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471086d6 | 1 | /* Language-level data type conversion for GNU C++. |
8e8f6434 | 2 | Copyright (C) 1987-2018 Free Software Foundation, Inc. |
471086d6 | 3 | Hacked by Michael Tiemann (tiemann@cygnus.com) |
4 | ||
6f0d25a6 | 5 | This file is part of GCC. |
471086d6 | 6 | |
6f0d25a6 | 7 | GCC is free software; you can redistribute it and/or modify |
471086d6 | 8 | it under the terms of the GNU General Public License as published by |
aa139c3f | 9 | the Free Software Foundation; either version 3, or (at your option) |
471086d6 | 10 | any later version. |
11 | ||
6f0d25a6 | 12 | GCC is distributed in the hope that it will be useful, |
471086d6 | 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 | |
aa139c3f | 18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ | |
471086d6 | 20 | |
21 | ||
af86cc06 | 22 | /* This file contains the functions for converting C++ expressions |
471086d6 | 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" | |
b3ef7553 | 28 | #include "system.h" |
805e22b2 | 29 | #include "coretypes.h" |
4cba6f60 | 30 | #include "target.h" |
4cba6f60 | 31 | #include "cp-tree.h" |
9ed99284 | 32 | #include "stor-layout.h" |
471086d6 | 33 | #include "flags.h" |
ca82e026 | 34 | #include "intl.h" |
471086d6 | 35 | #include "convert.h" |
30a86690 | 36 | #include "stringpool.h" |
37 | #include "attribs.h" | |
96624a9e | 38 | |
c4698a21 | 39 | static tree convert_to_pointer_force (tree, tree, tsubst_flags_t); |
ef9571e5 | 40 | static tree build_type_conversion (tree, tree); |
c4698a21 | 41 | static tree build_up_reference (tree, tree, int, tree, tsubst_flags_t); |
19b271a9 | 42 | static void diagnose_ref_binding (location_t, tree, tree, tree); |
71ccdfff | 43 | |
471086d6 | 44 | /* Change of width--truncation and extension of integers or reals-- |
45 | is represented with NOP_EXPR. Proper functioning of many things | |
46 | assumes that no other conversions can be NOP_EXPRs. | |
47 | ||
48 | Conversion between integer and pointer is represented with CONVERT_EXPR. | |
49 | Converting integer to real uses FLOAT_EXPR | |
50 | and real to integer uses FIX_TRUNC_EXPR. | |
51 | ||
52 | Here is a list of all the functions that assume that widening and | |
53 | narrowing is always done with a NOP_EXPR: | |
b981525c | 54 | In convert.c, convert_to_integer[_maybe_fold]. |
471086d6 | 55 | In c-typeck.c, build_binary_op_nodefault (boolean ops), |
653e5405 | 56 | and c_common_truthvalue_conversion. |
471086d6 | 57 | In expr.c: expand_expr, for operands of a MULT_EXPR. |
58 | In fold-const.c: fold. | |
59 | In tree.c: get_narrower and get_unwidened. | |
60 | ||
61 | C++: in multiple-inheritance, converting between pointers may involve | |
62 | adjusting them by a delta stored within the class definition. */ | |
63 | \f | |
64 | /* Subroutines of `convert'. */ | |
65 | ||
471086d6 | 66 | /* if converting pointer to pointer |
67 | if dealing with classes, check for derived->base or vice versa | |
68 | else if dealing with method pointers, delegate | |
69 | else convert blindly | |
70 | else if converting class, pass off to build_type_conversion | |
e5ead12a | 71 | else try C-style pointer conversion. */ |
96624a9e | 72 | |
471086d6 | 73 | static tree |
b981525c | 74 | cp_convert_to_pointer (tree type, tree expr, bool dofold, |
75 | tsubst_flags_t complain) | |
471086d6 | 76 | { |
cd16867a | 77 | tree intype = TREE_TYPE (expr); |
78 | enum tree_code form; | |
f82eeb87 | 79 | tree rval; |
3df42822 | 80 | location_t loc = EXPR_LOC_OR_LOC (expr, input_location); |
61f69bc9 | 81 | |
8bf328bf | 82 | if (intype == error_mark_node) |
83 | return error_mark_node; | |
74002e1d | 84 | |
95397ff9 | 85 | if (MAYBE_CLASS_TYPE_P (intype)) |
96624a9e | 86 | { |
96624a9e | 87 | intype = complete_type (intype); |
4b72716d | 88 | if (!COMPLETE_TYPE_P (intype)) |
96624a9e | 89 | { |
c4698a21 | 90 | if (complain & tf_error) |
4d1eda3a | 91 | error_at (loc, "can%'t convert from incomplete type %qH to %qI", |
c4698a21 | 92 | intype, type); |
96624a9e | 93 | return error_mark_node; |
94 | } | |
95 | ||
8999978b | 96 | rval = build_type_conversion (type, expr); |
96624a9e | 97 | if (rval) |
98 | { | |
c4698a21 | 99 | if ((complain & tf_error) |
100 | && rval == error_mark_node) | |
4d1eda3a | 101 | error_at (loc, "conversion of %qE from %qH to %qI is ambiguous", |
61f69bc9 | 102 | expr, intype, type); |
96624a9e | 103 | return rval; |
104 | } | |
105 | } | |
106 | ||
860740a7 | 107 | /* Handle anachronistic conversions from (::*)() to cv void* or (*)(). */ |
c21c015b | 108 | if (TYPE_PTR_P (type) |
38281c46 | 109 | && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE |
e3cfe3ce | 110 | || VOID_TYPE_P (TREE_TYPE (type)))) |
38281c46 | 111 | { |
6ab399e8 | 112 | if (TYPE_PTRMEMFUNC_P (intype) |
113 | || TREE_CODE (intype) == METHOD_TYPE) | |
c4698a21 | 114 | return convert_member_func_to_ptr (type, expr, complain); |
c21c015b | 115 | if (TYPE_PTR_P (TREE_TYPE (expr))) |
a63bc44c | 116 | return build_nop (type, expr); |
38281c46 | 117 | intype = TREE_TYPE (expr); |
118 | } | |
119 | ||
311e42bc | 120 | if (expr == error_mark_node) |
121 | return error_mark_node; | |
122 | ||
74002e1d | 123 | form = TREE_CODE (intype); |
124 | ||
2b77484d | 125 | if (POINTER_TYPE_P (intype)) |
471086d6 | 126 | { |
127 | intype = TYPE_MAIN_VARIANT (intype); | |
128 | ||
129 | if (TYPE_MAIN_VARIANT (type) != intype | |
c21c015b | 130 | && TYPE_PTR_P (type) |
471086d6 | 131 | && TREE_CODE (TREE_TYPE (type)) == RECORD_TYPE |
95397ff9 | 132 | && MAYBE_CLASS_TYPE_P (TREE_TYPE (type)) |
133 | && MAYBE_CLASS_TYPE_P (TREE_TYPE (intype)) | |
4a2680fc | 134 | && TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE) |
471086d6 | 135 | { |
136 | enum tree_code code = PLUS_EXPR; | |
4a2680fc | 137 | tree binfo; |
8999978b | 138 | tree intype_class; |
139 | tree type_class; | |
140 | bool same_p; | |
4a2680fc | 141 | |
8999978b | 142 | intype_class = TREE_TYPE (intype); |
143 | type_class = TREE_TYPE (type); | |
144 | ||
9031d10b | 145 | same_p = same_type_p (TYPE_MAIN_VARIANT (intype_class), |
8999978b | 146 | TYPE_MAIN_VARIANT (type_class)); |
147 | binfo = NULL_TREE; | |
c0af329c | 148 | /* Try derived to base conversion. */ |
8999978b | 149 | if (!same_p) |
ae260dcc | 150 | binfo = lookup_base (intype_class, type_class, ba_check, |
151 | NULL, complain); | |
8999978b | 152 | if (!same_p && !binfo) |
471086d6 | 153 | { |
c0af329c | 154 | /* Try base to derived conversion. */ |
ae260dcc | 155 | binfo = lookup_base (type_class, intype_class, ba_check, |
156 | NULL, complain); | |
471086d6 | 157 | code = MINUS_EXPR; |
158 | } | |
4a2680fc | 159 | if (binfo == error_mark_node) |
160 | return error_mark_node; | |
8999978b | 161 | if (binfo || same_p) |
471086d6 | 162 | { |
8999978b | 163 | if (binfo) |
c4698a21 | 164 | expr = build_base_path (code, expr, binfo, 0, complain); |
c0af329c | 165 | /* Add any qualifier conversions. */ |
8999978b | 166 | return build_nop (type, expr); |
471086d6 | 167 | } |
168 | } | |
471086d6 | 169 | |
1bc16cab | 170 | if (TYPE_PTRMEMFUNC_P (type)) |
bea7d742 | 171 | { |
c4698a21 | 172 | if (complain & tf_error) |
4d1eda3a | 173 | error_at (loc, "cannot convert %qE from type %qH to type %qI", |
c4698a21 | 174 | expr, intype, type); |
1bc16cab | 175 | return error_mark_node; |
176 | } | |
a17aefa2 | 177 | |
1bc16cab | 178 | return build_nop (type, expr); |
179 | } | |
05765a91 | 180 | else if ((TYPE_PTRDATAMEM_P (type) && TYPE_PTRDATAMEM_P (intype)) |
e5ead12a | 181 | || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype))) |
182 | return convert_ptrmem (type, expr, /*allow_inverse_p=*/false, | |
c4698a21 | 183 | /*c_cast_p=*/false, complain); |
2b77484d | 184 | else if (TYPE_PTRMEMFUNC_P (intype)) |
185 | { | |
a63bc44c | 186 | if (!warn_pmf2ptr) |
187 | { | |
188 | if (TREE_CODE (expr) == PTRMEM_CST) | |
c4698a21 | 189 | return cp_convert_to_pointer (type, PTRMEM_CST_MEMBER (expr), |
b981525c | 190 | dofold, complain); |
a63bc44c | 191 | else if (TREE_CODE (expr) == OFFSET_REF) |
192 | { | |
193 | tree object = TREE_OPERAND (expr, 0); | |
194 | return get_member_function_from_ptrfunc (&object, | |
4405c1ad | 195 | TREE_OPERAND (expr, 1), |
c4698a21 | 196 | complain); |
a63bc44c | 197 | } |
198 | } | |
d3f0af4b | 199 | if (complain & tf_error) |
4d1eda3a | 200 | error_at (loc, "cannot convert %qE from type %qH to type %qI", |
d3f0af4b | 201 | expr, intype, type); |
2b77484d | 202 | return error_mark_node; |
203 | } | |
471086d6 | 204 | |
ef434176 | 205 | if (null_ptr_cst_p (expr)) |
471086d6 | 206 | { |
2b77484d | 207 | if (TYPE_PTRMEMFUNC_P (type)) |
cb02169c | 208 | return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr, 0, |
c4698a21 | 209 | /*c_cast_p=*/false, complain); |
ad63a0fc | 210 | |
106c3d67 | 211 | if (complain & tf_warning) |
212 | maybe_warn_zero_as_null_pointer_constant (expr, loc); | |
213 | ||
7ba2f86f | 214 | /* A NULL pointer-to-data-member is represented by -1, not by |
215 | zero. */ | |
216 | tree val = (TYPE_PTRDATAMEM_P (type) | |
217 | ? build_int_cst_type (type, -1) | |
218 | : build_int_cst (type, 0)); | |
219 | ||
220 | return (TREE_SIDE_EFFECTS (expr) | |
221 | ? build2 (COMPOUND_EXPR, type, expr, val) : val); | |
471086d6 | 222 | } |
05765a91 | 223 | else if (TYPE_PTRMEM_P (type) && INTEGRAL_CODE_P (form)) |
de1f960a | 224 | { |
c4698a21 | 225 | if (complain & tf_error) |
4d1eda3a | 226 | error_at (loc, "invalid conversion from %qH to %qI", intype, type); |
de1f960a | 227 | return error_mark_node; |
228 | } | |
471086d6 | 229 | |
bb0726a1 | 230 | if (INTEGRAL_CODE_P (form)) |
471086d6 | 231 | { |
c5aa1e92 | 232 | if (TYPE_PRECISION (intype) == POINTER_SIZE) |
471086d6 | 233 | return build1 (CONVERT_EXPR, type, expr); |
c4698a21 | 234 | expr = cp_convert (c_common_type_for_size (POINTER_SIZE, 0), expr, |
235 | complain); | |
092b1d6f | 236 | /* Modes may be different but sizes should be the same. There |
237 | is supposed to be some integral type that is the same width | |
238 | as a pointer. */ | |
03b7a719 | 239 | gcc_assert (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (expr))) |
240 | == GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (type))); | |
9031d10b | 241 | |
81cc7d9c | 242 | /* FIXME needed because convert_to_pointer_maybe_fold still folds |
243 | conversion of constants. */ | |
244 | if (!dofold) | |
245 | return build1 (CONVERT_EXPR, type, expr); | |
246 | ||
b981525c | 247 | return convert_to_pointer_maybe_fold (type, expr, dofold); |
471086d6 | 248 | } |
249 | ||
cc4d0855 | 250 | if (type_unknown_p (expr)) |
c4698a21 | 251 | return instantiate_type (type, expr, complain); |
cc4d0855 | 252 | |
c4698a21 | 253 | if (complain & tf_error) |
4d1eda3a | 254 | error_at (loc, "cannot convert %qE from type %qH to type %qI", |
c4698a21 | 255 | expr, intype, type); |
471086d6 | 256 | return error_mark_node; |
257 | } | |
258 | ||
259 | /* Like convert, except permit conversions to take place which | |
260 | are not normally allowed due to access restrictions | |
261 | (such as conversion from sub-type to private super-type). */ | |
96624a9e | 262 | |
471086d6 | 263 | static tree |
c4698a21 | 264 | convert_to_pointer_force (tree type, tree expr, tsubst_flags_t complain) |
471086d6 | 265 | { |
cd16867a | 266 | tree intype = TREE_TYPE (expr); |
267 | enum tree_code form = TREE_CODE (intype); | |
9031d10b | 268 | |
471086d6 | 269 | if (form == POINTER_TYPE) |
270 | { | |
271 | intype = TYPE_MAIN_VARIANT (intype); | |
272 | ||
273 | if (TYPE_MAIN_VARIANT (type) != intype | |
274 | && TREE_CODE (TREE_TYPE (type)) == RECORD_TYPE | |
95397ff9 | 275 | && MAYBE_CLASS_TYPE_P (TREE_TYPE (type)) |
276 | && MAYBE_CLASS_TYPE_P (TREE_TYPE (intype)) | |
471086d6 | 277 | && TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE) |
278 | { | |
279 | enum tree_code code = PLUS_EXPR; | |
4a2680fc | 280 | tree binfo; |
281 | ||
282 | binfo = lookup_base (TREE_TYPE (intype), TREE_TYPE (type), | |
ae260dcc | 283 | ba_unique, NULL, complain); |
4a2680fc | 284 | if (!binfo) |
471086d6 | 285 | { |
4a2680fc | 286 | binfo = lookup_base (TREE_TYPE (type), TREE_TYPE (intype), |
ae260dcc | 287 | ba_unique, NULL, complain); |
4a2680fc | 288 | code = MINUS_EXPR; |
471086d6 | 289 | } |
4a2680fc | 290 | if (binfo == error_mark_node) |
291 | return error_mark_node; | |
292 | if (binfo) | |
471086d6 | 293 | { |
c4698a21 | 294 | expr = build_base_path (code, expr, binfo, 0, complain); |
653e5405 | 295 | if (expr == error_mark_node) |
296 | return error_mark_node; | |
c0af329c | 297 | /* Add any qualifier conversions. */ |
4a2680fc | 298 | if (!same_type_p (TREE_TYPE (TREE_TYPE (expr)), |
299 | TREE_TYPE (type))) | |
8999978b | 300 | expr = build_nop (type, expr); |
4a2680fc | 301 | return expr; |
471086d6 | 302 | } |
471086d6 | 303 | } |
471086d6 | 304 | } |
305 | ||
b981525c | 306 | return cp_convert_to_pointer (type, expr, /*fold*/false, complain); |
471086d6 | 307 | } |
308 | ||
309 | /* We are passing something to a function which requires a reference. | |
310 | The type we are interested in is in TYPE. The initial | |
311 | value we have to begin with is in ARG. | |
312 | ||
313 | FLAGS controls how we manage access checking. | |
ca106ab1 | 314 | DIRECT_BIND in FLAGS controls how any temporaries are generated. |
315 | If DIRECT_BIND is set, DECL is the reference we're binding to. */ | |
96624a9e | 316 | |
471086d6 | 317 | static tree |
c4698a21 | 318 | build_up_reference (tree type, tree arg, int flags, tree decl, |
319 | tsubst_flags_t complain) | |
471086d6 | 320 | { |
c76251c1 | 321 | tree rval; |
0543e7a9 | 322 | tree argtype = TREE_TYPE (arg); |
471086d6 | 323 | tree target_type = TREE_TYPE (type); |
471086d6 | 324 | |
b4df430b | 325 | gcc_assert (TREE_CODE (type) == REFERENCE_TYPE); |
471086d6 | 326 | |
18bede74 | 327 | if ((flags & DIRECT_BIND) && ! lvalue_p (arg)) |
471086d6 | 328 | { |
ca106ab1 | 329 | /* Create a new temporary variable. We can't just use a TARGET_EXPR |
330 | here because it needs to live as long as DECL. */ | |
c76251c1 | 331 | tree targ = arg; |
ca106ab1 | 332 | |
5ab1aaca | 333 | arg = make_temporary_var_for_ref_to_temp (decl, target_type); |
c23ebfdd | 334 | |
335 | /* Process the initializer for the declaration. */ | |
38281c46 | 336 | DECL_INITIAL (arg) = targ; |
d91303a6 | 337 | cp_finish_decl (arg, targ, /*init_const_expr_p=*/false, NULL_TREE, |
011310f7 | 338 | LOOKUP_ONLYCONVERTING|DIRECT_BIND); |
1ad432f2 | 339 | } |
049132bc | 340 | else if (!(flags & DIRECT_BIND) && ! obvalue_p (arg)) |
44189c16 | 341 | return get_target_expr_sfinae (arg, complain); |
1ad432f2 | 342 | |
ca106ab1 | 343 | /* If we had a way to wrap this up, and say, if we ever needed its |
b0df6589 | 344 | address, transform all occurrences of the register, into a memory |
345 | reference we could win better. */ | |
44189c16 | 346 | rval = cp_build_addr_expr (arg, complain); |
15e55420 | 347 | if (rval == error_mark_node) |
348 | return error_mark_node; | |
349 | ||
6686e84d | 350 | if ((flags & LOOKUP_PROTECT) |
351 | && TYPE_MAIN_VARIANT (argtype) != TYPE_MAIN_VARIANT (target_type) | |
95397ff9 | 352 | && MAYBE_CLASS_TYPE_P (argtype) |
353 | && MAYBE_CLASS_TYPE_P (target_type)) | |
6686e84d | 354 | { |
7e6960e0 | 355 | /* We go through lookup_base for the access control. */ |
ae260dcc | 356 | tree binfo = lookup_base (argtype, target_type, ba_check, |
357 | NULL, complain); | |
6686e84d | 358 | if (binfo == error_mark_node) |
359 | return error_mark_node; | |
360 | if (binfo == NULL_TREE) | |
361 | return error_not_base_type (target_type, argtype); | |
c4698a21 | 362 | rval = build_base_path (PLUS_EXPR, rval, binfo, 1, complain); |
6686e84d | 363 | } |
c76251c1 | 364 | else |
365 | rval | |
c4698a21 | 366 | = convert_to_pointer_force (build_pointer_type (target_type), |
367 | rval, complain); | |
8999978b | 368 | return build_nop (type, rval); |
471086d6 | 369 | } |
370 | ||
519ba62c | 371 | /* Subroutine of convert_to_reference. REFTYPE is the target reference type. |
372 | INTYPE is the original rvalue type and DECL is an optional _DECL node | |
373 | for diagnostics. | |
9031d10b | 374 | |
519ba62c | 375 | [dcl.init.ref] says that if an rvalue is used to |
376 | initialize a reference, then the reference must be to a | |
377 | non-volatile const type. */ | |
378 | ||
379 | static void | |
19b271a9 | 380 | diagnose_ref_binding (location_t loc, tree reftype, tree intype, tree decl) |
519ba62c | 381 | { |
382 | tree ttl = TREE_TYPE (reftype); | |
9031d10b | 383 | |
519ba62c | 384 | if (!CP_TYPE_CONST_NON_VOLATILE_P (ttl)) |
385 | { | |
386 | const char *msg; | |
387 | ||
388 | if (CP_TYPE_VOLATILE_P (ttl) && decl) | |
ca82e026 | 389 | msg = G_("initialization of volatile reference type %q#T from " |
390 | "rvalue of type %qT"); | |
519ba62c | 391 | else if (CP_TYPE_VOLATILE_P (ttl)) |
ca82e026 | 392 | msg = G_("conversion to volatile reference type %q#T " |
393 | "from rvalue of type %qT"); | |
519ba62c | 394 | else if (decl) |
ca82e026 | 395 | msg = G_("initialization of non-const reference type %q#T from " |
396 | "rvalue of type %qT"); | |
519ba62c | 397 | else |
ca82e026 | 398 | msg = G_("conversion to non-const reference type %q#T from " |
399 | "rvalue of type %qT"); | |
519ba62c | 400 | |
61f69bc9 | 401 | permerror (loc, msg, reftype, intype); |
519ba62c | 402 | } |
403 | } | |
404 | ||
471086d6 | 405 | /* For C++: Only need to do one-level references, but cannot |
406 | get tripped up on signed/unsigned differences. | |
407 | ||
d81e00a4 | 408 | DECL is either NULL_TREE or the _DECL node for a reference that is being |
409 | initialized. It can be error_mark_node if we don't know the _DECL but | |
410 | we know it's an initialization. */ | |
471086d6 | 411 | |
471086d6 | 412 | tree |
35771a9a | 413 | convert_to_reference (tree reftype, tree expr, int convtype, |
c4698a21 | 414 | int flags, tree decl, tsubst_flags_t complain) |
471086d6 | 415 | { |
cd16867a | 416 | tree type = TYPE_MAIN_VARIANT (TREE_TYPE (reftype)); |
417 | tree intype; | |
471086d6 | 418 | tree rval = NULL_TREE; |
1a3f833b | 419 | tree rval_as_conversion = NULL_TREE; |
1bc16cab | 420 | bool can_convert_intype_to_type; |
3df42822 | 421 | location_t loc = EXPR_LOC_OR_LOC (expr, input_location); |
1a3f833b | 422 | |
9031d10b | 423 | if (TREE_CODE (type) == FUNCTION_TYPE |
d32df6a6 | 424 | && TREE_TYPE (expr) == unknown_type_node) |
66bbeb85 | 425 | expr = instantiate_type (type, expr, complain); |
0a3b29ad | 426 | |
427 | if (expr == error_mark_node) | |
428 | return error_mark_node; | |
429 | ||
430 | intype = TREE_TYPE (expr); | |
cc4d0855 | 431 | |
b4df430b | 432 | gcc_assert (TREE_CODE (intype) != REFERENCE_TYPE); |
ab12ed55 | 433 | gcc_assert (TREE_CODE (reftype) == REFERENCE_TYPE); |
471086d6 | 434 | |
471086d6 | 435 | intype = TYPE_MAIN_VARIANT (intype); |
436 | ||
b657f346 | 437 | can_convert_intype_to_type = can_convert_standard (type, intype, complain); |
66bbeb85 | 438 | |
1bc16cab | 439 | if (!can_convert_intype_to_type |
95397ff9 | 440 | && (convtype & CONV_IMPLICIT) && MAYBE_CLASS_TYPE_P (intype) |
1a3f833b | 441 | && ! (flags & LOOKUP_NO_CONVERSION)) |
442 | { | |
443 | /* Look for a user-defined conversion to lvalue that we can use. */ | |
444 | ||
0a4be248 | 445 | rval_as_conversion |
8999978b | 446 | = build_type_conversion (reftype, expr); |
1a3f833b | 447 | |
448 | if (rval_as_conversion && rval_as_conversion != error_mark_node | |
18bede74 | 449 | && lvalue_p (rval_as_conversion)) |
1a3f833b | 450 | { |
451 | expr = rval_as_conversion; | |
452 | rval_as_conversion = NULL_TREE; | |
453 | intype = type; | |
1bc16cab | 454 | can_convert_intype_to_type = 1; |
1a3f833b | 455 | } |
456 | } | |
457 | ||
b657f346 | 458 | if (((convtype & CONV_STATIC) |
459 | && can_convert_standard (intype, type, complain)) | |
1bc16cab | 460 | || ((convtype & CONV_IMPLICIT) && can_convert_intype_to_type)) |
471086d6 | 461 | { |
c4698a21 | 462 | { |
463 | tree ttl = TREE_TYPE (reftype); | |
464 | tree ttr = lvalue_type (expr); | |
471086d6 | 465 | |
19b271a9 | 466 | if ((complain & tf_error) |
18bede74 | 467 | && ! lvalue_p (expr)) |
19b271a9 | 468 | diagnose_ref_binding (loc, reftype, intype, decl); |
9031d10b | 469 | |
c4698a21 | 470 | if (! (convtype & CONV_CONST) |
471 | && !at_least_as_qualified_p (ttl, ttr)) | |
472 | { | |
473 | if (complain & tf_error) | |
4d1eda3a | 474 | permerror (loc, "conversion from %qH to %qI discards qualifiers", |
c4698a21 | 475 | ttr, reftype); |
476 | else | |
477 | return error_mark_node; | |
478 | } | |
479 | } | |
0543e7a9 | 480 | |
c4698a21 | 481 | return build_up_reference (reftype, expr, flags, decl, complain); |
471086d6 | 482 | } |
049132bc | 483 | else if ((convtype & CONV_REINTERPRET) && obvalue_p (expr)) |
0543e7a9 | 484 | { |
485 | /* When casting an lvalue to a reference type, just convert into | |
486 | a pointer to the new type and deference it. This is allowed | |
e581f478 | 487 | by San Diego WP section 5.2.9 paragraph 12, though perhaps it |
0543e7a9 | 488 | should be done directly (jason). (int &)ri ---> *(int*)&ri */ |
e581f478 | 489 | |
3748625f | 490 | /* B* bp; A& ar = (A&)bp; is valid, but it's probably not what they |
653e5405 | 491 | meant. */ |
c4698a21 | 492 | if ((complain & tf_warning) |
c21c015b | 493 | && TYPE_PTR_P (intype) |
a09db423 | 494 | && (comptypes (TREE_TYPE (intype), type, |
495 | COMPARE_BASE | COMPARE_DERIVED))) | |
61f69bc9 | 496 | warning_at (loc, 0, "casting %qT to %qT does not dereference pointer", |
497 | intype, reftype); | |
9031d10b | 498 | |
c4698a21 | 499 | rval = cp_build_addr_expr (expr, complain); |
0543e7a9 | 500 | if (rval != error_mark_node) |
985e9ee0 | 501 | rval = convert_force (build_pointer_type (TREE_TYPE (reftype)), |
c4698a21 | 502 | rval, 0, complain); |
0543e7a9 | 503 | if (rval != error_mark_node) |
b0722fac | 504 | rval = build1 (NOP_EXPR, reftype, rval); |
0543e7a9 | 505 | } |
0a4be248 | 506 | else |
860740a7 | 507 | { |
508 | rval = convert_for_initialization (NULL_TREE, type, expr, flags, | |
c4698a21 | 509 | ICR_CONVERTING, 0, 0, complain); |
a66fe4cb | 510 | if (rval == NULL_TREE || rval == error_mark_node) |
511 | return rval; | |
19b271a9 | 512 | if (complain & tf_error) |
513 | diagnose_ref_binding (loc, reftype, intype, decl); | |
c4698a21 | 514 | rval = build_up_reference (reftype, rval, flags, decl, complain); |
860740a7 | 515 | } |
471086d6 | 516 | |
517 | if (rval) | |
518 | { | |
96624a9e | 519 | /* If we found a way to convert earlier, then use it. */ |
471086d6 | 520 | return rval; |
521 | } | |
522 | ||
c4698a21 | 523 | if (complain & tf_error) |
4d1eda3a | 524 | error_at (loc, "cannot convert type %qH to type %qI", intype, reftype); |
b248d3f7 | 525 | |
471086d6 | 526 | return error_mark_node; |
527 | } | |
528 | ||
529 | /* We are using a reference VAL for its value. Bash that reference all the | |
96624a9e | 530 | way down to its lowest form. */ |
531 | ||
471086d6 | 532 | tree |
35771a9a | 533 | convert_from_reference (tree val) |
471086d6 | 534 | { |
73bdcca2 | 535 | if (TREE_TYPE (val) |
536 | && TREE_CODE (TREE_TYPE (val)) == REFERENCE_TYPE) | |
729f89ff | 537 | { |
2fb61329 | 538 | tree t = TREE_TYPE (TREE_TYPE (val)); |
729f89ff | 539 | tree ref = build1 (INDIRECT_REF, t, val); |
9031d10b | 540 | |
3d37a176 | 541 | mark_exp_read (val); |
729f89ff | 542 | /* We *must* set TREE_READONLY when dereferencing a pointer to const, |
543 | so that we get the proper error message if the result is used | |
544 | to assign to. Also, &* is supposed to be a no-op. */ | |
545 | TREE_READONLY (ref) = CP_TYPE_CONST_P (t); | |
546 | TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t); | |
547 | TREE_SIDE_EFFECTS (ref) | |
548 | = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (val)); | |
729f89ff | 549 | val = ref; |
550 | } | |
9031d10b | 551 | |
471086d6 | 552 | return val; |
553 | } | |
e5dab226 | 554 | |
555 | /* Really perform an lvalue-to-rvalue conversion, including copying an | |
556 | argument of class type into a temporary. */ | |
557 | ||
558 | tree | |
9e505437 | 559 | force_rvalue (tree expr, tsubst_flags_t complain) |
e5dab226 | 560 | { |
9e505437 | 561 | tree type = TREE_TYPE (expr); |
562 | if (MAYBE_CLASS_TYPE_P (type) && TREE_CODE (expr) != TARGET_EXPR) | |
563 | { | |
f1f41a6c | 564 | vec<tree, va_gc> *args = make_tree_vector_single (expr); |
9e505437 | 565 | expr = build_special_member_call (NULL_TREE, complete_ctor_identifier, |
566 | &args, type, LOOKUP_NORMAL, complain); | |
567 | release_tree_vector (args); | |
568 | expr = build_cplus_new (type, expr, complain); | |
569 | } | |
e5dab226 | 570 | else |
4405c1ad | 571 | expr = decay_conversion (expr, complain); |
e5dab226 | 572 | |
573 | return expr; | |
574 | } | |
f5220369 | 575 | |
471086d6 | 576 | \f |
a1f05651 | 577 | /* If EXPR and ORIG are INTEGER_CSTs, return a version of EXPR that has |
578 | TREE_OVERFLOW set only if it is set in ORIG. Otherwise, return EXPR | |
579 | unchanged. */ | |
580 | ||
581 | static tree | |
582 | ignore_overflows (tree expr, tree orig) | |
583 | { | |
584 | if (TREE_CODE (expr) == INTEGER_CST | |
585 | && TREE_CODE (orig) == INTEGER_CST | |
586 | && TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig)) | |
587 | { | |
588 | gcc_assert (!TREE_OVERFLOW (orig)); | |
589 | /* Ensure constant sharing. */ | |
e3d0f65c | 590 | expr = wide_int_to_tree (TREE_TYPE (expr), wi::to_wide (expr)); |
a1f05651 | 591 | } |
592 | return expr; | |
593 | } | |
594 | ||
595 | /* Fold away simple conversions, but make sure TREE_OVERFLOW is set | |
596 | properly. */ | |
f5220369 | 597 | |
598 | tree | |
599 | cp_fold_convert (tree type, tree expr) | |
600 | { | |
fe565588 | 601 | tree conv; |
602 | if (TREE_TYPE (expr) == type) | |
603 | conv = expr; | |
b6f86387 | 604 | else if (TREE_CODE (expr) == PTRMEM_CST) |
fe565588 | 605 | { |
606 | /* Avoid wrapping a PTRMEM_CST in NOP_EXPR. */ | |
607 | conv = copy_node (expr); | |
608 | TREE_TYPE (conv) = type; | |
609 | } | |
b6f86387 | 610 | else if (TREE_CODE (expr) == CONSTRUCTOR |
611 | && TYPE_PTRMEMFUNC_P (type)) | |
612 | conv = build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr, | |
613 | true, false, tf_warning_or_error); | |
fe565588 | 614 | else |
615 | { | |
616 | conv = fold_convert (type, expr); | |
617 | conv = ignore_overflows (conv, expr); | |
618 | } | |
a1f05651 | 619 | return conv; |
f5220369 | 620 | } |
621 | ||
c4a8ac95 | 622 | /* C++ conversions, preference to static cast conversions. */ |
623 | ||
624 | tree | |
c4698a21 | 625 | cp_convert (tree type, tree expr, tsubst_flags_t complain) |
c4a8ac95 | 626 | { |
c4698a21 | 627 | return ocp_convert (type, expr, CONV_OLD_CONVERT, LOOKUP_NORMAL, complain); |
c4a8ac95 | 628 | } |
629 | ||
59dd8856 | 630 | /* C++ equivalent of convert_and_check but using cp_convert as the |
631 | conversion function. | |
632 | ||
633 | Convert EXPR to TYPE, warning about conversion problems with constants. | |
634 | Invoke this function on every expression that is converted implicitly, | |
635 | i.e. because of language rules and not because of an explicit cast. */ | |
636 | ||
637 | tree | |
c4698a21 | 638 | cp_convert_and_check (tree type, tree expr, tsubst_flags_t complain) |
59dd8856 | 639 | { |
640 | tree result; | |
641 | ||
642 | if (TREE_TYPE (expr) == type) | |
643 | return expr; | |
d2c63826 | 644 | if (expr == error_mark_node) |
645 | return expr; | |
c4698a21 | 646 | result = cp_convert (type, expr, complain); |
59dd8856 | 647 | |
c4698a21 | 648 | if ((complain & tf_warning) |
65615944 | 649 | && c_inhibit_evaluation_warnings == 0) |
650 | { | |
d2c63826 | 651 | tree folded = cp_fully_fold (expr); |
652 | tree folded_result; | |
653 | if (folded == expr) | |
654 | folded_result = result; | |
655 | else | |
656 | { | |
657 | /* Avoid bogus -Wparentheses warnings. */ | |
93a735ed | 658 | warning_sentinel w (warn_parentheses); |
bed03df1 | 659 | warning_sentinel c (warn_int_in_bool_context); |
d2c63826 | 660 | folded_result = cp_convert (type, folded, tf_none); |
661 | } | |
662 | folded_result = fold_simple (folded_result); | |
663 | if (!TREE_OVERFLOW_P (folded) | |
65615944 | 664 | && folded_result != error_mark_node) |
3d27a0fa | 665 | warnings_for_convert_and_check (EXPR_LOC_OR_LOC (expr, input_location), |
666 | type, folded, folded_result); | |
65615944 | 667 | } |
59dd8856 | 668 | |
669 | return result; | |
670 | } | |
671 | ||
b248d3f7 | 672 | /* Conversion... |
673 | ||
674 | FLAGS indicates how we should behave. */ | |
675 | ||
471086d6 | 676 | tree |
c4698a21 | 677 | ocp_convert (tree type, tree expr, int convtype, int flags, |
678 | tsubst_flags_t complain) | |
471086d6 | 679 | { |
cd16867a | 680 | tree e = expr; |
681 | enum tree_code code = TREE_CODE (type); | |
7a979707 | 682 | const char *invalid_conv_diag; |
2b3c93a3 | 683 | tree e1; |
3df42822 | 684 | location_t loc = EXPR_LOC_OR_LOC (expr, input_location); |
b981525c | 685 | bool dofold = (convtype & CONV_FOLD); |
471086d6 | 686 | |
1bc16cab | 687 | if (error_operand_p (e) || type == error_mark_node) |
471086d6 | 688 | return error_mark_node; |
d81e00a4 | 689 | |
5b592939 | 690 | complete_type (type); |
691 | complete_type (TREE_TYPE (expr)); | |
692 | ||
7a979707 | 693 | if ((invalid_conv_diag |
694 | = targetm.invalid_conversion (TREE_TYPE (expr), type))) | |
695 | { | |
c4698a21 | 696 | if (complain & tf_error) |
697 | error (invalid_conv_diag); | |
7a979707 | 698 | return error_mark_node; |
699 | } | |
700 | ||
ce984e5e | 701 | /* FIXME remove when moving to c_fully_fold model. */ |
0a7452a8 | 702 | if (!CLASS_TYPE_P (type)) |
f3d71480 | 703 | { |
704 | e = mark_rvalue_use (e); | |
705 | e = scalar_constant_value (e); | |
706 | } | |
7a00f939 | 707 | if (error_operand_p (e)) |
708 | return error_mark_node; | |
7745052b | 709 | |
c821ae1a | 710 | if (MAYBE_CLASS_TYPE_P (type) && (convtype & CONV_FORCE_TEMP)) |
ceab25e5 | 711 | /* We need a new temporary; don't take this shortcut. */; |
930e8175 | 712 | else if (same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (e))) |
ca23ec64 | 713 | { |
daf9ff67 | 714 | if (same_type_p (type, TREE_TYPE (e))) |
ca23ec64 | 715 | /* The call to fold will not always remove the NOP_EXPR as |
716 | might be expected, since if one of the types is a typedef; | |
755edffd | 717 | the comparison in fold is just equality of pointers, not a |
a09db423 | 718 | call to comptypes. We don't call fold in this case because |
f699c174 | 719 | that can result in infinite recursion; fold will call |
720 | convert, which will call ocp_convert, etc. */ | |
721 | return e; | |
372e0e29 | 722 | /* For complex data types, we need to perform componentwise |
653e5405 | 723 | conversion. */ |
372e0e29 | 724 | else if (TREE_CODE (type) == COMPLEX_TYPE) |
b981525c | 725 | return convert_to_complex_maybe_fold (type, e, dofold); |
76249021 | 726 | else if (VECTOR_TYPE_P (type)) |
d2c63826 | 727 | return convert_to_vector (type, e); |
bdb2219e | 728 | else if (TREE_CODE (e) == TARGET_EXPR) |
729 | { | |
730 | /* Don't build a NOP_EXPR of class type. Instead, change the | |
930e8175 | 731 | type of the temporary. */ |
bdb2219e | 732 | TREE_TYPE (e) = TREE_TYPE (TARGET_EXPR_SLOT (e)) = type; |
733 | return e; | |
734 | } | |
ca23ec64 | 735 | else |
092b1d6f | 736 | { |
737 | /* We shouldn't be treating objects of ADDRESSABLE type as | |
738 | rvalues. */ | |
739 | gcc_assert (!TREE_ADDRESSABLE (type)); | |
d2c63826 | 740 | return build_nop (type, e); |
092b1d6f | 741 | } |
ca23ec64 | 742 | } |
743 | ||
2b3c93a3 | 744 | e1 = targetm.convert_to_type (type, e); |
745 | if (e1) | |
746 | return e1; | |
747 | ||
d81e00a4 | 748 | if (code == VOID_TYPE && (convtype & CONV_STATIC)) |
95b2ac55 | 749 | { |
c4698a21 | 750 | e = convert_to_void (e, ICV_CAST, complain); |
aeef2be5 | 751 | return e; |
95b2ac55 | 752 | } |
d81e00a4 | 753 | |
bb0726a1 | 754 | if (INTEGRAL_CODE_P (code)) |
471086d6 | 755 | { |
617abf06 | 756 | tree intype = TREE_TYPE (e); |
a1f05651 | 757 | tree converted; |
384590d4 | 758 | |
759 | if (TREE_CODE (type) == ENUMERAL_TYPE) | |
760 | { | |
761 | /* enum = enum, enum = int, enum = float, (enum)pointer are all | |
762 | errors. */ | |
763 | if (((INTEGRAL_OR_ENUMERATION_TYPE_P (intype) | |
653e5405 | 764 | || TREE_CODE (intype) == REAL_TYPE) |
b312a686 | 765 | && ! (convtype & CONV_STATIC)) |
c21c015b | 766 | || TYPE_PTR_P (intype)) |
384590d4 | 767 | { |
c4698a21 | 768 | if (complain & tf_error) |
61f69bc9 | 769 | permerror (loc, "conversion from %q#T to %q#T", intype, type); |
c4698a21 | 770 | else |
384590d4 | 771 | return error_mark_node; |
772 | } | |
773 | ||
774 | /* [expr.static.cast] | |
775 | ||
776 | 8. A value of integral or enumeration type can be explicitly | |
777 | converted to an enumeration type. The value is unchanged if | |
778 | the original value is within the range of the enumeration | |
779 | values. Otherwise, the resulting enumeration value is | |
780 | unspecified. */ | |
c4698a21 | 781 | if ((complain & tf_warning) |
c28ddc97 | 782 | && TREE_CODE (e) == INTEGER_CST |
0116c9f8 | 783 | && ENUM_UNDERLYING_TYPE (type) |
c28ddc97 | 784 | && !int_fits_type_p (e, ENUM_UNDERLYING_TYPE (type))) |
61f69bc9 | 785 | warning_at (loc, OPT_Wconversion, |
786 | "the result of the conversion is unspecified because " | |
787 | "%qE is outside the range of type %qT", | |
788 | expr, type); | |
471086d6 | 789 | } |
95397ff9 | 790 | if (MAYBE_CLASS_TYPE_P (intype)) |
471086d6 | 791 | { |
792 | tree rval; | |
8999978b | 793 | rval = build_type_conversion (type, e); |
6495357a | 794 | if (rval) |
795 | return rval; | |
c4698a21 | 796 | if (complain & tf_error) |
61f69bc9 | 797 | error_at (loc, "%q#T used where a %qT was expected", intype, type); |
471086d6 | 798 | return error_mark_node; |
799 | } | |
bb0726a1 | 800 | if (code == BOOLEAN_TYPE) |
f8913d47 | 801 | { |
c21c015b | 802 | if (VOID_TYPE_P (intype)) |
61f69bc9 | 803 | { |
c4698a21 | 804 | if (complain & tf_error) |
805 | error_at (loc, | |
806 | "could not convert %qE from %<void%> to %<bool%>", | |
807 | expr); | |
61f69bc9 | 808 | return error_mark_node; |
809 | } | |
810 | ||
f8913d47 | 811 | /* We can't implicitly convert a scoped enum to bool, so convert |
812 | to the underlying type first. */ | |
813 | if (SCOPED_ENUM_P (intype) && (convtype & CONV_STATIC)) | |
172fff7b | 814 | e = build_nop (ENUM_UNDERLYING_TYPE (intype), e); |
493196c0 | 815 | if (complain & tf_warning) |
816 | return cp_truthvalue_conversion (e); | |
817 | else | |
818 | { | |
819 | /* Prevent bogus -Wint-in-bool-context warnings coming | |
820 | from c_common_truthvalue_conversion down the line. */ | |
821 | warning_sentinel w (warn_int_in_bool_context); | |
822 | return cp_truthvalue_conversion (e); | |
823 | } | |
f8913d47 | 824 | } |
ce871053 | 825 | |
b981525c | 826 | converted = convert_to_integer_maybe_fold (type, e, dofold); |
a1f05651 | 827 | |
828 | /* Ignore any integer overflow caused by the conversion. */ | |
829 | return ignore_overflows (converted, e); | |
471086d6 | 830 | } |
c7ca48ea | 831 | if (NULLPTR_TYPE_P (type) && e && null_ptr_cst_p (e)) |
49858f84 | 832 | { |
833 | if (complain & tf_warning) | |
834 | maybe_warn_zero_as_null_pointer_constant (e, loc); | |
835 | return nullptr_node; | |
836 | } | |
05765a91 | 837 | if (POINTER_TYPE_P (type) || TYPE_PTRMEM_P (type)) |
b981525c | 838 | return cp_convert_to_pointer (type, e, dofold, complain); |
684b9d79 | 839 | if (code == VECTOR_TYPE) |
c37ff371 | 840 | { |
841 | tree in_vtype = TREE_TYPE (e); | |
95397ff9 | 842 | if (MAYBE_CLASS_TYPE_P (in_vtype)) |
c37ff371 | 843 | { |
844 | tree ret_val; | |
845 | ret_val = build_type_conversion (type, e); | |
653e5405 | 846 | if (ret_val) |
847 | return ret_val; | |
c4698a21 | 848 | if (complain & tf_error) |
849 | error_at (loc, "%q#T used where a %qT was expected", | |
850 | in_vtype, type); | |
653e5405 | 851 | return error_mark_node; |
c37ff371 | 852 | } |
d2c63826 | 853 | return convert_to_vector (type, e); |
c37ff371 | 854 | } |
c4a8ac95 | 855 | if (code == REAL_TYPE || code == COMPLEX_TYPE) |
471086d6 | 856 | { |
95397ff9 | 857 | if (MAYBE_CLASS_TYPE_P (TREE_TYPE (e))) |
471086d6 | 858 | { |
859 | tree rval; | |
8999978b | 860 | rval = build_type_conversion (type, e); |
471086d6 | 861 | if (rval) |
862 | return rval; | |
c4698a21 | 863 | else if (complain & tf_error) |
864 | error_at (loc, | |
865 | "%q#T used where a floating point value was expected", | |
866 | TREE_TYPE (e)); | |
471086d6 | 867 | } |
c4a8ac95 | 868 | if (code == REAL_TYPE) |
b981525c | 869 | return convert_to_real_maybe_fold (type, e, dofold); |
c4a8ac95 | 870 | else if (code == COMPLEX_TYPE) |
b981525c | 871 | return convert_to_complex_maybe_fold (type, e, dofold); |
471086d6 | 872 | } |
873 | ||
874 | /* New C++ semantics: since assignment is now based on | |
875 | memberwise copying, if the rhs type is derived from the | |
876 | lhs type, then we may still do a conversion. */ | |
95397ff9 | 877 | if (RECORD_OR_UNION_CODE_P (code)) |
471086d6 | 878 | { |
879 | tree dtype = TREE_TYPE (e); | |
c25194fd | 880 | tree ctor = NULL_TREE; |
471086d6 | 881 | |
471086d6 | 882 | dtype = TYPE_MAIN_VARIANT (dtype); |
883 | ||
471086d6 | 884 | /* Conversion between aggregate types. New C++ semantics allow |
885 | objects of derived type to be cast to objects of base type. | |
886 | Old semantics only allowed this between pointers. | |
887 | ||
888 | There may be some ambiguity between using a constructor | |
889 | vs. using a type conversion operator when both apply. */ | |
890 | ||
0a4be248 | 891 | ctor = e; |
860740a7 | 892 | |
44189c16 | 893 | if (abstract_virtuals_error_sfinae (NULL_TREE, type, complain)) |
8c18e707 | 894 | return error_mark_node; |
6cbb4197 | 895 | |
f82f1250 | 896 | if (BRACE_ENCLOSED_INITIALIZER_P (ctor)) |
c4698a21 | 897 | ctor = perform_implicit_conversion (type, ctor, complain); |
f82f1250 | 898 | else if ((flags & LOOKUP_ONLYCONVERTING) |
899 | && ! (CLASS_TYPE_P (dtype) && DERIVED_FROM_P (type, dtype))) | |
fce73460 | 900 | /* For copy-initialization, first we create a temp of the proper type |
901 | with a user-defined conversion sequence, then we direct-initialize | |
902 | the target with the temp (see [dcl.init]). */ | |
c4698a21 | 903 | ctor = build_user_type_conversion (type, ctor, flags, complain); |
3eb89cd8 | 904 | else |
f352a3fb | 905 | { |
f1f41a6c | 906 | vec<tree, va_gc> *ctor_vec = make_tree_vector_single (ctor); |
f352a3fb | 907 | ctor = build_special_member_call (NULL_TREE, |
908 | complete_ctor_identifier, | |
909 | &ctor_vec, | |
c4698a21 | 910 | type, flags, complain); |
f352a3fb | 911 | release_tree_vector (ctor_vec); |
912 | } | |
0a4be248 | 913 | if (ctor) |
c4698a21 | 914 | return build_cplus_new (type, ctor, complain); |
471086d6 | 915 | } |
916 | ||
c4698a21 | 917 | if (complain & tf_error) |
a7cc1549 | 918 | { |
919 | /* If the conversion failed and expr was an invalid use of pointer to | |
920 | member function, try to report a meaningful error. */ | |
5c874cd3 | 921 | if (invalid_nonstatic_memfn_p (loc, expr, complain)) |
a7cc1549 | 922 | /* We displayed the error message. */; |
923 | else | |
4d1eda3a | 924 | error_at (loc, "conversion from %qH to non-scalar type %qI requested", |
61f69bc9 | 925 | TREE_TYPE (expr), type); |
a7cc1549 | 926 | } |
471086d6 | 927 | return error_mark_node; |
928 | } | |
929 | ||
3ae3cb42 | 930 | /* If CALL is a call, return the callee; otherwise null. */ |
931 | ||
932 | tree | |
933 | cp_get_callee (tree call) | |
934 | { | |
935 | if (call == NULL_TREE) | |
936 | return call; | |
937 | else if (TREE_CODE (call) == CALL_EXPR) | |
938 | return CALL_EXPR_FN (call); | |
939 | else if (TREE_CODE (call) == AGGR_INIT_EXPR) | |
940 | return AGGR_INIT_EXPR_FN (call); | |
941 | return NULL_TREE; | |
942 | } | |
943 | ||
ddd2a3d4 | 944 | /* FN is the callee of a CALL_EXPR or AGGR_INIT_EXPR; return the FUNCTION_DECL |
945 | if we can. */ | |
946 | ||
947 | tree | |
ced7e116 | 948 | cp_get_fndecl_from_callee (tree fn, bool fold /* = true */) |
ddd2a3d4 | 949 | { |
950 | if (fn == NULL_TREE) | |
951 | return fn; | |
952 | if (TREE_CODE (fn) == FUNCTION_DECL) | |
953 | return fn; | |
954 | tree type = TREE_TYPE (fn); | |
955 | if (type == unknown_type_node) | |
956 | return NULL_TREE; | |
957 | gcc_assert (POINTER_TYPE_P (type)); | |
ced7e116 | 958 | if (fold) |
959 | fn = maybe_constant_init (fn); | |
ddd2a3d4 | 960 | STRIP_NOPS (fn); |
961 | if (TREE_CODE (fn) == ADDR_EXPR) | |
962 | { | |
963 | fn = TREE_OPERAND (fn, 0); | |
964 | if (TREE_CODE (fn) == FUNCTION_DECL) | |
965 | return fn; | |
966 | } | |
967 | return NULL_TREE; | |
968 | } | |
969 | ||
970 | /* Like get_callee_fndecl, but handles AGGR_INIT_EXPR as well and uses the | |
971 | constexpr machinery. */ | |
972 | ||
973 | tree | |
974 | cp_get_callee_fndecl (tree call) | |
975 | { | |
976 | return cp_get_fndecl_from_callee (cp_get_callee (call)); | |
977 | } | |
978 | ||
ced7e116 | 979 | /* As above, but not using the constexpr machinery. */ |
980 | ||
981 | tree | |
982 | cp_get_callee_fndecl_nofold (tree call) | |
983 | { | |
984 | return cp_get_fndecl_from_callee (cp_get_callee (call), false); | |
985 | } | |
986 | ||
ddd2a3d4 | 987 | /* Subroutine of convert_to_void. Warn if we're discarding something with |
988 | attribute [[nodiscard]]. */ | |
989 | ||
990 | static void | |
991 | maybe_warn_nodiscard (tree expr, impl_conv_void implicit) | |
992 | { | |
993 | tree call = expr; | |
994 | if (TREE_CODE (expr) == TARGET_EXPR) | |
995 | call = TARGET_EXPR_INITIAL (expr); | |
996 | location_t loc = EXPR_LOC_OR_LOC (call, input_location); | |
997 | tree callee = cp_get_callee (call); | |
998 | if (!callee) | |
999 | return; | |
1000 | ||
1001 | tree type = TREE_TYPE (callee); | |
1002 | if (TYPE_PTRMEMFUNC_P (type)) | |
1003 | type = TYPE_PTRMEMFUNC_FN_TYPE (type); | |
1004 | if (POINTER_TYPE_P (type)) | |
1005 | type = TREE_TYPE (type); | |
1006 | ||
1007 | tree rettype = TREE_TYPE (type); | |
1008 | tree fn = cp_get_fndecl_from_callee (callee); | |
1009 | if (implicit != ICV_CAST && fn | |
1010 | && lookup_attribute ("nodiscard", DECL_ATTRIBUTES (fn))) | |
1011 | { | |
1012 | if (warning_at (loc, OPT_Wunused_result, | |
1013 | "ignoring return value of %qD, " | |
1014 | "declared with attribute nodiscard", fn)) | |
1015 | inform (DECL_SOURCE_LOCATION (fn), "declared here"); | |
1016 | } | |
1017 | else if (implicit != ICV_CAST | |
1018 | && lookup_attribute ("nodiscard", TYPE_ATTRIBUTES (rettype))) | |
1019 | { | |
1020 | if (warning_at (loc, OPT_Wunused_result, | |
1021 | "ignoring returned value of type %qT, " | |
1022 | "declared with attribute nodiscard", rettype)) | |
1023 | { | |
1024 | if (fn) | |
1025 | inform (DECL_SOURCE_LOCATION (fn), | |
1026 | "in call to %qD, declared here", fn); | |
1027 | inform (DECL_SOURCE_LOCATION (TYPE_NAME (rettype)), | |
1028 | "%qT declared here", rettype); | |
1029 | } | |
1030 | } | |
1031 | else if (TREE_CODE (expr) == TARGET_EXPR | |
1032 | && lookup_attribute ("warn_unused_result", TYPE_ATTRIBUTES (type))) | |
1033 | { | |
1034 | /* The TARGET_EXPR confuses do_warn_unused_result into thinking that the | |
1035 | result is used, so handle that case here. */ | |
1036 | if (fn) | |
1037 | { | |
1038 | if (warning_at (loc, OPT_Wunused_result, | |
1039 | "ignoring return value of %qD, " | |
1040 | "declared with attribute warn_unused_result", | |
1041 | fn)) | |
1042 | inform (DECL_SOURCE_LOCATION (fn), "declared here"); | |
1043 | } | |
1044 | else | |
1045 | warning_at (loc, OPT_Wunused_result, | |
1046 | "ignoring return value of function " | |
1047 | "declared with attribute warn_unused_result"); | |
1048 | } | |
1049 | } | |
1050 | ||
b1a8d4ce | 1051 | /* When an expression is used in a void context, its value is discarded and |
1052 | no lvalue-rvalue and similar conversions happen [expr.static.cast/4, | |
1053 | stmt.expr/1, expr.comma/1]. This permits dereferencing an incomplete type | |
1054 | in a void context. The C++ standard does not define what an `access' to an | |
63eff20d | 1055 | object is, but there is reason to believe that it is the lvalue to rvalue |
b1a8d4ce | 1056 | conversion -- if it were not, `*&*p = 1' would violate [expr]/4 in that it |
1057 | accesses `*p' not to calculate the value to be stored. But, dcl.type.cv/8 | |
1058 | indicates that volatile semantics should be the same between C and C++ | |
1059 | where ever possible. C leaves it implementation defined as to what | |
1060 | constitutes an access to a volatile. So, we interpret `*vp' as a read of | |
1061 | the volatile object `vp' points to, unless that is an incomplete type. For | |
1062 | volatile references we do not do this interpretation, because that would | |
1063 | make it impossible to ignore the reference return value from functions. We | |
1064 | issue warnings in the confusing cases. | |
9031d10b | 1065 | |
dab3247a | 1066 | The IMPLICIT is ICV_CAST when the user is explicitly converting an expression |
1067 | to void via a cast. If an expression is being implicitly converted, IMPLICIT | |
1068 | indicates the context of the implicit conversion. */ | |
b1a8d4ce | 1069 | |
1070 | tree | |
dab3247a | 1071 | convert_to_void (tree expr, impl_conv_void implicit, tsubst_flags_t complain) |
b1a8d4ce | 1072 | { |
3df42822 | 1073 | location_t loc = EXPR_LOC_OR_LOC (expr, input_location); |
61f69bc9 | 1074 | |
9031d10b | 1075 | if (expr == error_mark_node |
3d411d73 | 1076 | || TREE_TYPE (expr) == error_mark_node) |
1077 | return error_mark_node; | |
b2af2a93 | 1078 | |
f4c5829e | 1079 | expr = maybe_undo_parenthesized_ref (expr); |
1080 | ||
c017458d | 1081 | expr = mark_discarded_use (expr); |
dab3247a | 1082 | if (implicit == ICV_CAST) |
c017458d | 1083 | /* An explicit cast to void avoids all -Wunused-but-set* warnings. */ |
f94341bb | 1084 | mark_exp_read (expr); |
b2af2a93 | 1085 | |
b1a8d4ce | 1086 | if (!TREE_TYPE (expr)) |
1087 | return expr; | |
5c874cd3 | 1088 | if (invalid_nonstatic_memfn_p (loc, expr, complain)) |
334f6ce1 | 1089 | return error_mark_node; |
ed36f1cf | 1090 | if (TREE_CODE (expr) == PSEUDO_DTOR_EXPR) |
1091 | { | |
ebd21de4 | 1092 | if (complain & tf_error) |
61f69bc9 | 1093 | error_at (loc, "pseudo-destructor is not called"); |
ed36f1cf | 1094 | return error_mark_node; |
1095 | } | |
e3cfe3ce | 1096 | if (VOID_TYPE_P (TREE_TYPE (expr))) |
b1a8d4ce | 1097 | return expr; |
1098 | switch (TREE_CODE (expr)) | |
1099 | { | |
1100 | case COND_EXPR: | |
1101 | { | |
653e5405 | 1102 | /* The two parts of a cond expr might be separate lvalues. */ |
1103 | tree op1 = TREE_OPERAND (expr,1); | |
1104 | tree op2 = TREE_OPERAND (expr,2); | |
527facbb | 1105 | bool side_effects = ((op1 && TREE_SIDE_EFFECTS (op1)) |
1106 | || TREE_SIDE_EFFECTS (op2)); | |
dab3247a | 1107 | tree new_op1, new_op2; |
527facbb | 1108 | new_op1 = NULL_TREE; |
dab3247a | 1109 | if (implicit != ICV_CAST && !side_effects) |
1110 | { | |
527facbb | 1111 | if (op1) |
1112 | new_op1 = convert_to_void (op1, ICV_SECOND_OF_COND, complain); | |
dab3247a | 1113 | new_op2 = convert_to_void (op2, ICV_THIRD_OF_COND, complain); |
1114 | } | |
1115 | else | |
1116 | { | |
527facbb | 1117 | if (op1) |
1118 | new_op1 = convert_to_void (op1, ICV_CAST, complain); | |
dab3247a | 1119 | new_op2 = convert_to_void (op2, ICV_CAST, complain); |
1120 | } | |
9031d10b | 1121 | |
527facbb | 1122 | expr = build3 (COND_EXPR, TREE_TYPE (new_op2), |
831d52a2 | 1123 | TREE_OPERAND (expr, 0), new_op1, new_op2); |
653e5405 | 1124 | break; |
b1a8d4ce | 1125 | } |
9031d10b | 1126 | |
b1a8d4ce | 1127 | case COMPOUND_EXPR: |
1128 | { | |
653e5405 | 1129 | /* The second part of a compound expr contains the value. */ |
1130 | tree op1 = TREE_OPERAND (expr,1); | |
dab3247a | 1131 | tree new_op1; |
1132 | if (implicit != ICV_CAST && !TREE_NO_WARNING (expr)) | |
1133 | new_op1 = convert_to_void (op1, ICV_RIGHT_OF_COMMA, complain); | |
1134 | else | |
1135 | new_op1 = convert_to_void (op1, ICV_CAST, complain); | |
9031d10b | 1136 | |
653e5405 | 1137 | if (new_op1 != op1) |
e907a2e9 | 1138 | { |
831d52a2 | 1139 | tree t = build2 (COMPOUND_EXPR, TREE_TYPE (new_op1), |
1140 | TREE_OPERAND (expr, 0), new_op1); | |
e907a2e9 | 1141 | expr = t; |
1142 | } | |
1143 | ||
653e5405 | 1144 | break; |
b1a8d4ce | 1145 | } |
9031d10b | 1146 | |
b1a8d4ce | 1147 | case NON_LVALUE_EXPR: |
1148 | case NOP_EXPR: | |
c0af329c | 1149 | /* These have already decayed to rvalue. */ |
b1a8d4ce | 1150 | break; |
9031d10b | 1151 | |
331bc0ad | 1152 | case CALL_EXPR: /* We have a special meaning for volatile void fn(). */ |
ddd2a3d4 | 1153 | maybe_warn_nodiscard (expr, implicit); |
b1a8d4ce | 1154 | break; |
9031d10b | 1155 | |
b1a8d4ce | 1156 | case INDIRECT_REF: |
1157 | { | |
653e5405 | 1158 | tree type = TREE_TYPE (expr); |
1159 | int is_reference = TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) | |
1160 | == REFERENCE_TYPE; | |
1161 | int is_volatile = TYPE_VOLATILE (type); | |
1162 | int is_complete = COMPLETE_TYPE_P (complete_type (type)); | |
1163 | ||
dc02da7f | 1164 | /* Can't load the value if we don't know the type. */ |
653e5405 | 1165 | if (is_volatile && !is_complete) |
ebd21de4 | 1166 | { |
1167 | if (complain & tf_warning) | |
dab3247a | 1168 | switch (implicit) |
1169 | { | |
1170 | case ICV_CAST: | |
61f69bc9 | 1171 | warning_at (loc, 0, "conversion to void will not access " |
dab3247a | 1172 | "object of incomplete type %qT", type); |
1173 | break; | |
1174 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1175 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1176 | "incomplete type %qT in second operand " |
1177 | "of conditional expression", type); | |
1178 | break; | |
1179 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1180 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1181 | "incomplete type %qT in third operand " |
1182 | "of conditional expression", type); | |
1183 | break; | |
1184 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1185 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1186 | "incomplete type %qT in right operand of " |
1187 | "comma operator", type); | |
1188 | break; | |
1189 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1190 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1191 | "incomplete type %qT in left operand of " |
1192 | "comma operator", type); | |
1193 | break; | |
1194 | case ICV_STATEMENT: | |
61f69bc9 | 1195 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1196 | "incomplete type %qT in statement", type); |
1197 | break; | |
1198 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1199 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1200 | "incomplete type %qT in for increment " |
1201 | "expression", type); | |
1202 | break; | |
1203 | default: | |
1204 | gcc_unreachable (); | |
1205 | } | |
ebd21de4 | 1206 | } |
dc02da7f | 1207 | /* Don't load the value if this is an implicit dereference, or if |
1208 | the type needs to be handled by ctors/dtors. */ | |
dab3247a | 1209 | else if (is_volatile && is_reference) |
ebd21de4 | 1210 | { |
1211 | if (complain & tf_warning) | |
dab3247a | 1212 | switch (implicit) |
1213 | { | |
1214 | case ICV_CAST: | |
61f69bc9 | 1215 | warning_at (loc, 0, "conversion to void will not access " |
dab3247a | 1216 | "object of type %qT", type); |
1217 | break; | |
1218 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1219 | warning_at (loc, 0, "implicit dereference will not access " |
1220 | "object of type %qT in second operand of " | |
dab3247a | 1221 | "conditional expression", type); |
1222 | break; | |
1223 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1224 | warning_at (loc, 0, "implicit dereference will not access " |
1225 | "object of type %qT in third operand of " | |
dab3247a | 1226 | "conditional expression", type); |
1227 | break; | |
1228 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1229 | warning_at (loc, 0, "implicit dereference will not access " |
1230 | "object of type %qT in right operand of " | |
dab3247a | 1231 | "comma operator", type); |
1232 | break; | |
1233 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1234 | warning_at (loc, 0, "implicit dereference will not access " |
1235 | "object of type %qT in left operand of comma " | |
1236 | "operator", type); | |
dab3247a | 1237 | break; |
1238 | case ICV_STATEMENT: | |
61f69bc9 | 1239 | warning_at (loc, 0, "implicit dereference will not access " |
1240 | "object of type %qT in statement", type); | |
dab3247a | 1241 | break; |
1242 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1243 | warning_at (loc, 0, "implicit dereference will not access " |
1244 | "object of type %qT in for increment expression", | |
1245 | type); | |
dab3247a | 1246 | break; |
1247 | default: | |
1248 | gcc_unreachable (); | |
1249 | } | |
ebd21de4 | 1250 | } |
dab3247a | 1251 | else if (is_volatile && TREE_ADDRESSABLE (type)) |
1252 | { | |
1253 | if (complain & tf_warning) | |
1254 | switch (implicit) | |
1255 | { | |
1256 | case ICV_CAST: | |
61f69bc9 | 1257 | warning_at (loc, 0, "conversion to void will not access " |
dab3247a | 1258 | "object of non-trivially-copyable type %qT", |
61f69bc9 | 1259 | type); |
dab3247a | 1260 | break; |
1261 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1262 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1263 | "non-trivially-copyable type %qT in second " |
1264 | "operand of conditional expression", type); | |
1265 | break; | |
1266 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1267 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1268 | "non-trivially-copyable type %qT in third " |
1269 | "operand of conditional expression", type); | |
1270 | break; | |
1271 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1272 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1273 | "non-trivially-copyable type %qT in right " |
1274 | "operand of comma operator", type); | |
1275 | break; | |
1276 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1277 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1278 | "non-trivially-copyable type %qT in left " |
1279 | "operand of comma operator", type); | |
1280 | break; | |
1281 | case ICV_STATEMENT: | |
61f69bc9 | 1282 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1283 | "non-trivially-copyable type %qT in statement", |
61f69bc9 | 1284 | type); |
dab3247a | 1285 | break; |
1286 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1287 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1288 | "non-trivially-copyable type %qT in for " |
1289 | "increment expression", type); | |
1290 | break; | |
1291 | default: | |
1292 | gcc_unreachable (); | |
1293 | } | |
1294 | } | |
dc02da7f | 1295 | if (is_reference || !is_volatile || !is_complete || TREE_ADDRESSABLE (type)) |
a4d4030b | 1296 | { |
1297 | /* Emit a warning (if enabled) when the "effect-less" INDIRECT_REF | |
1298 | operation is stripped off. Note that we don't warn about | |
1299 | - an expression with TREE_NO_WARNING set. (For an example of | |
1300 | such expressions, see build_over_call in call.c.) | |
1301 | - automatic dereferencing of references, since the user cannot | |
3d177e8c | 1302 | control it. (See also warn_if_unused_value() in c-common.c.) */ |
a4d4030b | 1303 | if (warn_unused_value |
dab3247a | 1304 | && implicit != ICV_CAST |
a4d4030b | 1305 | && (complain & tf_warning) |
1306 | && !TREE_NO_WARNING (expr) | |
1307 | && !is_reference) | |
61f69bc9 | 1308 | warning_at (loc, OPT_Wunused_value, "value computed is not used"); |
a4d4030b | 1309 | expr = TREE_OPERAND (expr, 0); |
409bb09c | 1310 | if (TREE_CODE (expr) == CALL_EXPR) |
1311 | maybe_warn_nodiscard (expr, implicit); | |
a4d4030b | 1312 | } |
653e5405 | 1313 | |
1314 | break; | |
b1a8d4ce | 1315 | } |
9031d10b | 1316 | |
b1a8d4ce | 1317 | case VAR_DECL: |
1318 | { | |
653e5405 | 1319 | /* External variables might be incomplete. */ |
1320 | tree type = TREE_TYPE (expr); | |
1321 | int is_complete = COMPLETE_TYPE_P (complete_type (type)); | |
1322 | ||
ebd21de4 | 1323 | if (TYPE_VOLATILE (type) && !is_complete && (complain & tf_warning)) |
dab3247a | 1324 | switch (implicit) |
1325 | { | |
1326 | case ICV_CAST: | |
61f69bc9 | 1327 | warning_at (loc, 0, "conversion to void will not access " |
dab3247a | 1328 | "object %qE of incomplete type %qT", expr, type); |
1329 | break; | |
1330 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1331 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1332 | "not be accessed in second operand of " | |
dab3247a | 1333 | "conditional expression", expr, type); |
1334 | break; | |
1335 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1336 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1337 | "not be accessed in third operand of " | |
dab3247a | 1338 | "conditional expression", expr, type); |
1339 | break; | |
1340 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1341 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1342 | "not be accessed in right operand of comma operator", | |
1343 | expr, type); | |
dab3247a | 1344 | break; |
1345 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1346 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1347 | "not be accessed in left operand of comma operator", | |
1348 | expr, type); | |
dab3247a | 1349 | break; |
1350 | case ICV_STATEMENT: | |
61f69bc9 | 1351 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1352 | "not be accessed in statement", expr, type); | |
dab3247a | 1353 | break; |
1354 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1355 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1356 | "not be accessed in for increment expression", | |
1357 | expr, type); | |
dab3247a | 1358 | break; |
1359 | default: | |
1360 | gcc_unreachable (); | |
1361 | } | |
1362 | ||
653e5405 | 1363 | break; |
b1a8d4ce | 1364 | } |
d9f88785 | 1365 | |
25b3017b | 1366 | case TARGET_EXPR: |
1367 | /* Don't bother with the temporary object returned from a function if | |
1fe75cf2 | 1368 | we don't use it, don't need to destroy it, and won't abort in |
1369 | assign_temp. We'll still | |
25b3017b | 1370 | allocate space for it in expand_call or declare_return_variable, |
1371 | but we don't need to track it through all the tree phases. */ | |
67bb1301 | 1372 | if (TARGET_EXPR_IMPLICIT_P (expr) |
1fe75cf2 | 1373 | && !TREE_ADDRESSABLE (TREE_TYPE (expr))) |
25b3017b | 1374 | { |
1375 | tree init = TARGET_EXPR_INITIAL (expr); | |
1376 | if (TREE_CODE (init) == AGGR_INIT_EXPR | |
1377 | && !AGGR_INIT_VIA_CTOR_P (init)) | |
1378 | { | |
c2f47e15 | 1379 | tree fn = AGGR_INIT_EXPR_FN (init); |
389dd41b | 1380 | expr = build_call_array_loc (input_location, |
ddd2a3d4 | 1381 | TREE_TYPE (TREE_TYPE |
1382 | (TREE_TYPE (fn))), | |
389dd41b | 1383 | fn, |
1384 | aggr_init_expr_nargs (init), | |
1385 | AGGR_INIT_EXPR_ARGP (init)); | |
25b3017b | 1386 | } |
1387 | } | |
ddd2a3d4 | 1388 | maybe_warn_nodiscard (expr, implicit); |
25b3017b | 1389 | break; |
1390 | ||
b1a8d4ce | 1391 | default:; |
1392 | } | |
703eb775 | 1393 | expr = resolve_nondeduced_context (expr, complain); |
b1a8d4ce | 1394 | { |
1395 | tree probe = expr; | |
9031d10b | 1396 | |
b1a8d4ce | 1397 | if (TREE_CODE (probe) == ADDR_EXPR) |
1398 | probe = TREE_OPERAND (expr, 0); | |
2e0e6579 | 1399 | if (type_unknown_p (probe)) |
1400 | { | |
1401 | /* [over.over] enumerates the places where we can take the address | |
1402 | of an overloaded function, and this is not one of them. */ | |
ebd21de4 | 1403 | if (complain & tf_error) |
dab3247a | 1404 | switch (implicit) |
1405 | { | |
1406 | case ICV_CAST: | |
61f69bc9 | 1407 | error_at (loc, "conversion to void " |
1408 | "cannot resolve address of overloaded function"); | |
dab3247a | 1409 | break; |
1410 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1411 | error_at (loc, "second operand of conditional expression " |
1412 | "cannot resolve address of overloaded function"); | |
dab3247a | 1413 | break; |
1414 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1415 | error_at (loc, "third operand of conditional expression " |
1416 | "cannot resolve address of overloaded function"); | |
dab3247a | 1417 | break; |
1418 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1419 | error_at (loc, "right operand of comma operator " |
1420 | "cannot resolve address of overloaded function"); | |
dab3247a | 1421 | break; |
1422 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1423 | error_at (loc, "left operand of comma operator " |
1424 | "cannot resolve address of overloaded function"); | |
dab3247a | 1425 | break; |
1426 | case ICV_STATEMENT: | |
61f69bc9 | 1427 | error_at (loc, "statement " |
1428 | "cannot resolve address of overloaded function"); | |
dab3247a | 1429 | break; |
1430 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1431 | error_at (loc, "for increment expression " |
1432 | "cannot resolve address of overloaded function"); | |
dab3247a | 1433 | break; |
1434 | } | |
ebd21de4 | 1435 | else |
1436 | return error_mark_node; | |
3ab4693e | 1437 | expr = void_node; |
2e0e6579 | 1438 | } |
dab3247a | 1439 | else if (implicit != ICV_CAST && probe == expr && is_overloaded_fn (probe)) |
2056769e | 1440 | { |
1441 | /* Only warn when there is no &. */ | |
ebd21de4 | 1442 | if (complain & tf_warning) |
dab3247a | 1443 | switch (implicit) |
1444 | { | |
1445 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1446 | warning_at (loc, OPT_Waddress, |
1447 | "second operand of conditional expression " | |
1448 | "is a reference, not call, to function %qE", expr); | |
dab3247a | 1449 | break; |
1450 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1451 | warning_at (loc, OPT_Waddress, |
1452 | "third operand of conditional expression " | |
1453 | "is a reference, not call, to function %qE", expr); | |
dab3247a | 1454 | break; |
1455 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1456 | warning_at (loc, OPT_Waddress, |
1457 | "right operand of comma operator " | |
1458 | "is a reference, not call, to function %qE", expr); | |
dab3247a | 1459 | break; |
1460 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1461 | warning_at (loc, OPT_Waddress, |
1462 | "left operand of comma operator " | |
1463 | "is a reference, not call, to function %qE", expr); | |
dab3247a | 1464 | break; |
1465 | case ICV_STATEMENT: | |
61f69bc9 | 1466 | warning_at (loc, OPT_Waddress, |
1467 | "statement is a reference, not call, to function %qE", | |
1468 | expr); | |
dab3247a | 1469 | break; |
1470 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1471 | warning_at (loc, OPT_Waddress, |
1472 | "for increment expression " | |
1473 | "is a reference, not call, to function %qE", expr); | |
dab3247a | 1474 | break; |
1475 | default: | |
1476 | gcc_unreachable (); | |
1477 | } | |
1478 | ||
2056769e | 1479 | if (TREE_CODE (expr) == COMPONENT_REF) |
1480 | expr = TREE_OPERAND (expr, 0); | |
1481 | } | |
b1a8d4ce | 1482 | } |
9031d10b | 1483 | |
e3cfe3ce | 1484 | if (expr != error_mark_node && !VOID_TYPE_P (TREE_TYPE (expr))) |
b1a8d4ce | 1485 | { |
dab3247a | 1486 | if (implicit != ICV_CAST |
5e2a4133 | 1487 | && warn_unused_value |
1488 | && !TREE_NO_WARNING (expr) | |
1489 | && !processing_template_decl) | |
1fe46df1 | 1490 | { |
1491 | /* The middle end does not warn about expressions that have | |
1492 | been explicitly cast to void, so we must do so here. */ | |
ebd21de4 | 1493 | if (!TREE_SIDE_EFFECTS (expr)) { |
1494 | if (complain & tf_warning) | |
dab3247a | 1495 | switch (implicit) |
1496 | { | |
1497 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1498 | warning_at (loc, OPT_Wunused_value, |
1499 | "second operand of conditional expression " | |
1500 | "has no effect"); | |
dab3247a | 1501 | break; |
1502 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1503 | warning_at (loc, OPT_Wunused_value, |
1504 | "third operand of conditional expression " | |
1505 | "has no effect"); | |
dab3247a | 1506 | break; |
1507 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1508 | warning_at (loc, OPT_Wunused_value, |
1509 | "right operand of comma operator has no effect"); | |
dab3247a | 1510 | break; |
1511 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1512 | warning_at (loc, OPT_Wunused_value, |
1513 | "left operand of comma operator has no effect"); | |
dab3247a | 1514 | break; |
1515 | case ICV_STATEMENT: | |
61f69bc9 | 1516 | warning_at (loc, OPT_Wunused_value, |
1517 | "statement has no effect"); | |
dab3247a | 1518 | break; |
1519 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1520 | warning_at (loc, OPT_Wunused_value, |
1521 | "for increment expression has no effect"); | |
dab3247a | 1522 | break; |
1523 | default: | |
1524 | gcc_unreachable (); | |
1525 | } | |
ebd21de4 | 1526 | } |
9031d10b | 1527 | else |
1528 | { | |
1fe46df1 | 1529 | tree e; |
1530 | enum tree_code code; | |
607a5d68 | 1531 | enum tree_code_class tclass; |
9031d10b | 1532 | |
1fe46df1 | 1533 | e = expr; |
1534 | /* We might like to warn about (say) "(int) f()", as the | |
1535 | cast has no effect, but the compiler itself will | |
1536 | generate implicit conversions under some | |
324d8f2d | 1537 | circumstances. (For example a block copy will be |
1fe46df1 | 1538 | turned into a call to "__builtin_memcpy", with a |
1539 | conversion of the return value to an appropriate | |
1540 | type.) So, to avoid false positives, we strip | |
416ce344 | 1541 | conversions. Do not use STRIP_NOPs because it will |
1542 | not strip conversions to "void", as that is not a | |
1543 | mode-preserving conversion. */ | |
1544 | while (TREE_CODE (e) == NOP_EXPR) | |
1545 | e = TREE_OPERAND (e, 0); | |
1fe46df1 | 1546 | |
1547 | code = TREE_CODE (e); | |
607a5d68 | 1548 | tclass = TREE_CODE_CLASS (code); |
1549 | if ((tclass == tcc_comparison | |
1550 | || tclass == tcc_unary | |
1551 | || (tclass == tcc_binary | |
1fe46df1 | 1552 | && !(code == MODIFY_EXPR |
1553 | || code == INIT_EXPR | |
1554 | || code == PREDECREMENT_EXPR | |
1555 | || code == PREINCREMENT_EXPR | |
1556 | || code == POSTDECREMENT_EXPR | |
9372a89d | 1557 | || code == POSTINCREMENT_EXPR)) |
1558 | || code == VEC_PERM_EXPR | |
1559 | || code == VEC_COND_EXPR) | |
ebd21de4 | 1560 | && (complain & tf_warning)) |
61f69bc9 | 1561 | warning_at (loc, OPT_Wunused_value, "value computed is not used"); |
1fe46df1 | 1562 | } |
1563 | } | |
00fa9079 | 1564 | expr = build1 (CONVERT_EXPR, void_type_node, expr); |
b1a8d4ce | 1565 | } |
de5ad4cb | 1566 | if (! TREE_SIDE_EFFECTS (expr)) |
3ab4693e | 1567 | expr = void_node; |
b1a8d4ce | 1568 | return expr; |
1569 | } | |
1570 | ||
d81e00a4 | 1571 | /* Create an expression whose value is that of EXPR, |
1572 | converted to type TYPE. The TREE_TYPE of the value | |
1573 | is always TYPE. This function implements all reasonable | |
1574 | conversions; callers should filter out those that are | |
c4a8ac95 | 1575 | not permitted by the language being compiled. |
1576 | ||
1577 | Most of this routine is from build_reinterpret_cast. | |
1578 | ||
a17c2a3a | 1579 | The back end cannot call cp_convert (what was convert) because |
c4a8ac95 | 1580 | conversions to/from basetypes may involve memory references |
1581 | (vbases) and adding or subtracting small values (multiple | |
1582 | inheritance), but it calls convert from the constant folding code | |
e0aa5007 | 1583 | on subtrees of already built trees after it has ripped them apart. |
c4a8ac95 | 1584 | |
1585 | Also, if we ever support range variables, we'll probably also have to | |
1586 | do a little bit more work. */ | |
d81e00a4 | 1587 | |
1588 | tree | |
35771a9a | 1589 | convert (tree type, tree expr) |
d81e00a4 | 1590 | { |
c4a8ac95 | 1591 | tree intype; |
1592 | ||
1593 | if (type == error_mark_node || expr == error_mark_node) | |
1594 | return error_mark_node; | |
1595 | ||
c4a8ac95 | 1596 | intype = TREE_TYPE (expr); |
1597 | ||
6686e84d | 1598 | if (POINTER_TYPE_P (type) && POINTER_TYPE_P (intype)) |
d2c63826 | 1599 | return build_nop (type, expr); |
c4a8ac95 | 1600 | |
b981525c | 1601 | return ocp_convert (type, expr, CONV_BACKEND_CONVERT, |
c4698a21 | 1602 | LOOKUP_NORMAL|LOOKUP_NO_CONVERSION, |
1603 | tf_warning_or_error); | |
d81e00a4 | 1604 | } |
1605 | ||
c4a8ac95 | 1606 | /* Like cp_convert, except permit conversions to take place which |
471086d6 | 1607 | are not normally allowed due to access restrictions |
1608 | (such as conversion from sub-type to private super-type). */ | |
96624a9e | 1609 | |
471086d6 | 1610 | tree |
c4698a21 | 1611 | convert_force (tree type, tree expr, int convtype, tsubst_flags_t complain) |
471086d6 | 1612 | { |
cd16867a | 1613 | tree e = expr; |
1614 | enum tree_code code = TREE_CODE (type); | |
471086d6 | 1615 | |
1616 | if (code == REFERENCE_TYPE) | |
d2c63826 | 1617 | return convert_to_reference (type, e, CONV_C_CAST, 0, |
1618 | NULL_TREE, complain); | |
471086d6 | 1619 | |
1620 | if (code == POINTER_TYPE) | |
d2c63826 | 1621 | return convert_to_pointer_force (type, e, complain); |
471086d6 | 1622 | |
ac9386a0 | 1623 | /* From typeck.c convert_for_assignment */ |
c21c015b | 1624 | if (((TYPE_PTR_P (TREE_TYPE (e)) && TREE_CODE (e) == ADDR_EXPR |
471086d6 | 1625 | && TREE_CODE (TREE_TYPE (TREE_TYPE (e))) == METHOD_TYPE) |
ac9386a0 | 1626 | || integer_zerop (e) |
1627 | || TYPE_PTRMEMFUNC_P (TREE_TYPE (e))) | |
471086d6 | 1628 | && TYPE_PTRMEMFUNC_P (type)) |
cb02169c | 1629 | /* compatible pointer to member functions. */ |
1630 | return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), e, 1, | |
c4698a21 | 1631 | /*c_cast_p=*/1, complain); |
a74e8896 | 1632 | |
c4698a21 | 1633 | return ocp_convert (type, e, CONV_C_CAST|convtype, LOOKUP_NORMAL, complain); |
471086d6 | 1634 | } |
1635 | ||
471086d6 | 1636 | /* Convert an aggregate EXPR to type XTYPE. If a conversion |
1637 | exists, return the attempted conversion. This may | |
1638 | return ERROR_MARK_NODE if the conversion is not | |
1639 | allowed (references private members, etc). | |
1640 | If no conversion exists, NULL_TREE is returned. | |
1641 | ||
ce28ee2e | 1642 | FIXME: Ambiguity checking is wrong. Should choose one by the implicit |
1643 | object parameter, or by the second standard conversion sequence if | |
1644 | that doesn't do it. This will probably wait for an overloading rewrite. | |
1645 | (jason 8/9/95) */ | |
471086d6 | 1646 | |
ef9571e5 | 1647 | static tree |
8999978b | 1648 | build_type_conversion (tree xtype, tree expr) |
471086d6 | 1649 | { |
1650 | /* C++: check to see if we can convert this aggregate type | |
bcf789d7 | 1651 | into the required type. */ |
66bbeb85 | 1652 | return build_user_type_conversion (xtype, expr, LOOKUP_NORMAL, |
1653 | tf_warning_or_error); | |
471086d6 | 1654 | } |
1655 | ||
1e66592c | 1656 | /* Convert the given EXPR to one of a group of types suitable for use in an |
1657 | expression. DESIRES is a combination of various WANT_* flags (q.v.) | |
35771a9a | 1658 | which indicates which types are suitable. If COMPLAIN is true, complain |
1e66592c | 1659 | about ambiguity; otherwise, the caller will deal with it. */ |
471086d6 | 1660 | |
1e66592c | 1661 | tree |
35771a9a | 1662 | build_expr_type_conversion (int desires, tree expr, bool complain) |
471086d6 | 1663 | { |
1e66592c | 1664 | tree basetype = TREE_TYPE (expr); |
6a44e72e | 1665 | tree conv = NULL_TREE; |
bdd152ce | 1666 | tree winner = NULL_TREE; |
471086d6 | 1667 | |
d76863c8 | 1668 | if (null_node_p (expr) |
9031d10b | 1669 | && (desires & WANT_INT) |
954885ed | 1670 | && !(desires & WANT_NULL)) |
db30b351 | 1671 | { |
1672 | source_location loc = | |
1673 | expansion_point_location_if_in_system_header (input_location); | |
1674 | ||
1675 | warning_at (loc, OPT_Wconversion_null, | |
1676 | "converting NULL to non-pointer type"); | |
1677 | } | |
9031d10b | 1678 | |
3d411d73 | 1679 | if (basetype == error_mark_node) |
1680 | return error_mark_node; | |
1681 | ||
95397ff9 | 1682 | if (! MAYBE_CLASS_TYPE_P (basetype)) |
bdd152ce | 1683 | switch (TREE_CODE (basetype)) |
1684 | { | |
1685 | case INTEGER_TYPE: | |
954885ed | 1686 | if ((desires & WANT_NULL) && null_ptr_cst_p (expr)) |
bdd152ce | 1687 | return expr; |
e3533433 | 1688 | /* fall through. */ |
bdd152ce | 1689 | |
1690 | case BOOLEAN_TYPE: | |
1691 | return (desires & WANT_INT) ? expr : NULL_TREE; | |
1692 | case ENUMERAL_TYPE: | |
1693 | return (desires & WANT_ENUM) ? expr : NULL_TREE; | |
1694 | case REAL_TYPE: | |
1695 | return (desires & WANT_FLOAT) ? expr : NULL_TREE; | |
1696 | case POINTER_TYPE: | |
1697 | return (desires & WANT_POINTER) ? expr : NULL_TREE; | |
9031d10b | 1698 | |
bdd152ce | 1699 | case FUNCTION_TYPE: |
1700 | case ARRAY_TYPE: | |
4405c1ad | 1701 | return (desires & WANT_POINTER) ? decay_conversion (expr, |
1702 | tf_warning_or_error) | |
653e5405 | 1703 | : NULL_TREE; |
96ec9e30 | 1704 | |
64ec1ad6 | 1705 | case COMPLEX_TYPE: |
96ec9e30 | 1706 | case VECTOR_TYPE: |
64ec1ad6 | 1707 | if ((desires & WANT_VECTOR_OR_COMPLEX) == 0) |
96ec9e30 | 1708 | return NULL_TREE; |
1709 | switch (TREE_CODE (TREE_TYPE (basetype))) | |
1710 | { | |
1711 | case INTEGER_TYPE: | |
1712 | case BOOLEAN_TYPE: | |
1713 | return (desires & WANT_INT) ? expr : NULL_TREE; | |
1714 | case ENUMERAL_TYPE: | |
1715 | return (desires & WANT_ENUM) ? expr : NULL_TREE; | |
1716 | case REAL_TYPE: | |
1717 | return (desires & WANT_FLOAT) ? expr : NULL_TREE; | |
1718 | default: | |
1719 | return NULL_TREE; | |
1720 | } | |
1721 | ||
bdd152ce | 1722 | default: |
1723 | return NULL_TREE; | |
1724 | } | |
1725 | ||
1726 | /* The code for conversions from class type is currently only used for | |
1727 | delete expressions. Other expressions are handled by build_new_op. */ | |
a5f2d620 | 1728 | if (!complete_type_or_maybe_complain (basetype, expr, complain)) |
f8182e08 | 1729 | return error_mark_node; |
1730 | if (!TYPE_HAS_CONVERSION (basetype)) | |
bdd152ce | 1731 | return NULL_TREE; |
1732 | ||
9960d752 | 1733 | for (conv = lookup_conversions (basetype); conv; conv = TREE_CHAIN (conv)) |
bdd152ce | 1734 | { |
1735 | int win = 0; | |
1736 | tree candidate; | |
1737 | tree cand = TREE_VALUE (conv); | |
6767ca9a | 1738 | cand = OVL_FIRST (cand); |
bdd152ce | 1739 | |
1740 | if (winner && winner == cand) | |
1741 | continue; | |
1742 | ||
cf7aa2e5 | 1743 | if (DECL_NONCONVERTING_P (cand)) |
1744 | continue; | |
1745 | ||
ef4534a3 | 1746 | candidate = non_reference (TREE_TYPE (TREE_TYPE (cand))); |
bdd152ce | 1747 | |
1748 | switch (TREE_CODE (candidate)) | |
1749 | { | |
1750 | case BOOLEAN_TYPE: | |
1751 | case INTEGER_TYPE: | |
1752 | win = (desires & WANT_INT); break; | |
1753 | case ENUMERAL_TYPE: | |
1754 | win = (desires & WANT_ENUM); break; | |
1755 | case REAL_TYPE: | |
1756 | win = (desires & WANT_FLOAT); break; | |
1757 | case POINTER_TYPE: | |
1758 | win = (desires & WANT_POINTER); break; | |
1759 | ||
64ec1ad6 | 1760 | case COMPLEX_TYPE: |
96ec9e30 | 1761 | case VECTOR_TYPE: |
64ec1ad6 | 1762 | if ((desires & WANT_VECTOR_OR_COMPLEX) == 0) |
96ec9e30 | 1763 | break; |
1764 | switch (TREE_CODE (TREE_TYPE (candidate))) | |
1765 | { | |
1766 | case BOOLEAN_TYPE: | |
1767 | case INTEGER_TYPE: | |
1768 | win = (desires & WANT_INT); break; | |
1769 | case ENUMERAL_TYPE: | |
1770 | win = (desires & WANT_ENUM); break; | |
1771 | case REAL_TYPE: | |
1772 | win = (desires & WANT_FLOAT); break; | |
1773 | default: | |
1774 | break; | |
1775 | } | |
1776 | break; | |
1777 | ||
bdd152ce | 1778 | default: |
9c4c1195 | 1779 | /* A wildcard could be instantiated to match any desired |
1780 | type, but we can't deduce the template argument. */ | |
1781 | if (WILDCARD_TYPE_P (candidate)) | |
1782 | win = true; | |
bdd152ce | 1783 | break; |
1784 | } | |
1785 | ||
1786 | if (win) | |
1787 | { | |
9c4c1195 | 1788 | if (TREE_CODE (cand) == TEMPLATE_DECL) |
1789 | { | |
1790 | if (complain) | |
1791 | error ("default type conversion can't deduce template" | |
1792 | " argument for %qD", cand); | |
1793 | return error_mark_node; | |
1794 | } | |
1795 | ||
bdd152ce | 1796 | if (winner) |
1797 | { | |
609c541f | 1798 | tree winner_type |
1799 | = non_reference (TREE_TYPE (TREE_TYPE (winner))); | |
1800 | ||
1801 | if (!same_type_ignoring_top_level_qualifiers_p (winner_type, | |
1802 | candidate)) | |
bdd152ce | 1803 | { |
609c541f | 1804 | if (complain) |
1805 | { | |
1806 | error ("ambiguous default type conversion from %qT", | |
1807 | basetype); | |
392214f6 | 1808 | inform (input_location, |
1809 | " candidate conversions include %qD and %qD", | |
1810 | winner, cand); | |
609c541f | 1811 | } |
1812 | return error_mark_node; | |
bdd152ce | 1813 | } |
bdd152ce | 1814 | } |
609c541f | 1815 | |
1816 | winner = cand; | |
bdd152ce | 1817 | } |
1818 | } | |
1e66592c | 1819 | |
bdd152ce | 1820 | if (winner) |
1821 | { | |
ef4534a3 | 1822 | tree type = non_reference (TREE_TYPE (TREE_TYPE (winner))); |
66bbeb85 | 1823 | return build_user_type_conversion (type, expr, LOOKUP_NORMAL, |
1824 | tf_warning_or_error); | |
471086d6 | 1825 | } |
1e66592c | 1826 | |
985e9ee0 | 1827 | return NULL_TREE; |
471086d6 | 1828 | } |
bc3887cf | 1829 | |
96624a9e | 1830 | /* Implements integral promotion (4.1) and float->double promotion. */ |
1831 | ||
bc3887cf | 1832 | tree |
35771a9a | 1833 | type_promotes_to (tree type) |
bc3887cf | 1834 | { |
2b3c93a3 | 1835 | tree promoted_type; |
1836 | ||
ce28ee2e | 1837 | if (type == error_mark_node) |
1838 | return error_mark_node; | |
1839 | ||
bc3887cf | 1840 | type = TYPE_MAIN_VARIANT (type); |
bb0726a1 | 1841 | |
2b3c93a3 | 1842 | /* Check for promotions of target-defined types first. */ |
1843 | promoted_type = targetm.promoted_type (type); | |
1844 | if (promoted_type) | |
1845 | return promoted_type; | |
1846 | ||
bb0726a1 | 1847 | /* bool always promotes to int (not unsigned), even if it's the same |
1848 | size. */ | |
9e1a8234 | 1849 | if (TREE_CODE (type) == BOOLEAN_TYPE) |
bb0726a1 | 1850 | type = integer_type_node; |
1851 | ||
1852 | /* Normally convert enums to int, but convert wide enums to something | |
74b777e5 | 1853 | wider. Scoped enums don't promote, but pretend they do for backward |
1854 | ABI bug compatibility wrt varargs. */ | |
bb0726a1 | 1855 | else if (TREE_CODE (type) == ENUMERAL_TYPE |
924bbf02 | 1856 | || type == char16_type_node |
1857 | || type == char32_type_node | |
bb0726a1 | 1858 | || type == wchar_type_node) |
6c9497b1 | 1859 | { |
c042ba6f | 1860 | tree prom = type; |
1861 | ||
1862 | if (TREE_CODE (type) == ENUMERAL_TYPE) | |
1863 | { | |
1864 | prom = ENUM_UNDERLYING_TYPE (prom); | |
1865 | if (!ENUM_IS_SCOPED (type) | |
1866 | && ENUM_FIXED_UNDERLYING_TYPE_P (type)) | |
1867 | { | |
1868 | /* ISO C++17, 7.6/4. A prvalue of an unscoped enumeration type | |
1869 | whose underlying type is fixed (10.2) can be converted to a | |
1870 | prvalue of its underlying type. Moreover, if integral promotion | |
1871 | can be applied to its underlying type, a prvalue of an unscoped | |
1872 | enumeration type whose underlying type is fixed can also be | |
1873 | converted to a prvalue of the promoted underlying type. */ | |
1874 | return type_promotes_to (prom); | |
1875 | } | |
1876 | } | |
1877 | ||
6c9497b1 | 1878 | int precision = MAX (TYPE_PRECISION (type), |
1879 | TYPE_PRECISION (integer_type_node)); | |
771d21fa | 1880 | tree totype = c_common_type_for_size (precision, 0); |
74b777e5 | 1881 | if (TYPE_UNSIGNED (prom) |
1882 | && ! int_fits_type_p (TYPE_MAX_VALUE (prom), totype)) | |
1883 | prom = c_common_type_for_size (precision, 1); | |
1884 | else | |
1885 | prom = totype; | |
72fc0f64 | 1886 | if (SCOPED_ENUM_P (type)) |
74b777e5 | 1887 | { |
1888 | if (abi_version_crosses (6) | |
1889 | && TYPE_MODE (prom) != TYPE_MODE (type)) | |
1890 | warning (OPT_Wabi, "scoped enum %qT passed through ... as " | |
1891 | "%qT before -fabi-version=6, %qT after", | |
1892 | type, prom, ENUM_UNDERLYING_TYPE (type)); | |
1893 | if (!abi_version_at_least (6)) | |
1894 | type = prom; | |
1895 | } | |
6c9497b1 | 1896 | else |
74b777e5 | 1897 | type = prom; |
6c9497b1 | 1898 | } |
d7aeef06 | 1899 | else if (c_promoting_integer_type_p (type)) |
bc3887cf | 1900 | { |
d0acef9e | 1901 | /* Retain unsignedness if really not getting bigger. */ |
78a8ed03 | 1902 | if (TYPE_UNSIGNED (type) |
d0acef9e | 1903 | && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)) |
bc3887cf | 1904 | type = unsigned_type_node; |
1905 | else | |
1906 | type = integer_type_node; | |
1907 | } | |
1908 | else if (type == float_type_node) | |
1909 | type = double_type_node; | |
9031d10b | 1910 | |
a681799d | 1911 | return type; |
bc3887cf | 1912 | } |
668ae905 | 1913 | |
668ae905 | 1914 | /* The routines below this point are carefully written to conform to |
1915 | the standard. They use the same terminology, and follow the rules | |
1916 | closely. Although they are used only in pt.c at the moment, they | |
1917 | should presumably be used everywhere in the future. */ | |
1918 | ||
0a8a2108 | 1919 | /* True iff EXPR can be converted to TYPE via a qualification conversion. |
1920 | Callers should check for identical types before calling this function. */ | |
1921 | ||
1922 | bool | |
1923 | can_convert_qual (tree type, tree expr) | |
1924 | { | |
1925 | tree expr_type = TREE_TYPE (expr); | |
1926 | gcc_assert (!same_type_p (type, expr_type)); | |
1927 | ||
1928 | if (TYPE_PTR_P (type) && TYPE_PTR_P (expr_type)) | |
1929 | return comp_ptr_ttypes (TREE_TYPE (type), TREE_TYPE (expr_type)); | |
1930 | else if (TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (expr_type)) | |
1931 | return (same_type_p (TYPE_PTRMEM_CLASS_TYPE (type), | |
1932 | TYPE_PTRMEM_CLASS_TYPE (expr_type)) | |
1933 | && comp_ptr_ttypes (TYPE_PTRMEM_POINTED_TO_TYPE (type), | |
1934 | TYPE_PTRMEM_POINTED_TO_TYPE (expr_type))); | |
1935 | else | |
1936 | return false; | |
1937 | } | |
1938 | ||
1146f179 | 1939 | /* Attempt to perform qualification conversions on EXPR to convert it |
1940 | to TYPE. Return the resulting expression, or error_mark_node if | |
1941 | the conversion was impossible. */ | |
1942 | ||
9031d10b | 1943 | tree |
35771a9a | 1944 | perform_qualification_conversions (tree type, tree expr) |
668ae905 | 1945 | { |
1bc16cab | 1946 | tree expr_type; |
1947 | ||
1948 | expr_type = TREE_TYPE (expr); | |
1949 | ||
3b087710 | 1950 | if (same_type_p (type, expr_type)) |
1951 | return expr; | |
0a8a2108 | 1952 | else if (can_convert_qual (type, expr)) |
1bc16cab | 1953 | return build_nop (type, expr); |
1146f179 | 1954 | else |
1955 | return error_mark_node; | |
668ae905 | 1956 | } |
6d02e6b2 | 1957 | |
1958 | /* True iff T is a transaction-safe function type. */ | |
1959 | ||
1960 | bool | |
1961 | tx_safe_fn_type_p (tree t) | |
1962 | { | |
1963 | if (TREE_CODE (t) != FUNCTION_TYPE | |
1964 | && TREE_CODE (t) != METHOD_TYPE) | |
1965 | return false; | |
1966 | return !!lookup_attribute ("transaction_safe", TYPE_ATTRIBUTES (t)); | |
1967 | } | |
1968 | ||
1969 | /* Return the transaction-unsafe variant of transaction-safe function type | |
1970 | T. */ | |
1971 | ||
1972 | tree | |
1973 | tx_unsafe_fn_variant (tree t) | |
1974 | { | |
1975 | gcc_assert (tx_safe_fn_type_p (t)); | |
1976 | tree attrs = remove_attribute ("transaction_safe", | |
1977 | TYPE_ATTRIBUTES (t)); | |
1978 | return cp_build_type_attribute_variant (t, attrs); | |
1979 | } | |
1980 | ||
1981 | /* Return true iff FROM can convert to TO by a transaction-safety | |
1982 | conversion. */ | |
1983 | ||
2e9e9363 | 1984 | static bool |
6d02e6b2 | 1985 | can_convert_tx_safety (tree to, tree from) |
1986 | { | |
1987 | return (flag_tm && tx_safe_fn_type_p (from) | |
1988 | && same_type_p (to, tx_unsafe_fn_variant (from))); | |
1989 | } | |
2e9e9363 | 1990 | |
1991 | /* Return true iff FROM can convert to TO by dropping noexcept. */ | |
1992 | ||
1993 | static bool | |
1994 | noexcept_conv_p (tree to, tree from) | |
1995 | { | |
1996 | if (!flag_noexcept_type) | |
1997 | return false; | |
1998 | ||
1999 | tree t = non_reference (to); | |
2000 | tree f = from; | |
2001 | if (TYPE_PTRMEMFUNC_P (t) | |
2002 | && TYPE_PTRMEMFUNC_P (f)) | |
2003 | { | |
2004 | t = TYPE_PTRMEMFUNC_FN_TYPE (t); | |
2005 | f = TYPE_PTRMEMFUNC_FN_TYPE (f); | |
2006 | } | |
2007 | if (TREE_CODE (t) == POINTER_TYPE | |
2008 | && TREE_CODE (f) == POINTER_TYPE) | |
2009 | { | |
2010 | t = TREE_TYPE (t); | |
2011 | f = TREE_TYPE (f); | |
2012 | } | |
2013 | tree_code code = TREE_CODE (f); | |
2014 | if (TREE_CODE (t) != code) | |
2015 | return false; | |
2016 | if (code != FUNCTION_TYPE && code != METHOD_TYPE) | |
2017 | return false; | |
2018 | if (!type_throw_all_p (t) | |
2019 | || type_throw_all_p (f)) | |
2020 | return false; | |
2021 | tree v = build_exception_variant (f, NULL_TREE); | |
2022 | return same_type_p (t, v); | |
2023 | } | |
2024 | ||
2025 | /* Return true iff FROM can convert to TO by a function pointer conversion. */ | |
2026 | ||
2027 | bool | |
2028 | fnptr_conv_p (tree to, tree from) | |
2029 | { | |
2030 | tree t = non_reference (to); | |
2031 | tree f = from; | |
2032 | if (TYPE_PTRMEMFUNC_P (t) | |
2033 | && TYPE_PTRMEMFUNC_P (f)) | |
2034 | { | |
2035 | t = TYPE_PTRMEMFUNC_FN_TYPE (t); | |
2036 | f = TYPE_PTRMEMFUNC_FN_TYPE (f); | |
2037 | } | |
2038 | if (TREE_CODE (t) == POINTER_TYPE | |
2039 | && TREE_CODE (f) == POINTER_TYPE) | |
2040 | { | |
2041 | t = TREE_TYPE (t); | |
2042 | f = TREE_TYPE (f); | |
2043 | } | |
2044 | ||
2045 | return (noexcept_conv_p (t, f) | |
2046 | || can_convert_tx_safety (t, f)); | |
2047 | } | |
2048 | ||
2104a0fd | 2049 | /* Return FN with any NOP_EXPRs stripped that represent function pointer |
2050 | conversions or conversions to the same type. */ | |
2e9e9363 | 2051 | |
2052 | tree | |
2053 | strip_fnptr_conv (tree fn) | |
2054 | { | |
2055 | while (TREE_CODE (fn) == NOP_EXPR) | |
2056 | { | |
2057 | tree op = TREE_OPERAND (fn, 0); | |
2104a0fd | 2058 | tree ft = TREE_TYPE (fn); |
2059 | tree ot = TREE_TYPE (op); | |
2060 | if (same_type_p (ft, ot) | |
2061 | || fnptr_conv_p (ft, ot)) | |
2e9e9363 | 2062 | fn = op; |
2063 | else | |
2064 | break; | |
2065 | } | |
2066 | return fn; | |
2067 | } |