if (complain & tf_warning) |
214 | maybe_warn_zero_as_null_pointer_constant (expr, loc); | |
215 | ||
e3692e02 PC |
216 | /* A NULL pointer-to-data-member is represented by -1, not by |
217 | zero. */ | |
218 | tree val = (TYPE_PTRDATAMEM_P (type) | |
219 | ? build_int_cst_type (type, -1) | |
220 | : build_int_cst (type, 0)); | |
221 | ||
222 | return (TREE_SIDE_EFFECTS (expr) | |
223 | ? build2 (COMPOUND_EXPR, type, expr, val) : val); | |
8d08fdba | 224 | } |
66b1156a | 225 | else if (TYPE_PTRMEM_P (type) && INTEGRAL_CODE_P (form)) |
201fbb7f | 226 | { |
4b978f96 PC |
227 | if (complain & tf_error) |
228 | error_at (loc, "invalid conversion from %qT to %qT", intype, type); | |
201fbb7f GDR |
229 | return error_mark_node; |
230 | } | |
8d08fdba | 231 | |
2986ae00 | 232 | if (INTEGRAL_CODE_P (form)) |
8d08fdba | 233 | { |
f5963e61 | 234 | if (TYPE_PRECISION (intype) == POINTER_SIZE) |
8d08fdba | 235 | return build1 (CONVERT_EXPR, type, expr); |
4b978f96 PC |
236 | expr = cp_convert (c_common_type_for_size (POINTER_SIZE, 0), expr, |
237 | complain); | |
8dc2b103 NS |
238 | /* Modes may be different but sizes should be the same. There |
239 | is supposed to be some integral type that is the same width | |
240 | as a pointer. */ | |
241 | gcc_assert (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (expr))) | |
242 | == GET_MODE_SIZE (TYPE_MODE (type))); | |
c8094d83 | 243 | |
8d08fdba MS |
244 | return convert_to_pointer (type, expr); |
245 | } | |
246 | ||
e6e174e5 | 247 | if (type_unknown_p (expr)) |
4b978f96 | 248 | return instantiate_type (type, expr, complain); |
e6e174e5 | 249 | |
4b978f96 PC |
250 | if (complain & tf_error) |
251 | error_at (loc, "cannot convert %qE from type %qT to type %qT", | |
252 | expr, intype, type); | |
8d08fdba MS |
253 | return error_mark_node; |
254 | } | |
255 | ||
256 | /* Like convert, except permit conversions to take place which | |
257 | are not normally allowed due to access restrictions | |
258 | (such as conversion from sub-type to private super-type). */ | |
e92cc029 | 259 | |
8d08fdba | 260 | static tree |
4b978f96 | 261 | convert_to_pointer_force (tree type, tree expr, tsubst_flags_t complain) |
8d08fdba | 262 | { |
926ce8bd KH |
263 | tree intype = TREE_TYPE (expr); |
264 | enum tree_code form = TREE_CODE (intype); | |
c8094d83 | 265 | |
8d08fdba MS |
266 | if (form == POINTER_TYPE) |
267 | { | |
268 | intype = TYPE_MAIN_VARIANT (intype); | |
269 | ||
270 | if (TYPE_MAIN_VARIANT (type) != intype | |
271 | && TREE_CODE (TREE_TYPE (type)) == RECORD_TYPE | |
9e1e64ec PC |
272 | && MAYBE_CLASS_TYPE_P (TREE_TYPE (type)) |
273 | && MAYBE_CLASS_TYPE_P (TREE_TYPE (intype)) | |
8d08fdba MS |
274 | && TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE) |
275 | { | |
276 | enum tree_code code = PLUS_EXPR; | |
338d90b8 NS |
277 | tree binfo; |
278 | ||
279 | binfo = lookup_base (TREE_TYPE (intype), TREE_TYPE (type), | |
22854930 | 280 | ba_unique, NULL, complain); |
338d90b8 | 281 | if (!binfo) |
8d08fdba | 282 | { |
338d90b8 | 283 | binfo = lookup_base (TREE_TYPE (type), TREE_TYPE (intype), |
22854930 | 284 | ba_unique, NULL, complain); |
338d90b8 | 285 | code = MINUS_EXPR; |
8d08fdba | 286 | } |
338d90b8 NS |
287 | if (binfo == error_mark_node) |
288 | return error_mark_node; | |
289 | if (binfo) | |
8d08fdba | 290 | { |
4b978f96 | 291 | expr = build_base_path (code, expr, binfo, 0, complain); |
0cbd7506 MS |
292 | if (expr == error_mark_node) |
293 | return error_mark_node; | |
00a17e31 | 294 | /* Add any qualifier conversions. */ |
338d90b8 NS |
295 | if (!same_type_p (TREE_TYPE (TREE_TYPE (expr)), |
296 | TREE_TYPE (type))) | |
7993382e | 297 | expr = build_nop (type, expr); |
338d90b8 | 298 | return expr; |
8d08fdba | 299 | } |
8d08fdba | 300 | } |
8d08fdba MS |
301 | } |
302 | ||
4b978f96 | 303 | return cp_convert_to_pointer (type, expr, complain); |
8d08fdba MS |
304 | } |
305 | ||
306 | /* We are passing something to a function which requires a reference. | |
307 | The type we are interested in is in TYPE. The initial | |
308 | value we have to begin with is in ARG. | |
309 | ||
310 | FLAGS controls how we manage access checking. | |
08ac397c JM |
311 | DIRECT_BIND in FLAGS controls how any temporaries are generated. |
312 | If DIRECT_BIND is set, DECL is the reference we're binding to. */ | |
e92cc029 | 313 | |
8d08fdba | 314 | static tree |
4b978f96 PC |
315 | build_up_reference (tree type, tree arg, int flags, tree decl, |
316 | tsubst_flags_t complain) | |
8d08fdba | 317 | { |
eb66be0e | 318 | tree rval; |
8926095f | 319 | tree argtype = TREE_TYPE (arg); |
8d08fdba | 320 | tree target_type = TREE_TYPE (type); |
8d08fdba | 321 | |
50bc768d | 322 | gcc_assert (TREE_CODE (type) == REFERENCE_TYPE); |
8d08fdba | 323 | |
eb66be0e | 324 | if ((flags & DIRECT_BIND) && ! real_lvalue_p (arg)) |
8d08fdba | 325 | { |
08ac397c JM |
326 | /* Create a new temporary variable. We can't just use a TARGET_EXPR |
327 | here because it needs to live as long as DECL. */ | |
eb66be0e | 328 | tree targ = arg; |
08ac397c | 329 | |
efd7ad5c | 330 | arg = make_temporary_var_for_ref_to_temp (decl, target_type); |
8d1e67c6 MM |
331 | |
332 | /* Process the initializer for the declaration. */ | |
9a3b49ac | 333 | DECL_INITIAL (arg) = targ; |
d174af6c | 334 | cp_finish_decl (arg, targ, /*init_const_expr_p=*/false, NULL_TREE, |
c37dc68e | 335 | LOOKUP_ONLYCONVERTING|DIRECT_BIND); |
e349ee73 | 336 | } |
eb66be0e | 337 | else if (!(flags & DIRECT_BIND) && ! lvalue_p (arg)) |
81bd268c | 338 | return get_target_expr_sfinae (arg, complain); |
e349ee73 | 339 | |
08ac397c | 340 | /* If we had a way to wrap this up, and say, if we ever needed its |
d2e5ee5c MS |
341 | address, transform all occurrences of the register, into a memory |
342 | reference we could win better. */ | |
81bd268c | 343 | rval = cp_build_addr_expr (arg, complain); |
162bc98d JM |
344 | if (rval == error_mark_node) |
345 | return error_mark_node; | |
346 | ||
6633d636 MS |
347 | if ((flags & LOOKUP_PROTECT) |
348 | && TYPE_MAIN_VARIANT (argtype) != TYPE_MAIN_VARIANT (target_type) | |
9e1e64ec PC |
349 | && MAYBE_CLASS_TYPE_P (argtype) |
350 | && MAYBE_CLASS_TYPE_P (target_type)) | |
6633d636 | 351 | { |
2db1ab2d | 352 | /* We go through lookup_base for the access control. */ |
22854930 PC |
353 | tree binfo = lookup_base (argtype, target_type, ba_check, |
354 | NULL, complain); | |
6633d636 MS |
355 | if (binfo == error_mark_node) |
356 | return error_mark_node; | |
357 | if (binfo == NULL_TREE) | |
358 | return error_not_base_type (target_type, argtype); | |
4b978f96 | 359 | rval = build_base_path (PLUS_EXPR, rval, binfo, 1, complain); |
6633d636 | 360 | } |
eb66be0e MS |
361 | else |
362 | rval | |
4b978f96 PC |
363 | = convert_to_pointer_force (build_pointer_type (target_type), |
364 | rval, complain); | |
7993382e | 365 | return build_nop (type, rval); |
8d08fdba MS |
366 | } |
367 | ||
08aead78 NS |
368 | /* Subroutine of convert_to_reference. REFTYPE is the target reference type. |
369 | INTYPE is the original rvalue type and DECL is an optional _DECL node | |
370 | for diagnostics. | |
c8094d83 | 371 | |
08aead78 NS |
372 | [dcl.init.ref] says that if an rvalue is used to |
373 | initialize a reference, then the reference must be to a | |
374 | non-volatile const type. */ | |
375 | ||
376 | static void | |
76545796 | 377 | diagnose_ref_binding (location_t loc, tree reftype, tree intype, tree decl) |
08aead78 NS |
378 | { |
379 | tree ttl = TREE_TYPE (reftype); | |
c8094d83 | 380 | |
08aead78 NS |
381 | if (!CP_TYPE_CONST_NON_VOLATILE_P (ttl)) |
382 | { | |
383 | const char *msg; | |
384 | ||
385 | if (CP_TYPE_VOLATILE_P (ttl) && decl) | |
f25a2b52 SZ |
386 | msg = G_("initialization of volatile reference type %q#T from " |
387 | "rvalue of type %qT"); | |
08aead78 | 388 | else if (CP_TYPE_VOLATILE_P (ttl)) |
f25a2b52 SZ |
389 | msg = G_("conversion to volatile reference type %q#T " |
390 | "from rvalue of type %qT"); | |
08aead78 | 391 | else if (decl) |
f25a2b52 SZ |
392 | msg = G_("initialization of non-const reference type %q#T from " |
393 | "rvalue of type %qT"); | |
08aead78 | 394 | else |
f25a2b52 SZ |
395 | msg = G_("conversion to non-const reference type %q#T from " |
396 | "rvalue of type %qT"); | |
08aead78 | 397 | |
5a3c9cf2 | 398 | permerror (loc, msg, reftype, intype); |
08aead78 NS |
399 | } |
400 | } | |
401 | ||
8d08fdba MS |
402 | /* For C++: Only need to do one-level references, but cannot |
403 | get tripped up on signed/unsigned differences. | |
404 | ||
a4443a08 MS |
405 | DECL is either NULL_TREE or the _DECL node for a reference that is being |
406 | initialized. It can be error_mark_node if we don't know the _DECL but | |
407 | we know it's an initialization. */ | |
8d08fdba | 408 | |
8d08fdba | 409 | tree |
b746c5dc | 410 | convert_to_reference (tree reftype, tree expr, int convtype, |
4b978f96 | 411 | int flags, tree decl, tsubst_flags_t complain) |
8d08fdba | 412 | { |
926ce8bd KH |
413 | tree type = TYPE_MAIN_VARIANT (TREE_TYPE (reftype)); |
414 | tree intype; | |
8d08fdba | 415 | tree rval = NULL_TREE; |
8ccc31eb | 416 | tree rval_as_conversion = NULL_TREE; |
a5ac359a | 417 | bool can_convert_intype_to_type; |
8400e75e | 418 | location_t loc = EXPR_LOC_OR_LOC (expr, input_location); |
8ccc31eb | 419 | |
c8094d83 | 420 | if (TREE_CODE (type) == FUNCTION_TYPE |
2303a079 | 421 | && TREE_TYPE (expr) == unknown_type_node) |
b40e334f | 422 | expr = instantiate_type (type, expr, complain); |
a723baf1 MM |
423 | |
424 | if (expr == error_mark_node) | |
425 | return error_mark_node; | |
426 | ||
427 | intype = TREE_TYPE (expr); | |
e6e174e5 | 428 | |
50bc768d | 429 | gcc_assert (TREE_CODE (intype) != REFERENCE_TYPE); |
d149fba0 | 430 | gcc_assert (TREE_CODE (reftype) == REFERENCE_TYPE); |
8d08fdba | 431 | |
8d08fdba MS |
432 | intype = TYPE_MAIN_VARIANT (intype); |
433 | ||
53db1bc0 | 434 | can_convert_intype_to_type = can_convert_standard (type, intype, complain); |
b40e334f | 435 | |
a5ac359a | 436 | if (!can_convert_intype_to_type |
9e1e64ec | 437 | && (convtype & CONV_IMPLICIT) && MAYBE_CLASS_TYPE_P (intype) |
8ccc31eb MS |
438 | && ! (flags & LOOKUP_NO_CONVERSION)) |
439 | { | |
440 | /* Look for a user-defined conversion to lvalue that we can use. */ | |
441 | ||
277294d7 | 442 | rval_as_conversion |
7993382e | 443 | = build_type_conversion (reftype, expr); |
8ccc31eb MS |
444 | |
445 | if (rval_as_conversion && rval_as_conversion != error_mark_node | |
446 | && real_lvalue_p (rval_as_conversion)) | |
447 | { | |
448 | expr = rval_as_conversion; | |
449 | rval_as_conversion = NULL_TREE; | |
450 | intype = type; | |
a5ac359a | 451 | can_convert_intype_to_type = 1; |
8ccc31eb MS |
452 | } |
453 | } | |
454 | ||
53db1bc0 JM |
455 | if (((convtype & CONV_STATIC) |
456 | && can_convert_standard (intype, type, complain)) | |
a5ac359a | 457 | || ((convtype & CONV_IMPLICIT) && can_convert_intype_to_type)) |
8d08fdba | 458 | { |
4b978f96 PC |
459 | { |
460 | tree ttl = TREE_TYPE (reftype); | |
461 | tree ttr = lvalue_type (expr); | |
8d08fdba | 462 | |
76545796 | 463 | if ((complain & tf_error) |
4b978f96 | 464 | && ! real_lvalue_p (expr)) |
76545796 | 465 | diagnose_ref_binding (loc, reftype, intype, decl); |
c8094d83 | 466 | |
4b978f96 PC |
467 | if (! (convtype & CONV_CONST) |
468 | && !at_least_as_qualified_p (ttl, ttr)) | |
469 | { | |
470 | if (complain & tf_error) | |
471 | permerror (loc, "conversion from %qT to %qT discards qualifiers", | |
472 | ttr, reftype); | |
473 | else | |
474 | return error_mark_node; | |
475 | } | |
476 | } | |
8926095f | 477 | |
4b978f96 | 478 | return build_up_reference (reftype, expr, flags, decl, complain); |
8d08fdba | 479 | } |
21474714 | 480 | else if ((convtype & CONV_REINTERPRET) && lvalue_p (expr)) |
8926095f MS |
481 | { |
482 | /* When casting an lvalue to a reference type, just convert into | |
483 | a pointer to the new type and deference it. This is allowed | |
a28e3c7f | 484 | by San Diego WP section 5.2.9 paragraph 12, though perhaps it |
8926095f | 485 | should be done directly (jason). (int &)ri ---> *(int*)&ri */ |
a28e3c7f | 486 | |
59be0cdd | 487 | /* B* bp; A& ar = (A&)bp; is valid, but it's probably not what they |
0cbd7506 | 488 | meant. */ |
4b978f96 | 489 | if ((complain & tf_warning) |
50e10fa8 | 490 | && TYPE_PTR_P (intype) |
96d84882 PB |
491 | && (comptypes (TREE_TYPE (intype), type, |
492 | COMPARE_BASE | COMPARE_DERIVED))) | |
5a3c9cf2 PC |
493 | warning_at (loc, 0, "casting %qT to %qT does not dereference pointer", |
494 | intype, reftype); | |
c8094d83 | 495 | |
4b978f96 | 496 | rval = cp_build_addr_expr (expr, complain); |
8926095f | 497 | if (rval != error_mark_node) |
3c215895 | 498 | rval = convert_force (build_pointer_type (TREE_TYPE (reftype)), |
4b978f96 | 499 | rval, 0, complain); |
8926095f | 500 | if (rval != error_mark_node) |
7177d104 | 501 | rval = build1 (NOP_EXPR, reftype, rval); |
8926095f | 502 | } |
277294d7 | 503 | else |
faf5394a MS |
504 | { |
505 | rval = convert_for_initialization (NULL_TREE, type, expr, flags, | |
4b978f96 | 506 | ICR_CONVERTING, 0, 0, complain); |
09ad2917 DD |
507 | if (rval == NULL_TREE || rval == error_mark_node) |
508 | return rval; | |
76545796 PC |
509 | if (complain & tf_error) |
510 | diagnose_ref_binding (loc, reftype, intype, decl); | |
4b978f96 | 511 | rval = build_up_reference (reftype, rval, flags, decl, complain); |
faf5394a | 512 | } |
8d08fdba MS |
513 | |
514 | if (rval) | |
515 | { | |
e92cc029 | 516 | /* If we found a way to convert earlier, then use it. */ |
8d08fdba MS |
517 | return rval; |
518 | } | |
519 | ||
4b978f96 | 520 | if (complain & tf_error) |
5a3c9cf2 | 521 | error_at (loc, "cannot convert type %qT to type %qT", intype, reftype); |
878cd289 | 522 | |
8d08fdba MS |
523 | return error_mark_node; |
524 | } | |
525 | ||
526 | /* We are using a reference VAL for its value. Bash that reference all the | |
e92cc029 MS |
527 | way down to its lowest form. */ |
528 | ||
8d08fdba | 529 | tree |
b746c5dc | 530 | convert_from_reference (tree val) |
8d08fdba | 531 | { |
4e3f6d85 JM |
532 | if (TREE_TYPE (val) |
533 | && TREE_CODE (TREE_TYPE (val)) == REFERENCE_TYPE) | |
db24eb1f | 534 | { |
cd41d410 | 535 | tree t = TREE_TYPE (TREE_TYPE (val)); |
db24eb1f | 536 | tree ref = build1 (INDIRECT_REF, t, val); |
c8094d83 | 537 | |
e3ae330d | 538 | mark_exp_read (val); |
db24eb1f NS |
539 | /* We *must* set TREE_READONLY when dereferencing a pointer to const, |
540 | so that we get the proper error message if the result is used | |
541 | to assign to. Also, &* is supposed to be a no-op. */ | |
542 | TREE_READONLY (ref) = CP_TYPE_CONST_P (t); | |
543 | TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t); | |
544 | TREE_SIDE_EFFECTS (ref) | |
545 | = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (val)); | |
db24eb1f NS |
546 | val = ref; |
547 | } | |
c8094d83 | 548 | |
8d08fdba MS |
549 | return val; |
550 | } | |
f7b9026e JM |
551 | |
552 | /* Really perform an lvalue-to-rvalue conversion, including copying an | |
553 | argument of class type into a temporary. */ | |
554 | ||
555 | tree | |
574cfaa4 | 556 | force_rvalue (tree expr, tsubst_flags_t complain) |
f7b9026e | 557 | { |
574cfaa4 JM |
558 | tree type = TREE_TYPE (expr); |
559 | if (MAYBE_CLASS_TYPE_P (type) && TREE_CODE (expr) != TARGET_EXPR) | |
560 | { | |
9771b263 | 561 | vec<tree, va_gc> *args = make_tree_vector_single (expr); |
574cfaa4 JM |
562 | expr = build_special_member_call (NULL_TREE, complete_ctor_identifier, |
563 | &args, type, LOOKUP_NORMAL, complain); | |
564 | release_tree_vector (args); | |
565 | expr = build_cplus_new (type, expr, complain); | |
566 | } | |
f7b9026e | 567 | else |
89fcabaf | 568 | expr = decay_conversion (expr, complain); |
f7b9026e JM |
569 | |
570 | return expr; | |
571 | } | |
9771799c | 572 | |
8d08fdba | 573 | \f |
9e115cec JM |
574 | /* If EXPR and ORIG are INTEGER_CSTs, return a version of EXPR that has |
575 | TREE_OVERFLOW set only if it is set in ORIG. Otherwise, return EXPR | |
576 | unchanged. */ | |
577 | ||
578 | static tree | |
579 | ignore_overflows (tree expr, tree orig) | |
580 | { | |
581 | if (TREE_CODE (expr) == INTEGER_CST | |
582 | && TREE_CODE (orig) == INTEGER_CST | |
583 | && TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig)) | |
584 | { | |
585 | gcc_assert (!TREE_OVERFLOW (orig)); | |
586 | /* Ensure constant sharing. */ | |
807e902e | 587 | expr = wide_int_to_tree (TREE_TYPE (expr), expr); |
9e115cec JM |
588 | } |
589 | return expr; | |
590 | } | |
591 | ||
592 | /* Fold away simple conversions, but make sure TREE_OVERFLOW is set | |
593 | properly. */ | |
9771799c JM |
594 | |
595 | tree | |
596 | cp_fold_convert (tree type, tree expr) | |
597 | { | |
fb899e32 JM |
598 | tree conv; |
599 | if (TREE_TYPE (expr) == type) | |
600 | conv = expr; | |
601 | else if (TREE_CODE (expr) == PTRMEM_CST) | |
602 | { | |
603 | /* Avoid wrapping a PTRMEM_CST in NOP_EXPR. */ | |
604 | conv = copy_node (expr); | |
605 | TREE_TYPE (conv) = type; | |
606 | } | |
607 | else | |
608 | { | |
609 | conv = fold_convert (type, expr); | |
610 | conv = ignore_overflows (conv, expr); | |
611 | } | |
9e115cec | 612 | return conv; |
9771799c JM |
613 | } |
614 | ||
37c46b43 MS |
615 | /* C++ conversions, preference to static cast conversions. */ |
616 | ||
617 | tree | |
4b978f96 | 618 | cp_convert (tree type, tree expr, tsubst_flags_t complain) |
37c46b43 | 619 | { |
4b978f96 | 620 | return ocp_convert (type, expr, CONV_OLD_CONVERT, LOOKUP_NORMAL, complain); |
37c46b43 MS |
621 | } |
622 | ||
07231d4f MLI |
623 | /* C++ equivalent of convert_and_check but using cp_convert as the |
624 | conversion function. | |
625 | ||
626 | Convert EXPR to TYPE, warning about conversion problems with constants. | |
627 | Invoke this function on every expression that is converted implicitly, | |
628 | i.e. because of language rules and not because of an explicit cast. */ | |
629 | ||
630 | tree | |
4b978f96 | 631 | cp_convert_and_check (tree type, tree expr, tsubst_flags_t complain) |
07231d4f MLI |
632 | { |
633 | tree result; | |
634 | ||
635 | if (TREE_TYPE (expr) == type) | |
636 | return expr; | |
637 | ||
4b978f96 | 638 | result = cp_convert (type, expr, complain); |
07231d4f | 639 | |
4b978f96 | 640 | if ((complain & tf_warning) |
da834cfc JM |
641 | && c_inhibit_evaluation_warnings == 0) |
642 | { | |
643 | tree folded = maybe_constant_value (expr); | |
644 | tree stripped = folded; | |
d2504d68 PC |
645 | tree folded_result |
646 | = folded != expr ? cp_convert (type, folded, complain) : result; | |
da834cfc JM |
647 | |
648 | /* maybe_constant_value wraps an INTEGER_CST with TREE_OVERFLOW in a | |
649 | NOP_EXPR so that it isn't TREE_CONSTANT anymore. */ | |
650 | STRIP_NOPS (stripped); | |
651 | ||
652 | if (!TREE_OVERFLOW_P (stripped) | |
653 | && folded_result != error_mark_node) | |
68fca595 MP |
654 | warnings_for_convert_and_check (input_location, type, folded, |
655 | folded_result); | |
da834cfc | 656 | } |
07231d4f MLI |
657 | |
658 | return result; | |
659 | } | |
660 | ||
878cd289 MS |
661 | /* Conversion... |
662 | ||
663 | FLAGS indicates how we should behave. */ | |
664 | ||
8d08fdba | 665 | tree |
4b978f96 PC |
666 | ocp_convert (tree type, tree expr, int convtype, int flags, |
667 | tsubst_flags_t complain) | |
8d08fdba | 668 | { |
926ce8bd KH |
669 | tree e = expr; |
670 | enum tree_code code = TREE_CODE (type); | |
4de67c26 | 671 | const char *invalid_conv_diag; |
40449a90 | 672 | tree e1; |
8400e75e | 673 | location_t loc = EXPR_LOC_OR_LOC (expr, input_location); |
8d08fdba | 674 | |
a5ac359a | 675 | if (error_operand_p (e) || type == error_mark_node) |
8d08fdba | 676 | return error_mark_node; |
a4443a08 | 677 | |
5d73aa63 MM |
678 | complete_type (type); |
679 | complete_type (TREE_TYPE (expr)); | |
680 | ||
4de67c26 JM |
681 | if ((invalid_conv_diag |
682 | = targetm.invalid_conversion (TREE_TYPE (expr), type))) | |
683 | { | |
4b978f96 PC |
684 | if (complain & tf_error) |
685 | error (invalid_conv_diag); | |
4de67c26 JM |
686 | return error_mark_node; |
687 | } | |
688 | ||
fa2200cb | 689 | /* FIXME remove when moving to c_fully_fold model. */ |
9783ae5a PP |
690 | if (!CLASS_TYPE_P (type)) |
691 | e = scalar_constant_value (e); | |
88274c4d JM |
692 | if (error_operand_p (e)) |
693 | return error_mark_node; | |
9c0d0367 | 694 | |
9e1e64ec | 695 | if (MAYBE_CLASS_TYPE_P (type) && (convtype & CONV_FORCE_TEMP)) |
8ccc31eb | 696 | /* We need a new temporary; don't take this shortcut. */; |
0fcedd9c | 697 | else if (same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (e))) |
01240200 | 698 | { |
3bfdc719 | 699 | if (same_type_p (type, TREE_TYPE (e))) |
01240200 MM |
700 | /* The call to fold will not always remove the NOP_EXPR as |
701 | might be expected, since if one of the types is a typedef; | |
34cd5ae7 | 702 | the comparison in fold is just equality of pointers, not a |
96d84882 | 703 | call to comptypes. We don't call fold in this case because |
953360c8 MM |
704 | that can result in infinite recursion; fold will call |
705 | convert, which will call ocp_convert, etc. */ | |
706 | return e; | |
a04678ca | 707 | /* For complex data types, we need to perform componentwise |
0cbd7506 | 708 | conversion. */ |
a04678ca | 709 | else if (TREE_CODE (type) == COMPLEX_TYPE) |
0cbd7506 | 710 | return fold_if_not_in_template (convert_to_complex (type, e)); |
b55b02ea | 711 | else if (VECTOR_TYPE_P (type)) |
d5a1053a | 712 | return fold_if_not_in_template (convert_to_vector (type, e)); |
4e8dca1c JM |
713 | else if (TREE_CODE (e) == TARGET_EXPR) |
714 | { | |
715 | /* Don't build a NOP_EXPR of class type. Instead, change the | |
0fcedd9c | 716 | type of the temporary. */ |
4e8dca1c JM |
717 | TREE_TYPE (e) = TREE_TYPE (TARGET_EXPR_SLOT (e)) = type; |
718 | return e; | |
719 | } | |
01240200 | 720 | else |
8dc2b103 NS |
721 | { |
722 | /* We shouldn't be treating objects of ADDRESSABLE type as | |
723 | rvalues. */ | |
724 | gcc_assert (!TREE_ADDRESSABLE (type)); | |
455f19cb | 725 | return fold_if_not_in_template (build_nop (type, e)); |
8dc2b103 | 726 | } |
01240200 MM |
727 | } |
728 | ||
40449a90 SL |
729 | e1 = targetm.convert_to_type (type, e); |
730 | if (e1) | |
731 | return e1; | |
732 | ||
a4443a08 | 733 | if (code == VOID_TYPE && (convtype & CONV_STATIC)) |
848b92e1 | 734 | { |
4b978f96 | 735 | e = convert_to_void (e, ICV_CAST, complain); |
66543169 | 736 | return e; |
848b92e1 | 737 | } |
a4443a08 | 738 | |
2986ae00 | 739 | if (INTEGRAL_CODE_P (code)) |
8d08fdba | 740 | { |
f0e01782 | 741 | tree intype = TREE_TYPE (e); |
9e115cec | 742 | tree converted; |
b13e752f MLI |
743 | |
744 | if (TREE_CODE (type) == ENUMERAL_TYPE) | |
745 | { | |
746 | /* enum = enum, enum = int, enum = float, (enum)pointer are all | |
747 | errors. */ | |
748 | if (((INTEGRAL_OR_ENUMERATION_TYPE_P (intype) | |
0cbd7506 | 749 | || TREE_CODE (intype) == REAL_TYPE) |
b6ab6892 | 750 | && ! (convtype & CONV_STATIC)) |
50e10fa8 | 751 | || TYPE_PTR_P (intype)) |
b13e752f | 752 | { |
4b978f96 | 753 | if (complain & tf_error) |
5a3c9cf2 | 754 | permerror (loc, "conversion from %q#T to %q#T", intype, type); |
4b978f96 | 755 | else |
b13e752f MLI |
756 | return error_mark_node; |
757 | } | |
758 | ||
759 | /* [expr.static.cast] | |
760 | ||
761 | 8. A value of integral or enumeration type can be explicitly | |
762 | converted to an enumeration type. The value is unchanged if | |
763 | the original value is within the range of the enumeration | |
764 | values. Otherwise, the resulting enumeration value is | |
765 | unspecified. */ | |
4b978f96 | 766 | if ((complain & tf_warning) |
8d0d1915 | 767 | && TREE_CODE (e) == INTEGER_CST |
0ffc4683 | 768 | && ENUM_UNDERLYING_TYPE (type) |
8d0d1915 | 769 | && !int_fits_type_p (e, ENUM_UNDERLYING_TYPE (type))) |
5a3c9cf2 PC |
770 | warning_at (loc, OPT_Wconversion, |
771 | "the result of the conversion is unspecified because " | |
772 | "%qE is outside the range of type %qT", | |
773 | expr, type); | |
8d08fdba | 774 | } |
9e1e64ec | 775 | if (MAYBE_CLASS_TYPE_P (intype)) |
8d08fdba MS |
776 | { |
777 | tree rval; | |
7993382e | 778 | rval = build_type_conversion (type, e); |
00595019 MS |
779 | if (rval) |
780 | return rval; | |
4b978f96 | 781 | if (complain & tf_error) |
5a3c9cf2 | 782 | error_at (loc, "%q#T used where a %qT was expected", intype, type); |
8d08fdba MS |
783 | return error_mark_node; |
784 | } | |
2986ae00 | 785 | if (code == BOOLEAN_TYPE) |
1ee44b26 | 786 | { |
50e10fa8 | 787 | if (VOID_TYPE_P (intype)) |
5a3c9cf2 | 788 | { |
4b978f96 PC |
789 | if (complain & tf_error) |
790 | error_at (loc, | |
791 | "could not convert %qE from %<void%> to %<bool%>", | |
792 | expr); | |
5a3c9cf2 PC |
793 | return error_mark_node; |
794 | } | |
795 | ||
1ee44b26 JM |
796 | /* We can't implicitly convert a scoped enum to bool, so convert |
797 | to the underlying type first. */ | |
798 | if (SCOPED_ENUM_P (intype) && (convtype & CONV_STATIC)) | |
55b13820 | 799 | e = build_nop (ENUM_UNDERLYING_TYPE (intype), e); |
1ee44b26 JM |
800 | return cp_truthvalue_conversion (e); |
801 | } | |
1998463c | 802 | |
9e115cec JM |
803 | converted = fold_if_not_in_template (convert_to_integer (type, e)); |
804 | ||
805 | /* Ignore any integer overflow caused by the conversion. */ | |
806 | return ignore_overflows (converted, e); | |
8d08fdba | 807 | } |
5116acc6 | 808 | if (NULLPTR_TYPE_P (type) && e && null_ptr_cst_p (e)) |
30b07d03 PC |
809 | { |
810 | if (complain & tf_warning) | |
811 | maybe_warn_zero_as_null_pointer_constant (e, loc); | |
812 | return nullptr_node; | |
813 | } | |
66b1156a | 814 | if (POINTER_TYPE_P (type) || TYPE_PTRMEM_P (type)) |
4b978f96 | 815 | return fold_if_not_in_template (cp_convert_to_pointer (type, e, complain)); |
bb37c4a5 | 816 | if (code == VECTOR_TYPE) |
037cc9c5 FJ |
817 | { |
818 | tree in_vtype = TREE_TYPE (e); | |
9e1e64ec | 819 | if (MAYBE_CLASS_TYPE_P (in_vtype)) |
037cc9c5 FJ |
820 | { |
821 | tree ret_val; | |
822 | ret_val = build_type_conversion (type, e); | |
0cbd7506 MS |
823 | if (ret_val) |
824 | return ret_val; | |
4b978f96 PC |
825 | if (complain & tf_error) |
826 | error_at (loc, "%q#T used where a %qT was expected", | |
827 | in_vtype, type); | |
0cbd7506 | 828 | return error_mark_node; |
037cc9c5 | 829 | } |
455f19cb | 830 | return fold_if_not_in_template (convert_to_vector (type, e)); |
037cc9c5 | 831 | } |
37c46b43 | 832 | if (code == REAL_TYPE || code == COMPLEX_TYPE) |
8d08fdba | 833 | { |
9e1e64ec | 834 | if (MAYBE_CLASS_TYPE_P (TREE_TYPE (e))) |
8d08fdba MS |
835 | { |
836 | tree rval; | |
7993382e | 837 | rval = build_type_conversion (type, e); |
8d08fdba MS |
838 | if (rval) |
839 | return rval; | |
4b978f96 PC |
840 | else if (complain & tf_error) |
841 | error_at (loc, | |
842 | "%q#T used where a floating point value was expected", | |
843 | TREE_TYPE (e)); | |
8d08fdba | 844 | } |
37c46b43 | 845 | if (code == REAL_TYPE) |
455f19cb | 846 | return fold_if_not_in_template (convert_to_real (type, e)); |
37c46b43 | 847 | else if (code == COMPLEX_TYPE) |
455f19cb | 848 | return fold_if_not_in_template (convert_to_complex (type, e)); |
8d08fdba MS |
849 | } |
850 | ||
851 | /* New C++ semantics: since assignment is now based on | |
852 | memberwise copying, if the rhs type is derived from the | |
853 | lhs type, then we may still do a conversion. */ | |
9e1e64ec | 854 | if (RECORD_OR_UNION_CODE_P (code)) |
8d08fdba MS |
855 | { |
856 | tree dtype = TREE_TYPE (e); | |
db5ae43f | 857 | tree ctor = NULL_TREE; |
8d08fdba | 858 | |
8d08fdba MS |
859 | dtype = TYPE_MAIN_VARIANT (dtype); |
860 | ||
8d08fdba MS |
861 | /* Conversion between aggregate types. New C++ semantics allow |
862 | objects of derived type to be cast to objects of base type. | |
863 | Old semantics only allowed this between pointers. | |
864 | ||
865 | There may be some ambiguity between using a constructor | |
866 | vs. using a type conversion operator when both apply. */ | |
867 | ||
277294d7 | 868 | ctor = e; |
faf5394a | 869 | |
81bd268c | 870 | if (abstract_virtuals_error_sfinae (NULL_TREE, type, complain)) |
a7a64a77 | 871 | return error_mark_node; |
59e76fc6 | 872 | |
09357846 | 873 | if (BRACE_ENCLOSED_INITIALIZER_P (ctor)) |
4b978f96 | 874 | ctor = perform_implicit_conversion (type, ctor, complain); |
09357846 JM |
875 | else if ((flags & LOOKUP_ONLYCONVERTING) |
876 | && ! (CLASS_TYPE_P (dtype) && DERIVED_FROM_P (type, dtype))) | |
62c154ed JM |
877 | /* For copy-initialization, first we create a temp of the proper type |
878 | with a user-defined conversion sequence, then we direct-initialize | |
879 | the target with the temp (see [dcl.init]). */ | |
4b978f96 | 880 | ctor = build_user_type_conversion (type, ctor, flags, complain); |
5e818b93 | 881 | else |
c166b898 | 882 | { |
9771b263 | 883 | vec<tree, va_gc> *ctor_vec = make_tree_vector_single (ctor); |
c166b898 ILT |
884 | ctor = build_special_member_call (NULL_TREE, |
885 | complete_ctor_identifier, | |
886 | &ctor_vec, | |
4b978f96 | 887 | type, flags, complain); |
c166b898 ILT |
888 | release_tree_vector (ctor_vec); |
889 | } | |
277294d7 | 890 | if (ctor) |
4b978f96 | 891 | return build_cplus_new (type, ctor, complain); |
8d08fdba MS |
892 | } |
893 | ||
4b978f96 | 894 | if (complain & tf_error) |
111a28c2 DS |
895 | { |
896 | /* If the conversion failed and expr was an invalid use of pointer to | |
897 | member function, try to report a meaningful error. */ | |
d3ea4c06 | 898 | if (invalid_nonstatic_memfn_p (loc, expr, complain)) |
111a28c2 DS |
899 | /* We displayed the error message. */; |
900 | else | |
5a3c9cf2 PC |
901 | error_at (loc, "conversion from %qT to non-scalar type %qT requested", |
902 | TREE_TYPE (expr), type); | |
111a28c2 | 903 | } |
8d08fdba MS |
904 | return error_mark_node; |
905 | } | |
906 | ||
02cac427 NS |
907 | /* When an expression is used in a void context, its value is discarded and |
908 | no lvalue-rvalue and similar conversions happen [expr.static.cast/4, | |
909 | stmt.expr/1, expr.comma/1]. This permits dereferencing an incomplete type | |
910 | in a void context. The C++ standard does not define what an `access' to an | |
cd0be382 | 911 | object is, but there is reason to believe that it is the lvalue to rvalue |
02cac427 NS |
912 | conversion -- if it were not, `*&*p = 1' would violate [expr]/4 in that it |
913 | accesses `*p' not to calculate the value to be stored. But, dcl.type.cv/8 | |
914 | indicates that volatile semantics should be the same between C and C++ | |
915 | where ever possible. C leaves it implementation defined as to what | |
916 | constitutes an access to a volatile. So, we interpret `*vp' as a read of | |
917 | the volatile object `vp' points to, unless that is an incomplete type. For | |
918 | volatile references we do not do this interpretation, because that would | |
919 | make it impossible to ignore the reference return value from functions. We | |
920 | issue warnings in the confusing cases. | |
c8094d83 | 921 | |
ebeb2c24 SZ |
922 | The IMPLICIT is ICV_CAST when the user is explicitly converting an expression |
923 | to void via a cast. If an expression is being implicitly converted, IMPLICIT | |
924 | indicates the context of the implicit conversion. */ | |
02cac427 NS |
925 | |
926 | tree | |
ebeb2c24 | 927 | convert_to_void (tree expr, impl_conv_void implicit, tsubst_flags_t complain) |
02cac427 | 928 | { |
8400e75e | 929 | location_t loc = EXPR_LOC_OR_LOC (expr, input_location); |
5a3c9cf2 | 930 | |
c8094d83 | 931 | if (expr == error_mark_node |
07c88314 MM |
932 | || TREE_TYPE (expr) == error_mark_node) |
933 | return error_mark_node; | |
056928b2 | 934 | |
ebeb2c24 | 935 | if (implicit == ICV_CAST) |
9fc8dacc JJ |
936 | mark_exp_read (expr); |
937 | else | |
938 | { | |
939 | tree exprv = expr; | |
940 | ||
941 | while (TREE_CODE (exprv) == COMPOUND_EXPR) | |
942 | exprv = TREE_OPERAND (exprv, 1); | |
d84686d1 JJ |
943 | if (DECL_P (exprv) |
944 | || handled_component_p (exprv) | |
591cb3cf | 945 | || INDIRECT_REF_P (exprv)) |
9fc8dacc JJ |
946 | /* Expr is not being 'used' here, otherwise we whould have |
947 | called mark_{rl}value_use use here, which would have in turn | |
948 | called mark_exp_read. Rather, we call mark_exp_read directly | |
949 | to avoid some warnings when | |
950 | -Wunused-but-set-{variable,parameter} is in effect. */ | |
951 | mark_exp_read (exprv); | |
952 | } | |
056928b2 | 953 | |
02cac427 NS |
954 | if (!TREE_TYPE (expr)) |
955 | return expr; | |
d3ea4c06 | 956 | if (invalid_nonstatic_memfn_p (loc, expr, complain)) |
c8b2e872 | 957 | return error_mark_node; |
9f4faeae MM |
958 | if (TREE_CODE (expr) == PSEUDO_DTOR_EXPR) |
959 | { | |
5ade1ed2 | 960 | if (complain & tf_error) |
5a3c9cf2 | 961 | error_at (loc, "pseudo-destructor is not called"); |
9f4faeae MM |
962 | return error_mark_node; |
963 | } | |
b72801e2 | 964 | if (VOID_TYPE_P (TREE_TYPE (expr))) |
02cac427 NS |
965 | return expr; |
966 | switch (TREE_CODE (expr)) | |
967 | { | |
968 | case COND_EXPR: | |
969 | { | |
0cbd7506 MS |
970 | /* The two parts of a cond expr might be separate lvalues. */ |
971 | tree op1 = TREE_OPERAND (expr,1); | |
972 | tree op2 = TREE_OPERAND (expr,2); | |
cb8384a3 JM |
973 | bool side_effects = ((op1 && TREE_SIDE_EFFECTS (op1)) |
974 | || TREE_SIDE_EFFECTS (op2)); | |
ebeb2c24 | 975 | tree new_op1, new_op2; |
cb8384a3 | 976 | new_op1 = NULL_TREE; |
ebeb2c24 SZ |
977 | if (implicit != ICV_CAST && !side_effects) |
978 | { | |
cb8384a3 JM |
979 | if (op1) |
980 | new_op1 = convert_to_void (op1, ICV_SECOND_OF_COND, complain); | |
ebeb2c24 SZ |
981 | new_op2 = convert_to_void (op2, ICV_THIRD_OF_COND, complain); |
982 | } | |
983 | else | |
984 | { | |
cb8384a3 JM |
985 | if (op1) |
986 | new_op1 = convert_to_void (op1, ICV_CAST, complain); | |
ebeb2c24 SZ |
987 | new_op2 = convert_to_void (op2, ICV_CAST, complain); |
988 | } | |
c8094d83 | 989 | |
cb8384a3 | 990 | expr = build3 (COND_EXPR, TREE_TYPE (new_op2), |
f293ce4b | 991 | TREE_OPERAND (expr, 0), new_op1, new_op2); |
0cbd7506 | 992 | break; |
02cac427 | 993 | } |
c8094d83 | 994 | |
02cac427 NS |
995 | case COMPOUND_EXPR: |
996 | { | |
0cbd7506 MS |
997 | /* The second part of a compound expr contains the value. */ |
998 | tree op1 = TREE_OPERAND (expr,1); | |
ebeb2c24 SZ |
999 | tree new_op1; |
1000 | if (implicit != ICV_CAST && !TREE_NO_WARNING (expr)) | |
1001 | new_op1 = convert_to_void (op1, ICV_RIGHT_OF_COMMA, complain); | |
1002 | else | |
1003 | new_op1 = convert_to_void (op1, ICV_CAST, complain); | |
c8094d83 | 1004 | |
0cbd7506 | 1005 | if (new_op1 != op1) |
9a52d09b | 1006 | { |
f293ce4b RS |
1007 | tree t = build2 (COMPOUND_EXPR, TREE_TYPE (new_op1), |
1008 | TREE_OPERAND (expr, 0), new_op1); | |
9a52d09b MM |
1009 | expr = t; |
1010 | } | |
1011 | ||
0cbd7506 | 1012 | break; |
02cac427 | 1013 | } |
c8094d83 | 1014 | |
02cac427 NS |
1015 | case NON_LVALUE_EXPR: |
1016 | case NOP_EXPR: | |
00a17e31 | 1017 | /* These have already decayed to rvalue. */ |
02cac427 | 1018 | break; |
c8094d83 | 1019 | |
f4f206f4 | 1020 | case CALL_EXPR: /* We have a special meaning for volatile void fn(). */ |
02cac427 | 1021 | break; |
c8094d83 | 1022 | |
02cac427 NS |
1023 | case INDIRECT_REF: |
1024 | { | |
0cbd7506 MS |
1025 | tree type = TREE_TYPE (expr); |
1026 | int is_reference = TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) | |
1027 | == REFERENCE_TYPE; | |
1028 | int is_volatile = TYPE_VOLATILE (type); | |
1029 | int is_complete = COMPLETE_TYPE_P (complete_type (type)); | |
1030 | ||
bed02d89 | 1031 | /* Can't load the value if we don't know the type. */ |
0cbd7506 | 1032 | if (is_volatile && !is_complete) |
5ade1ed2 DG |
1033 | { |
1034 | if (complain & tf_warning) | |
ebeb2c24 SZ |
1035 | switch (implicit) |
1036 | { | |
1037 | case ICV_CAST: | |
5a3c9cf2 | 1038 | warning_at (loc, 0, "conversion to void will not access " |
ebeb2c24 SZ |
1039 | "object of incomplete type %qT", type); |
1040 | break; | |
1041 | case ICV_SECOND_OF_COND: | |
5a3c9cf2 | 1042 | warning_at (loc, 0, "indirection will not access object of " |
ebeb2c24 SZ |
1043 | "incomplete type %qT in second operand " |
1044 | "of conditional expression", type); | |
1045 | break; | |
1046 | case ICV_THIRD_OF_COND: | |
5a3c9cf2 | 1047 | warning_at (loc, 0, "indirection will not access object of " |
ebeb2c24 SZ |
1048 | "incomplete type %qT in third operand " |
1049 | "of conditional expression", type); | |
1050 | break; | |
1051 | case ICV_RIGHT_OF_COMMA: | |
5a3c9cf2 | 1052 | warning_at (loc, 0, "indirection will not access object of " |
ebeb2c24 SZ |
1053 | "incomplete type %qT in right operand of " |
1054 | "comma operator", type); | |
1055 | break; | |
1056 | case ICV_LEFT_OF_COMMA: | |
5a3c9cf2 | 1057 | warning_at (loc, 0, "indirection will not access object of " |
ebeb2c24 SZ |
1058 | "incomplete type %qT in left operand of " |
1059 | "comma operator", type); | |
1060 | break; | |
1061 | case ICV_STATEMENT: | |
5a3c9cf2 | 1062 | warning_at (loc, 0, "indirection will not access object of " |
ebeb2c24 SZ |
1063 | "incomplete type %qT in statement", type); |
1064 | break; | |
1065 | case ICV_THIRD_IN_FOR: | |
5a3c9cf2 | 1066 | warning_at (loc, 0, "indirection will not access object of " |
ebeb2c24 SZ |
1067 | "incomplete type %qT in for increment " |
1068 | "expression", type); | |
1069 | break; | |
1070 | default: | |
1071 | gcc_unreachable (); | |
1072 | } | |
5ade1ed2 | 1073 | } |
bed02d89 JM |
1074 | /* Don't load the value if this is an implicit dereference, or if |
1075 | the type needs to be handled by ctors/dtors. */ | |
ebeb2c24 | 1076 | else if (is_volatile && is_reference) |
5ade1ed2 DG |
1077 | { |
1078 | if (complain & tf_warning) | |
ebeb2c24 SZ |
1079 | switch (implicit) |
1080 | { | |
1081 | case ICV_CAST: | |
5a3c9cf2 | 1082 | warning_at (loc, 0, "conversion to void will not access " |
ebeb2c24 SZ |
1083 | "object of type %qT", type); |
1084 | break; | |
1085 | case ICV_SECOND_OF_COND: | |
5a3c9cf2 PC |
1086 | warning_at (loc, 0, "implicit dereference will not access " |
1087 | "object of type %qT in second operand of " | |
ebeb2c24 SZ |
1088 | "conditional expression", type); |
1089 | break; | |
1090 | case ICV_THIRD_OF_COND: | |
5a3c9cf2 PC |
1091 | warning_at (loc, 0, "implicit dereference will not access " |
1092 | "object of type %qT in third operand of " | |
ebeb2c24 SZ |
1093 | "conditional expression", type); |
1094 | break; | |
1095 | case ICV_RIGHT_OF_COMMA: | |
5a3c9cf2 PC |
1096 | warning_at (loc, 0, "implicit dereference will not access " |
1097 | "object of type %qT in right operand of " | |
ebeb2c24 SZ |
1098 | "comma operator", type); |
1099 | break; | |
1100 | case ICV_LEFT_OF_COMMA: | |
5a3c9cf2 PC |
1101 | warning_at (loc, 0, "implicit dereference will not access " |
1102 | "object of type %qT in left operand of comma " | |
1103 | "operator", type); | |
ebeb2c24 SZ |
1104 | break; |
1105 | case ICV_STATEMENT: | |
5a3c9cf2 PC |
1106 | warning_at (loc, 0, "implicit dereference will not access " |
1107 | "object of type %qT in statement", type); | |
ebeb2c24 SZ |
1108 | break; |
1109 | case ICV_THIRD_IN_FOR: | |
5a3c9cf2 PC |
1110 | warning_at (loc, 0, "implicit dereference will not access " |
1111 | "object of type %qT in for increment expression", | |
1112 | type); | |
ebeb2c24 SZ |
1113 | break; |
1114 | default: | |
1115 | gcc_unreachable (); | |
1116 | } | |
5ade1ed2 | 1117 | } |
ebeb2c24 SZ |
1118 | else if (is_volatile && TREE_ADDRESSABLE (type)) |
1119 | { | |
1120 | if (complain & tf_warning) | |
1121 | switch (implicit) | |
1122 | { | |
1123 | case ICV_CAST: | |
5a3c9cf2 | 1124 | warning_at (loc, 0, "conversion to void will not access " |
ebeb2c24 | 1125 | "object of non-trivially-copyable type %qT", |
5a3c9cf2 | 1126 | type); |
ebeb2c24 SZ |
1127 | break; |
1128 | case ICV_SECOND_OF_COND: | |
5a3c9cf2 | 1129 | warning_at (loc, 0, "indirection will not access object of " |
ebeb2c24 SZ |
1130 | "non-trivially-copyable type %qT in second " |
1131 | "operand of conditional expression", type); | |
1132 | break; | |
1133 | case ICV_THIRD_OF_COND: | |
5a3c9cf2 | 1134 | warning_at (loc, 0, "indirection will not access object of " |
ebeb2c24 SZ |
1135 | "non-trivially-copyable type %qT in third " |
1136 | "operand of conditional expression", type); | |
1137 | break; | |
1138 | case ICV_RIGHT_OF_COMMA: | |
5a3c9cf2 | 1139 | warning_at (loc, 0, "indirection will not access object of " |
ebeb2c24 SZ |
1140 | "non-trivially-copyable type %qT in right " |
1141 | "operand of comma operator", type); | |
1142 | break; | |
1143 | case ICV_LEFT_OF_COMMA: | |
5a3c9cf2 | 1144 | warning_at (loc, 0, "indirection will not access object of " |
ebeb2c24 SZ |
1145 | "non-trivially-copyable type %qT in left " |
1146 | "operand of comma operator", type); | |
1147 | break; | |
1148 | case ICV_STATEMENT: | |
5a3c9cf2 | 1149 | warning_at (loc, 0, "indirection will not access object of " |
ebeb2c24 | 1150 | "non-trivially-copyable type %qT in statement", |
5a3c9cf2 | 1151 | type); |
ebeb2c24 SZ |
1152 | break; |
1153 | case ICV_THIRD_IN_FOR: | |
5a3c9cf2 | 1154 | warning_at (loc, 0, "indirection will not access object of " |
ebeb2c24 SZ |
1155 | "non-trivially-copyable type %qT in for " |
1156 | "increment expression", type); | |
1157 | break; | |
1158 | default: | |
1159 | gcc_unreachable (); | |
1160 | } | |
1161 | } | |
bed02d89 | 1162 | if (is_reference || !is_volatile || !is_complete || TREE_ADDRESSABLE (type)) |
041d7a27 LCW |
1163 | { |
1164 | /* Emit a warning (if enabled) when the "effect-less" INDIRECT_REF | |
1165 | operation is stripped off. Note that we don't warn about | |
1166 | - an expression with TREE_NO_WARNING set. (For an example of | |
1167 | such expressions, see build_over_call in call.c.) | |
1168 | - automatic dereferencing of references, since the user cannot | |
fd4116f4 | 1169 | control it. (See also warn_if_unused_value() in c-common.c.) */ |
041d7a27 | 1170 | if (warn_unused_value |
ebeb2c24 | 1171 | && implicit != ICV_CAST |
041d7a27 LCW |
1172 | && (complain & tf_warning) |
1173 | && !TREE_NO_WARNING (expr) | |
1174 | && !is_reference) | |
5a3c9cf2 | 1175 | warning_at (loc, OPT_Wunused_value, "value computed is not used"); |
041d7a27 LCW |
1176 | expr = TREE_OPERAND (expr, 0); |
1177 | } | |
0cbd7506 MS |
1178 | |
1179 | break; | |
02cac427 | 1180 | } |
c8094d83 | 1181 | |
02cac427 NS |
1182 | case VAR_DECL: |
1183 | { | |
0cbd7506 MS |
1184 | /* External variables might be incomplete. */ |
1185 | tree type = TREE_TYPE (expr); | |
1186 | int is_complete = COMPLETE_TYPE_P (complete_type (type)); | |
1187 | ||
5ade1ed2 | 1188 | if (TYPE_VOLATILE (type) && !is_complete && (complain & tf_warning)) |
ebeb2c24 SZ |
1189 | switch (implicit) |
1190 | { | |
1191 | case ICV_CAST: | |
5a3c9cf2 | 1192 | warning_at (loc, 0, "conversion to void will not access " |
ebeb2c24 SZ |
1193 | "object %qE of incomplete type %qT", expr, type); |
1194 | break; | |
1195 | case ICV_SECOND_OF_COND: | |
5a3c9cf2 PC |
1196 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1197 | "not be accessed in second operand of " | |
ebeb2c24 SZ |
1198 | "conditional expression", expr, type); |
1199 | break; | |
1200 | case ICV_THIRD_OF_COND: | |
5a3c9cf2 PC |
1201 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1202 | "not be accessed in third operand of " | |
ebeb2c24 SZ |
1203 | "conditional expression", expr, type); |
1204 | break; | |
1205 | case ICV_RIGHT_OF_COMMA: | |
5a3c9cf2 PC |
1206 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1207 | "not be accessed in right operand of comma operator", | |
1208 | expr, type); | |
ebeb2c24 SZ |
1209 | break; |
1210 | case ICV_LEFT_OF_COMMA: | |
5a3c9cf2 PC |
1211 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1212 | "not be accessed in left operand of comma operator", | |
1213 | expr, type); | |
ebeb2c24 SZ |
1214 | break; |
1215 | case ICV_STATEMENT: | |
5a3c9cf2 PC |
1216 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1217 | "not be accessed in statement", expr, type); | |
ebeb2c24 SZ |
1218 | break; |
1219 | case ICV_THIRD_IN_FOR: | |
5a3c9cf2 PC |
1220 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1221 | "not be accessed in for increment expression", | |
1222 | expr, type); | |
ebeb2c24 SZ |
1223 | break; |
1224 | default: | |
1225 | gcc_unreachable (); | |
1226 | } | |
1227 | ||
0cbd7506 | 1228 | break; |
02cac427 | 1229 | } |
2bdb0643 | 1230 | |
c08cd4c1 JM |
1231 | case TARGET_EXPR: |
1232 | /* Don't bother with the temporary object returned from a function if | |
1233 | we don't use it and don't need to destroy it. We'll still | |
1234 | allocate space for it in expand_call or declare_return_variable, | |
1235 | but we don't need to track it through all the tree phases. */ | |
5de1a1eb | 1236 | if (TARGET_EXPR_IMPLICIT_P (expr) |
c08cd4c1 JM |
1237 | && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (expr))) |
1238 | { | |
1239 | tree init = TARGET_EXPR_INITIAL (expr); | |
1240 | if (TREE_CODE (init) == AGGR_INIT_EXPR | |
1241 | && !AGGR_INIT_VIA_CTOR_P (init)) | |
1242 | { | |
5039610b | 1243 | tree fn = AGGR_INIT_EXPR_FN (init); |
db3927fb AH |
1244 | expr = build_call_array_loc (input_location, |
1245 | TREE_TYPE (TREE_TYPE (TREE_TYPE (fn))), | |
1246 | fn, | |
1247 | aggr_init_expr_nargs (init), | |
1248 | AGGR_INIT_EXPR_ARGP (init)); | |
c08cd4c1 JM |
1249 | } |
1250 | } | |
1251 | break; | |
1252 | ||
02cac427 NS |
1253 | default:; |
1254 | } | |
ccb05613 | 1255 | expr = resolve_nondeduced_context (expr); |
02cac427 NS |
1256 | { |
1257 | tree probe = expr; | |
c8094d83 | 1258 | |
02cac427 NS |
1259 | if (TREE_CODE (probe) == ADDR_EXPR) |
1260 | probe = TREE_OPERAND (expr, 0); | |
96d6c610 JM |
1261 | if (type_unknown_p (probe)) |
1262 | { | |
1263 | /* [over.over] enumerates the places where we can take the address | |
1264 | of an overloaded function, and this is not one of them. */ | |
5ade1ed2 | 1265 | if (complain & tf_error) |
ebeb2c24 SZ |
1266 | switch (implicit) |
1267 | { | |
1268 | case ICV_CAST: | |
5a3c9cf2 PC |
1269 | error_at (loc, "conversion to void " |
1270 | "cannot resolve address of overloaded function"); | |
ebeb2c24 SZ |
1271 | break; |
1272 | case ICV_SECOND_OF_COND: | |
5a3c9cf2 PC |
1273 | error_at (loc, "second operand of conditional expression " |
1274 | "cannot resolve address of overloaded function"); | |
ebeb2c24 SZ |
1275 | break; |
1276 | case ICV_THIRD_OF_COND: | |
5a3c9cf2 PC |
1277 | error_at (loc, "third operand of conditional expression " |
1278 | "cannot resolve address of overloaded function"); | |
ebeb2c24 SZ |
1279 | break; |
1280 | case ICV_RIGHT_OF_COMMA: | |
5a3c9cf2 PC |
1281 | error_at (loc, "right operand of comma operator " |
1282 | "cannot resolve address of overloaded function"); | |
ebeb2c24 SZ |
1283 | break; |
1284 | case ICV_LEFT_OF_COMMA: | |
5a3c9cf2 PC |
1285 | error_at (loc, "left operand of comma operator " |
1286 | "cannot resolve address of overloaded function"); | |
ebeb2c24 SZ |
1287 | break; |
1288 | case ICV_STATEMENT: | |
5a3c9cf2 PC |
1289 | error_at (loc, "statement " |
1290 | "cannot resolve address of overloaded function"); | |
ebeb2c24 SZ |
1291 | break; |
1292 | case ICV_THIRD_IN_FOR: | |
5a3c9cf2 PC |
1293 | error_at (loc, "for increment expression " |
1294 | "cannot resolve address of overloaded function"); | |
ebeb2c24 SZ |
1295 | break; |
1296 | } | |
5ade1ed2 DG |
1297 | else |
1298 | return error_mark_node; | |
632f2871 | 1299 | expr = void_node; |
96d6c610 | 1300 | } |
ebeb2c24 | 1301 | else if (implicit != ICV_CAST && probe == expr && is_overloaded_fn (probe)) |
05f8c2d5 JM |
1302 | { |
1303 | /* Only warn when there is no &. */ | |
5ade1ed2 | 1304 | if (complain & tf_warning) |
ebeb2c24 SZ |
1305 | switch (implicit) |
1306 | { | |
1307 | case ICV_SECOND_OF_COND: | |
5a3c9cf2 PC |
1308 | warning_at (loc, OPT_Waddress, |
1309 | "second operand of conditional expression " | |
1310 | "is a reference, not call, to function %qE", expr); | |
ebeb2c24 SZ |
1311 | break; |
1312 | case ICV_THIRD_OF_COND: | |
5a3c9cf2 PC |
1313 | warning_at (loc, OPT_Waddress, |
1314 | "third operand of conditional expression " | |
1315 | "is a reference, not call, to function %qE", expr); | |
ebeb2c24 SZ |
1316 | break; |
1317 | case ICV_RIGHT_OF_COMMA: | |
5a3c9cf2 PC |
1318 | warning_at (loc, OPT_Waddress, |
1319 | "right operand of comma operator " | |
1320 | "is a reference, not call, to function %qE", expr); | |
ebeb2c24 SZ |
1321 | break; |
1322 | case ICV_LEFT_OF_COMMA: | |
5a3c9cf2 PC |
1323 | warning_at (loc, OPT_Waddress, |
1324 | "left operand of comma operator " | |
1325 | "is a reference, not call, to function %qE", expr); | |
ebeb2c24 SZ |
1326 | break; |
1327 | case ICV_STATEMENT: | |
5a3c9cf2 PC |
1328 | warning_at (loc, OPT_Waddress, |
1329 | "statement is a reference, not call, to function %qE", | |
1330 | expr); | |
ebeb2c24 SZ |
1331 | break; |
1332 | case ICV_THIRD_IN_FOR: | |
5a3c9cf2 PC |
1333 | warning_at (loc, OPT_Waddress, |
1334 | "for increment expression " | |
1335 | "is a reference, not call, to function %qE", expr); | |
ebeb2c24 SZ |
1336 | break; |
1337 | default: | |
1338 | gcc_unreachable (); | |
1339 | } | |
1340 | ||
05f8c2d5 JM |
1341 | if (TREE_CODE (expr) == COMPONENT_REF) |
1342 | expr = TREE_OPERAND (expr, 0); | |
1343 | } | |
02cac427 | 1344 | } |
c8094d83 | 1345 | |
b72801e2 | 1346 | if (expr != error_mark_node && !VOID_TYPE_P (TREE_TYPE (expr))) |
02cac427 | 1347 | { |
ebeb2c24 | 1348 | if (implicit != ICV_CAST |
55792875 ILT |
1349 | && warn_unused_value |
1350 | && !TREE_NO_WARNING (expr) | |
1351 | && !processing_template_decl) | |
dfb5c523 MM |
1352 | { |
1353 | /* The middle end does not warn about expressions that have | |
1354 | been explicitly cast to void, so we must do so here. */ | |
5ade1ed2 DG |
1355 | if (!TREE_SIDE_EFFECTS (expr)) { |
1356 | if (complain & tf_warning) | |
ebeb2c24 SZ |
1357 | switch (implicit) |
1358 | { | |
1359 | case ICV_SECOND_OF_COND: | |
5a3c9cf2 PC |
1360 | warning_at (loc, OPT_Wunused_value, |
1361 | "second operand of conditional expression " | |
1362 | "has no effect"); | |
ebeb2c24 SZ |
1363 | break; |
1364 | case ICV_THIRD_OF_COND: | |
5a3c9cf2 PC |
1365 | warning_at (loc, OPT_Wunused_value, |
1366 | "third operand of conditional expression " | |
1367 | "has no effect"); | |
ebeb2c24 SZ |
1368 | break; |
1369 | case ICV_RIGHT_OF_COMMA: | |
5a3c9cf2 PC |
1370 | warning_at (loc, OPT_Wunused_value, |
1371 | "right operand of comma operator has no effect"); | |
ebeb2c24 SZ |
1372 | break; |
1373 | case ICV_LEFT_OF_COMMA: | |
5a3c9cf2 PC |
1374 | warning_at (loc, OPT_Wunused_value, |
1375 | "left operand of comma operator has no effect"); | |
ebeb2c24 SZ |
1376 | break; |
1377 | case ICV_STATEMENT: | |
5a3c9cf2 PC |
1378 | warning_at (loc, OPT_Wunused_value, |
1379 | "statement has no effect"); | |
ebeb2c24 SZ |
1380 | break; |
1381 | case ICV_THIRD_IN_FOR: | |
5a3c9cf2 PC |
1382 | warning_at (loc, OPT_Wunused_value, |
1383 | "for increment expression has no effect"); | |
ebeb2c24 SZ |
1384 | break; |
1385 | default: | |
1386 | gcc_unreachable (); | |
1387 | } | |
5ade1ed2 | 1388 | } |
c8094d83 MS |
1389 | else |
1390 | { | |
dfb5c523 MM |
1391 | tree e; |
1392 | enum tree_code code; | |
be93747e | 1393 | enum tree_code_class tclass; |
c8094d83 | 1394 | |
dfb5c523 MM |
1395 | e = expr; |
1396 | /* We might like to warn about (say) "(int) f()", as the | |
1397 | cast has no effect, but the compiler itself will | |
1398 | generate implicit conversions under some | |
cc29fd59 | 1399 | circumstances. (For example a block copy will be |
dfb5c523 MM |
1400 | turned into a call to "__builtin_memcpy", with a |
1401 | conversion of the return value to an appropriate | |
1402 | type.) So, to avoid false positives, we strip | |
d9fa1233 MM |
1403 | conversions. Do not use STRIP_NOPs because it will |
1404 | not strip conversions to "void", as that is not a | |
1405 | mode-preserving conversion. */ | |
1406 | while (TREE_CODE (e) == NOP_EXPR) | |
1407 | e = TREE_OPERAND (e, 0); | |
dfb5c523 MM |
1408 | |
1409 | code = TREE_CODE (e); | |
be93747e KG |
1410 | tclass = TREE_CODE_CLASS (code); |
1411 | if ((tclass == tcc_comparison | |
1412 | || tclass == tcc_unary | |
1413 | || (tclass == tcc_binary | |
dfb5c523 MM |
1414 | && !(code == MODIFY_EXPR |
1415 | || code == INIT_EXPR | |
1416 | || code == PREDECREMENT_EXPR | |
1417 | || code == PREINCREMENT_EXPR | |
1418 | || code == POSTDECREMENT_EXPR | |
5c67ba02 MG |
1419 | || code == POSTINCREMENT_EXPR)) |
1420 | || code == VEC_PERM_EXPR | |
1421 | || code == VEC_COND_EXPR) | |
5ade1ed2 | 1422 | && (complain & tf_warning)) |
5a3c9cf2 | 1423 | warning_at (loc, OPT_Wunused_value, "value computed is not used"); |
dfb5c523 MM |
1424 | } |
1425 | } | |
e895113a | 1426 | expr = build1 (CONVERT_EXPR, void_type_node, expr); |
02cac427 | 1427 | } |
ccbe00a4 | 1428 | if (! TREE_SIDE_EFFECTS (expr)) |
632f2871 | 1429 | expr = void_node; |
02cac427 NS |
1430 | return expr; |
1431 | } | |
1432 | ||
a4443a08 MS |
1433 | /* Create an expression whose value is that of EXPR, |
1434 | converted to type TYPE. The TREE_TYPE of the value | |
1435 | is always TYPE. This function implements all reasonable | |
1436 | conversions; callers should filter out those that are | |
37c46b43 MS |
1437 | not permitted by the language being compiled. |
1438 | ||
1439 | Most of this routine is from build_reinterpret_cast. | |
1440 | ||
3b426391 | 1441 | The back end cannot call cp_convert (what was convert) because |
37c46b43 MS |
1442 | conversions to/from basetypes may involve memory references |
1443 | (vbases) and adding or subtracting small values (multiple | |
1444 | inheritance), but it calls convert from the constant folding code | |
7dfa399d | 1445 | on subtrees of already built trees after it has ripped them apart. |
37c46b43 MS |
1446 | |
1447 | Also, if we ever support range variables, we'll probably also have to | |
1448 | do a little bit more work. */ | |
a4443a08 MS |
1449 | |
1450 | tree | |
b746c5dc | 1451 | convert (tree type, tree expr) |
a4443a08 | 1452 | { |
37c46b43 MS |
1453 | tree intype; |
1454 | ||
1455 | if (type == error_mark_node || expr == error_mark_node) | |
1456 | return error_mark_node; | |
1457 | ||
37c46b43 MS |
1458 | intype = TREE_TYPE (expr); |
1459 | ||
6633d636 | 1460 | if (POINTER_TYPE_P (type) && POINTER_TYPE_P (intype)) |
8a784e4a | 1461 | return fold_if_not_in_template (build_nop (type, expr)); |
37c46b43 MS |
1462 | |
1463 | return ocp_convert (type, expr, CONV_OLD_CONVERT, | |
4b978f96 PC |
1464 | LOOKUP_NORMAL|LOOKUP_NO_CONVERSION, |
1465 | tf_warning_or_error); | |
a4443a08 MS |
1466 | } |
1467 | ||
37c46b43 | 1468 | /* Like cp_convert, except permit conversions to take place which |
8d08fdba MS |
1469 | are not normally allowed due to access restrictions |
1470 | (such as conversion from sub-type to private super-type). */ | |
e92cc029 | 1471 | |
8d08fdba | 1472 | tree |
4b978f96 | 1473 | convert_force (tree type, tree expr, int convtype, tsubst_flags_t complain) |
8d08fdba | 1474 | { |
926ce8bd KH |
1475 | tree e = expr; |
1476 | enum tree_code code = TREE_CODE (type); | |
8d08fdba MS |
1477 | |
1478 | if (code == REFERENCE_TYPE) | |
c8094d83 | 1479 | return (fold_if_not_in_template |
4b978f96 PC |
1480 | (convert_to_reference (type, e, CONV_C_CAST, 0, |
1481 | NULL_TREE, complain))); | |
8d08fdba MS |
1482 | |
1483 | if (code == POINTER_TYPE) | |
4b978f96 PC |
1484 | return fold_if_not_in_template (convert_to_pointer_force (type, e, |
1485 | complain)); | |
8d08fdba | 1486 | |
51c184be | 1487 | /* From typeck.c convert_for_assignment */ |
50e10fa8 | 1488 | if (((TYPE_PTR_P (TREE_TYPE (e)) && TREE_CODE (e) == ADDR_EXPR |
8d08fdba | 1489 | && TREE_CODE (TREE_TYPE (TREE_TYPE (e))) == METHOD_TYPE) |
51c184be MS |
1490 | || integer_zerop (e) |
1491 | || TYPE_PTRMEMFUNC_P (TREE_TYPE (e))) | |
8d08fdba | 1492 | && TYPE_PTRMEMFUNC_P (type)) |
08e17d9d MM |
1493 | /* compatible pointer to member functions. */ |
1494 | return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), e, 1, | |
4b978f96 | 1495 | /*c_cast_p=*/1, complain); |
6060a796 | 1496 | |
4b978f96 | 1497 | return ocp_convert (type, e, CONV_C_CAST|convtype, LOOKUP_NORMAL, complain); |
8d08fdba MS |
1498 | } |
1499 | ||
8d08fdba MS |
1500 | /* Convert an aggregate EXPR to type XTYPE. If a conversion |
1501 | exists, return the attempted conversion. This may | |
1502 | return ERROR_MARK_NODE if the conversion is not | |
1503 | allowed (references private members, etc). | |
1504 | If no conversion exists, NULL_TREE is returned. | |
1505 | ||
f30432d7 MS |
1506 | FIXME: Ambiguity checking is wrong. Should choose one by the implicit |
1507 | object parameter, or by the second standard conversion sequence if | |
1508 | that doesn't do it. This will probably wait for an overloading rewrite. | |
1509 | (jason 8/9/95) */ | |
8d08fdba | 1510 | |
ae00383b | 1511 | static tree |
7993382e | 1512 | build_type_conversion (tree xtype, tree expr) |
8d08fdba MS |
1513 | { |
1514 | /* C++: check to see if we can convert this aggregate type | |
e1cd6e56 | 1515 | into the required type. */ |
b40e334f PC |
1516 | return build_user_type_conversion (xtype, expr, LOOKUP_NORMAL, |
1517 | tf_warning_or_error); | |
8d08fdba MS |
1518 | } |
1519 | ||
b7484fbe MS |
1520 | /* Convert the given EXPR to one of a group of types suitable for use in an |
1521 | expression. DESIRES is a combination of various WANT_* flags (q.v.) | |
b746c5dc | 1522 | which indicates which types are suitable. If COMPLAIN is true, complain |
b7484fbe | 1523 | about ambiguity; otherwise, the caller will deal with it. */ |
8d08fdba | 1524 | |
b7484fbe | 1525 | tree |
b746c5dc | 1526 | build_expr_type_conversion (int desires, tree expr, bool complain) |
8d08fdba | 1527 | { |
b7484fbe | 1528 | tree basetype = TREE_TYPE (expr); |
b370501f | 1529 | tree conv = NULL_TREE; |
02020185 | 1530 | tree winner = NULL_TREE; |
8d08fdba | 1531 | |
c8094d83 MS |
1532 | if (expr == null_node |
1533 | && (desires & WANT_INT) | |
03d0f4af | 1534 | && !(desires & WANT_NULL)) |
70dc395a DS |
1535 | { |
1536 | source_location loc = | |
1537 | expansion_point_location_if_in_system_header (input_location); | |
1538 | ||
1539 | warning_at (loc, OPT_Wconversion_null, | |
1540 | "converting NULL to non-pointer type"); | |
1541 | } | |
c8094d83 | 1542 | |
07c88314 MM |
1543 | if (basetype == error_mark_node) |
1544 | return error_mark_node; | |
1545 | ||
9e1e64ec | 1546 | if (! MAYBE_CLASS_TYPE_P (basetype)) |
02020185 JM |
1547 | switch (TREE_CODE (basetype)) |
1548 | { | |
1549 | case INTEGER_TYPE: | |
03d0f4af | 1550 | if ((desires & WANT_NULL) && null_ptr_cst_p (expr)) |
02020185 JM |
1551 | return expr; |
1552 | /* else fall through... */ | |
1553 | ||
1554 | case BOOLEAN_TYPE: | |
1555 | return (desires & WANT_INT) ? expr : NULL_TREE; | |
1556 | case ENUMERAL_TYPE: | |
1557 | return (desires & WANT_ENUM) ? expr : NULL_TREE; | |
1558 | case REAL_TYPE: | |
1559 | return (desires & WANT_FLOAT) ? expr : NULL_TREE; | |
1560 | case POINTER_TYPE: | |
1561 | return (desires & WANT_POINTER) ? expr : NULL_TREE; | |
c8094d83 | 1562 | |
02020185 JM |
1563 | case FUNCTION_TYPE: |
1564 | case ARRAY_TYPE: | |
89fcabaf PC |
1565 | return (desires & WANT_POINTER) ? decay_conversion (expr, |
1566 | tf_warning_or_error) | |
0cbd7506 | 1567 | : NULL_TREE; |
4576ceaf | 1568 | |
1ff6b2c8 | 1569 | case COMPLEX_TYPE: |
4576ceaf | 1570 | case VECTOR_TYPE: |
1ff6b2c8 | 1571 | if ((desires & WANT_VECTOR_OR_COMPLEX) == 0) |
4576ceaf JJ |
1572 | return NULL_TREE; |
1573 | switch (TREE_CODE (TREE_TYPE (basetype))) | |
1574 | { | |
1575 | case INTEGER_TYPE: | |
1576 | case BOOLEAN_TYPE: | |
1577 | return (desires & WANT_INT) ? expr : NULL_TREE; | |
1578 | case ENUMERAL_TYPE: | |
1579 | return (desires & WANT_ENUM) ? expr : NULL_TREE; | |
1580 | case REAL_TYPE: | |
1581 | return (desires & WANT_FLOAT) ? expr : NULL_TREE; | |
1582 | default: | |
1583 | return NULL_TREE; | |
1584 | } | |
1585 | ||
02020185 JM |
1586 | default: |
1587 | return NULL_TREE; | |
1588 | } | |
1589 | ||
1590 | /* The code for conversions from class type is currently only used for | |
1591 | delete expressions. Other expressions are handled by build_new_op. */ | |
309714d4 | 1592 | if (!complete_type_or_maybe_complain (basetype, expr, complain)) |
29f4ceab GB |
1593 | return error_mark_node; |
1594 | if (!TYPE_HAS_CONVERSION (basetype)) | |
02020185 JM |
1595 | return NULL_TREE; |
1596 | ||
9c7d5cae | 1597 | for (conv = lookup_conversions (basetype); conv; conv = TREE_CHAIN (conv)) |
02020185 JM |
1598 | { |
1599 | int win = 0; | |
1600 | tree candidate; | |
1601 | tree cand = TREE_VALUE (conv); | |
a5cf630e | 1602 | cand = OVL_CURRENT (cand); |
02020185 JM |
1603 | |
1604 | if (winner && winner == cand) | |
1605 | continue; | |
1606 | ||
e57d93c6 JM |
1607 | if (DECL_NONCONVERTING_P (cand)) |
1608 | continue; | |
1609 | ||
ee76b931 | 1610 | candidate = non_reference (TREE_TYPE (TREE_TYPE (cand))); |
02020185 JM |
1611 | |
1612 | switch (TREE_CODE (candidate)) | |
1613 | { | |
1614 | case BOOLEAN_TYPE: | |
1615 | case INTEGER_TYPE: | |
1616 | win = (desires & WANT_INT); break; | |
1617 | case ENUMERAL_TYPE: | |
1618 | win = (desires & WANT_ENUM); break; | |
1619 | case REAL_TYPE: | |
1620 | win = (desires & WANT_FLOAT); break; | |
1621 | case POINTER_TYPE: | |
1622 | win = (desires & WANT_POINTER); break; | |
1623 | ||
1ff6b2c8 | 1624 | case COMPLEX_TYPE: |
4576ceaf | 1625 | case VECTOR_TYPE: |
1ff6b2c8 | 1626 | if ((desires & WANT_VECTOR_OR_COMPLEX) == 0) |
4576ceaf JJ |
1627 | break; |
1628 | switch (TREE_CODE (TREE_TYPE (candidate))) | |
1629 | { | |
1630 | case BOOLEAN_TYPE: | |
1631 | case INTEGER_TYPE: | |
1632 | win = (desires & WANT_INT); break; | |
1633 | case ENUMERAL_TYPE: | |
1634 | win = (desires & WANT_ENUM); break; | |
1635 | case REAL_TYPE: | |
1636 | win = (desires & WANT_FLOAT); break; | |
1637 | default: | |
1638 | break; | |
1639 | } | |
1640 | break; | |
1641 | ||
02020185 | 1642 | default: |
c5918c21 JM |
1643 | /* A wildcard could be instantiated to match any desired |
1644 | type, but we can't deduce the template argument. */ | |
1645 | if (WILDCARD_TYPE_P (candidate)) | |
1646 | win = true; | |
02020185 JM |
1647 | break; |
1648 | } | |
1649 | ||
1650 | if (win) | |
1651 | { | |
c5918c21 JM |
1652 | if (TREE_CODE (cand) == TEMPLATE_DECL) |
1653 | { | |
1654 | if (complain) | |
1655 | error ("default type conversion can't deduce template" | |
1656 | " argument for %qD", cand); | |
1657 | return error_mark_node; | |
1658 | } | |
1659 | ||
02020185 JM |
1660 | if (winner) |
1661 | { | |
ca45eca1 JM |
1662 | tree winner_type |
1663 | = non_reference (TREE_TYPE (TREE_TYPE (winner))); | |
1664 | ||
1665 | if (!same_type_ignoring_top_level_qualifiers_p (winner_type, | |
1666 | candidate)) | |
02020185 | 1667 | { |
ca45eca1 JM |
1668 | if (complain) |
1669 | { | |
1670 | error ("ambiguous default type conversion from %qT", | |
1671 | basetype); | |
2d45625f PC |
1672 | inform (input_location, |
1673 | " candidate conversions include %qD and %qD", | |
1674 | winner, cand); | |
ca45eca1 JM |
1675 | } |
1676 | return error_mark_node; | |
02020185 | 1677 | } |
02020185 | 1678 | } |
ca45eca1 JM |
1679 | |
1680 | winner = cand; | |
02020185 JM |
1681 | } |
1682 | } | |
b7484fbe | 1683 | |
02020185 JM |
1684 | if (winner) |
1685 | { | |
ee76b931 | 1686 | tree type = non_reference (TREE_TYPE (TREE_TYPE (winner))); |
b40e334f PC |
1687 | return build_user_type_conversion (type, expr, LOOKUP_NORMAL, |
1688 | tf_warning_or_error); | |
8d08fdba | 1689 | } |
b7484fbe | 1690 | |
3c215895 | 1691 | return NULL_TREE; |
8d08fdba | 1692 | } |
39211cd5 | 1693 | |
e92cc029 MS |
1694 | /* Implements integral promotion (4.1) and float->double promotion. */ |
1695 | ||
39211cd5 | 1696 | tree |
b746c5dc | 1697 | type_promotes_to (tree type) |
39211cd5 | 1698 | { |
40449a90 SL |
1699 | tree promoted_type; |
1700 | ||
f30432d7 MS |
1701 | if (type == error_mark_node) |
1702 | return error_mark_node; | |
1703 | ||
39211cd5 | 1704 | type = TYPE_MAIN_VARIANT (type); |
2986ae00 | 1705 | |
40449a90 SL |
1706 | /* Check for promotions of target-defined types first. */ |
1707 | promoted_type = targetm.promoted_type (type); | |
1708 | if (promoted_type) | |
1709 | return promoted_type; | |
1710 | ||
2986ae00 MS |
1711 | /* bool always promotes to int (not unsigned), even if it's the same |
1712 | size. */ | |
66be89f0 | 1713 | if (TREE_CODE (type) == BOOLEAN_TYPE) |
2986ae00 MS |
1714 | type = integer_type_node; |
1715 | ||
1716 | /* Normally convert enums to int, but convert wide enums to something | |
62984918 JM |
1717 | wider. Scoped enums don't promote, but pretend they do for backward |
1718 | ABI bug compatibility wrt varargs. */ | |
2986ae00 | 1719 | else if (TREE_CODE (type) == ENUMERAL_TYPE |
b6baa67d KVH |
1720 | || type == char16_type_node |
1721 | || type == char32_type_node | |
2986ae00 | 1722 | || type == wchar_type_node) |
cf2ac46f JM |
1723 | { |
1724 | int precision = MAX (TYPE_PRECISION (type), | |
1725 | TYPE_PRECISION (integer_type_node)); | |
b0c48229 | 1726 | tree totype = c_common_type_for_size (precision, 0); |
62984918 JM |
1727 | tree prom = type; |
1728 | if (TREE_CODE (prom) == ENUMERAL_TYPE) | |
1729 | prom = ENUM_UNDERLYING_TYPE (prom); | |
1730 | if (TYPE_UNSIGNED (prom) | |
1731 | && ! int_fits_type_p (TYPE_MAX_VALUE (prom), totype)) | |
1732 | prom = c_common_type_for_size (precision, 1); | |
1733 | else | |
1734 | prom = totype; | |
967444bb | 1735 | if (SCOPED_ENUM_P (type)) |
62984918 JM |
1736 | { |
1737 | if (abi_version_crosses (6) | |
1738 | && TYPE_MODE (prom) != TYPE_MODE (type)) | |
1739 | warning (OPT_Wabi, "scoped enum %qT passed through ... as " | |
1740 | "%qT before -fabi-version=6, %qT after", | |
1741 | type, prom, ENUM_UNDERLYING_TYPE (type)); | |
1742 | if (!abi_version_at_least (6)) | |
1743 | type = prom; | |
1744 | } | |
cf2ac46f | 1745 | else |
62984918 | 1746 | type = prom; |
cf2ac46f | 1747 | } |
d72040f5 | 1748 | else if (c_promoting_integer_type_p (type)) |
39211cd5 | 1749 | { |
3d4683cb | 1750 | /* Retain unsignedness if really not getting bigger. */ |
8df83eae | 1751 | if (TYPE_UNSIGNED (type) |
3d4683cb | 1752 | && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)) |
39211cd5 MS |
1753 | type = unsigned_type_node; |
1754 | else | |
1755 | type = integer_type_node; | |
1756 | } | |
1757 | else if (type == float_type_node) | |
1758 | type = double_type_node; | |
c8094d83 | 1759 | |
0a72704b | 1760 | return type; |
39211cd5 | 1761 | } |
75650646 | 1762 | |
75650646 MM |
1763 | /* The routines below this point are carefully written to conform to |
1764 | the standard. They use the same terminology, and follow the rules | |
1765 | closely. Although they are used only in pt.c at the moment, they | |
1766 | should presumably be used everywhere in the future. */ | |
1767 | ||
e1467ff2 MM |
1768 | /* Attempt to perform qualification conversions on EXPR to convert it |
1769 | to TYPE. Return the resulting expression, or error_mark_node if | |
1770 | the conversion was impossible. */ | |
1771 | ||
c8094d83 | 1772 | tree |
b746c5dc | 1773 | perform_qualification_conversions (tree type, tree expr) |
75650646 | 1774 | { |
a5ac359a MM |
1775 | tree expr_type; |
1776 | ||
1777 | expr_type = TREE_TYPE (expr); | |
1778 | ||
6f25cb35 MM |
1779 | if (same_type_p (type, expr_type)) |
1780 | return expr; | |
1781 | else if (TYPE_PTR_P (type) && TYPE_PTR_P (expr_type) | |
1782 | && comp_ptr_ttypes (TREE_TYPE (type), TREE_TYPE (expr_type))) | |
a5ac359a | 1783 | return build_nop (type, expr); |
66b1156a | 1784 | else if (TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (expr_type) |
a5ac359a MM |
1785 | && same_type_p (TYPE_PTRMEM_CLASS_TYPE (type), |
1786 | TYPE_PTRMEM_CLASS_TYPE (expr_type)) | |
1787 | && comp_ptr_ttypes (TYPE_PTRMEM_POINTED_TO_TYPE (type), | |
1788 | TYPE_PTRMEM_POINTED_TO_TYPE (expr_type))) | |
1789 | return build_nop (type, expr); | |
e1467ff2 MM |
1790 | else |
1791 | return error_mark_node; | |
75650646 | 1792 | } |
b8fd7909 JM |
1793 | |
1794 | /* True iff T is a transaction-safe function type. */ | |
1795 | ||
1796 | bool | |
1797 | tx_safe_fn_type_p (tree t) | |
1798 | { | |
1799 | if (TREE_CODE (t) != FUNCTION_TYPE | |
1800 | && TREE_CODE (t) != METHOD_TYPE) | |
1801 | return false; | |
1802 | return !!lookup_attribute ("transaction_safe", TYPE_ATTRIBUTES (t)); | |
1803 | } | |
1804 | ||
1805 | /* Return the transaction-unsafe variant of transaction-safe function type | |
1806 | T. */ | |
1807 | ||
1808 | tree | |
1809 | tx_unsafe_fn_variant (tree t) | |
1810 | { | |
1811 | gcc_assert (tx_safe_fn_type_p (t)); | |
1812 | tree attrs = remove_attribute ("transaction_safe", | |
1813 | TYPE_ATTRIBUTES (t)); | |
1814 | return cp_build_type_attribute_variant (t, attrs); | |
1815 | } | |
1816 | ||
1817 | /* Return true iff FROM can convert to TO by a transaction-safety | |
1818 | conversion. */ | |
1819 | ||
1820 | bool | |
1821 | can_convert_tx_safety (tree to, tree from) | |
1822 | { | |
1823 | return (flag_tm && tx_safe_fn_type_p (from) | |
1824 | && same_type_p (to, tx_unsafe_fn_variant (from))); | |
1825 | } |