]>
Commit | Line | Data |
---|---|---|
471086d6 | 1 | /* Language-level data type conversion for GNU C++. |
aad93da1 | 2 | Copyright (C) 1987-2017 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 | |
b981525c | 242 | return convert_to_pointer_maybe_fold (type, expr, dofold); |
471086d6 | 243 | } |
244 | ||
cc4d0855 | 245 | if (type_unknown_p (expr)) |
c4698a21 | 246 | return instantiate_type (type, expr, complain); |
cc4d0855 | 247 | |
c4698a21 | 248 | if (complain & tf_error) |
4d1eda3a | 249 | error_at (loc, "cannot convert %qE from type %qH to type %qI", |
c4698a21 | 250 | expr, intype, type); |
471086d6 | 251 | return error_mark_node; |
252 | } | |
253 | ||
254 | /* Like convert, except permit conversions to take place which | |
255 | are not normally allowed due to access restrictions | |
256 | (such as conversion from sub-type to private super-type). */ | |
96624a9e | 257 | |
471086d6 | 258 | static tree |
c4698a21 | 259 | convert_to_pointer_force (tree type, tree expr, tsubst_flags_t complain) |
471086d6 | 260 | { |
cd16867a | 261 | tree intype = TREE_TYPE (expr); |
262 | enum tree_code form = TREE_CODE (intype); | |
9031d10b | 263 | |
471086d6 | 264 | if (form == POINTER_TYPE) |
265 | { | |
266 | intype = TYPE_MAIN_VARIANT (intype); | |
267 | ||
268 | if (TYPE_MAIN_VARIANT (type) != intype | |
269 | && TREE_CODE (TREE_TYPE (type)) == RECORD_TYPE | |
95397ff9 | 270 | && MAYBE_CLASS_TYPE_P (TREE_TYPE (type)) |
271 | && MAYBE_CLASS_TYPE_P (TREE_TYPE (intype)) | |
471086d6 | 272 | && TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE) |
273 | { | |
274 | enum tree_code code = PLUS_EXPR; | |
4a2680fc | 275 | tree binfo; |
276 | ||
277 | binfo = lookup_base (TREE_TYPE (intype), TREE_TYPE (type), | |
ae260dcc | 278 | ba_unique, NULL, complain); |
4a2680fc | 279 | if (!binfo) |
471086d6 | 280 | { |
4a2680fc | 281 | binfo = lookup_base (TREE_TYPE (type), TREE_TYPE (intype), |
ae260dcc | 282 | ba_unique, NULL, complain); |
4a2680fc | 283 | code = MINUS_EXPR; |
471086d6 | 284 | } |
4a2680fc | 285 | if (binfo == error_mark_node) |
286 | return error_mark_node; | |
287 | if (binfo) | |
471086d6 | 288 | { |
c4698a21 | 289 | expr = build_base_path (code, expr, binfo, 0, complain); |
653e5405 | 290 | if (expr == error_mark_node) |
291 | return error_mark_node; | |
c0af329c | 292 | /* Add any qualifier conversions. */ |
4a2680fc | 293 | if (!same_type_p (TREE_TYPE (TREE_TYPE (expr)), |
294 | TREE_TYPE (type))) | |
8999978b | 295 | expr = build_nop (type, expr); |
4a2680fc | 296 | return expr; |
471086d6 | 297 | } |
471086d6 | 298 | } |
471086d6 | 299 | } |
300 | ||
b981525c | 301 | return cp_convert_to_pointer (type, expr, /*fold*/false, complain); |
471086d6 | 302 | } |
303 | ||
304 | /* We are passing something to a function which requires a reference. | |
305 | The type we are interested in is in TYPE. The initial | |
306 | value we have to begin with is in ARG. | |
307 | ||
308 | FLAGS controls how we manage access checking. | |
ca106ab1 | 309 | DIRECT_BIND in FLAGS controls how any temporaries are generated. |
310 | If DIRECT_BIND is set, DECL is the reference we're binding to. */ | |
96624a9e | 311 | |
471086d6 | 312 | static tree |
c4698a21 | 313 | build_up_reference (tree type, tree arg, int flags, tree decl, |
314 | tsubst_flags_t complain) | |
471086d6 | 315 | { |
c76251c1 | 316 | tree rval; |
0543e7a9 | 317 | tree argtype = TREE_TYPE (arg); |
471086d6 | 318 | tree target_type = TREE_TYPE (type); |
471086d6 | 319 | |
b4df430b | 320 | gcc_assert (TREE_CODE (type) == REFERENCE_TYPE); |
471086d6 | 321 | |
18bede74 | 322 | if ((flags & DIRECT_BIND) && ! lvalue_p (arg)) |
471086d6 | 323 | { |
ca106ab1 | 324 | /* Create a new temporary variable. We can't just use a TARGET_EXPR |
325 | here because it needs to live as long as DECL. */ | |
c76251c1 | 326 | tree targ = arg; |
ca106ab1 | 327 | |
5ab1aaca | 328 | arg = make_temporary_var_for_ref_to_temp (decl, target_type); |
c23ebfdd | 329 | |
330 | /* Process the initializer for the declaration. */ | |
38281c46 | 331 | DECL_INITIAL (arg) = targ; |
d91303a6 | 332 | cp_finish_decl (arg, targ, /*init_const_expr_p=*/false, NULL_TREE, |
011310f7 | 333 | LOOKUP_ONLYCONVERTING|DIRECT_BIND); |
1ad432f2 | 334 | } |
049132bc | 335 | else if (!(flags & DIRECT_BIND) && ! obvalue_p (arg)) |
44189c16 | 336 | return get_target_expr_sfinae (arg, complain); |
1ad432f2 | 337 | |
ca106ab1 | 338 | /* If we had a way to wrap this up, and say, if we ever needed its |
b0df6589 | 339 | address, transform all occurrences of the register, into a memory |
340 | reference we could win better. */ | |
44189c16 | 341 | rval = cp_build_addr_expr (arg, complain); |
15e55420 | 342 | if (rval == error_mark_node) |
343 | return error_mark_node; | |
344 | ||
6686e84d | 345 | if ((flags & LOOKUP_PROTECT) |
346 | && TYPE_MAIN_VARIANT (argtype) != TYPE_MAIN_VARIANT (target_type) | |
95397ff9 | 347 | && MAYBE_CLASS_TYPE_P (argtype) |
348 | && MAYBE_CLASS_TYPE_P (target_type)) | |
6686e84d | 349 | { |
7e6960e0 | 350 | /* We go through lookup_base for the access control. */ |
ae260dcc | 351 | tree binfo = lookup_base (argtype, target_type, ba_check, |
352 | NULL, complain); | |
6686e84d | 353 | if (binfo == error_mark_node) |
354 | return error_mark_node; | |
355 | if (binfo == NULL_TREE) | |
356 | return error_not_base_type (target_type, argtype); | |
c4698a21 | 357 | rval = build_base_path (PLUS_EXPR, rval, binfo, 1, complain); |
6686e84d | 358 | } |
c76251c1 | 359 | else |
360 | rval | |
c4698a21 | 361 | = convert_to_pointer_force (build_pointer_type (target_type), |
362 | rval, complain); | |
8999978b | 363 | return build_nop (type, rval); |
471086d6 | 364 | } |
365 | ||
519ba62c | 366 | /* Subroutine of convert_to_reference. REFTYPE is the target reference type. |
367 | INTYPE is the original rvalue type and DECL is an optional _DECL node | |
368 | for diagnostics. | |
9031d10b | 369 | |
519ba62c | 370 | [dcl.init.ref] says that if an rvalue is used to |
371 | initialize a reference, then the reference must be to a | |
372 | non-volatile const type. */ | |
373 | ||
374 | static void | |
19b271a9 | 375 | diagnose_ref_binding (location_t loc, tree reftype, tree intype, tree decl) |
519ba62c | 376 | { |
377 | tree ttl = TREE_TYPE (reftype); | |
9031d10b | 378 | |
519ba62c | 379 | if (!CP_TYPE_CONST_NON_VOLATILE_P (ttl)) |
380 | { | |
381 | const char *msg; | |
382 | ||
383 | if (CP_TYPE_VOLATILE_P (ttl) && decl) | |
ca82e026 | 384 | msg = G_("initialization of volatile reference type %q#T from " |
385 | "rvalue of type %qT"); | |
519ba62c | 386 | else if (CP_TYPE_VOLATILE_P (ttl)) |
ca82e026 | 387 | msg = G_("conversion to volatile reference type %q#T " |
388 | "from rvalue of type %qT"); | |
519ba62c | 389 | else if (decl) |
ca82e026 | 390 | msg = G_("initialization of non-const reference type %q#T from " |
391 | "rvalue of type %qT"); | |
519ba62c | 392 | else |
ca82e026 | 393 | msg = G_("conversion to non-const reference type %q#T from " |
394 | "rvalue of type %qT"); | |
519ba62c | 395 | |
61f69bc9 | 396 | permerror (loc, msg, reftype, intype); |
519ba62c | 397 | } |
398 | } | |
399 | ||
471086d6 | 400 | /* For C++: Only need to do one-level references, but cannot |
401 | get tripped up on signed/unsigned differences. | |
402 | ||
d81e00a4 | 403 | DECL is either NULL_TREE or the _DECL node for a reference that is being |
404 | initialized. It can be error_mark_node if we don't know the _DECL but | |
405 | we know it's an initialization. */ | |
471086d6 | 406 | |
471086d6 | 407 | tree |
35771a9a | 408 | convert_to_reference (tree reftype, tree expr, int convtype, |
c4698a21 | 409 | int flags, tree decl, tsubst_flags_t complain) |
471086d6 | 410 | { |
cd16867a | 411 | tree type = TYPE_MAIN_VARIANT (TREE_TYPE (reftype)); |
412 | tree intype; | |
471086d6 | 413 | tree rval = NULL_TREE; |
1a3f833b | 414 | tree rval_as_conversion = NULL_TREE; |
1bc16cab | 415 | bool can_convert_intype_to_type; |
3df42822 | 416 | location_t loc = EXPR_LOC_OR_LOC (expr, input_location); |
1a3f833b | 417 | |
9031d10b | 418 | if (TREE_CODE (type) == FUNCTION_TYPE |
d32df6a6 | 419 | && TREE_TYPE (expr) == unknown_type_node) |
66bbeb85 | 420 | expr = instantiate_type (type, expr, complain); |
0a3b29ad | 421 | |
422 | if (expr == error_mark_node) | |
423 | return error_mark_node; | |
424 | ||
425 | intype = TREE_TYPE (expr); | |
cc4d0855 | 426 | |
b4df430b | 427 | gcc_assert (TREE_CODE (intype) != REFERENCE_TYPE); |
ab12ed55 | 428 | gcc_assert (TREE_CODE (reftype) == REFERENCE_TYPE); |
471086d6 | 429 | |
471086d6 | 430 | intype = TYPE_MAIN_VARIANT (intype); |
431 | ||
b657f346 | 432 | can_convert_intype_to_type = can_convert_standard (type, intype, complain); |
66bbeb85 | 433 | |
1bc16cab | 434 | if (!can_convert_intype_to_type |
95397ff9 | 435 | && (convtype & CONV_IMPLICIT) && MAYBE_CLASS_TYPE_P (intype) |
1a3f833b | 436 | && ! (flags & LOOKUP_NO_CONVERSION)) |
437 | { | |
438 | /* Look for a user-defined conversion to lvalue that we can use. */ | |
439 | ||
0a4be248 | 440 | rval_as_conversion |
8999978b | 441 | = build_type_conversion (reftype, expr); |
1a3f833b | 442 | |
443 | if (rval_as_conversion && rval_as_conversion != error_mark_node | |
18bede74 | 444 | && lvalue_p (rval_as_conversion)) |
1a3f833b | 445 | { |
446 | expr = rval_as_conversion; | |
447 | rval_as_conversion = NULL_TREE; | |
448 | intype = type; | |
1bc16cab | 449 | can_convert_intype_to_type = 1; |
1a3f833b | 450 | } |
451 | } | |
452 | ||
b657f346 | 453 | if (((convtype & CONV_STATIC) |
454 | && can_convert_standard (intype, type, complain)) | |
1bc16cab | 455 | || ((convtype & CONV_IMPLICIT) && can_convert_intype_to_type)) |
471086d6 | 456 | { |
c4698a21 | 457 | { |
458 | tree ttl = TREE_TYPE (reftype); | |
459 | tree ttr = lvalue_type (expr); | |
471086d6 | 460 | |
19b271a9 | 461 | if ((complain & tf_error) |
18bede74 | 462 | && ! lvalue_p (expr)) |
19b271a9 | 463 | diagnose_ref_binding (loc, reftype, intype, decl); |
9031d10b | 464 | |
c4698a21 | 465 | if (! (convtype & CONV_CONST) |
466 | && !at_least_as_qualified_p (ttl, ttr)) | |
467 | { | |
468 | if (complain & tf_error) | |
4d1eda3a | 469 | permerror (loc, "conversion from %qH to %qI discards qualifiers", |
c4698a21 | 470 | ttr, reftype); |
471 | else | |
472 | return error_mark_node; | |
473 | } | |
474 | } | |
0543e7a9 | 475 | |
c4698a21 | 476 | return build_up_reference (reftype, expr, flags, decl, complain); |
471086d6 | 477 | } |
049132bc | 478 | else if ((convtype & CONV_REINTERPRET) && obvalue_p (expr)) |
0543e7a9 | 479 | { |
480 | /* When casting an lvalue to a reference type, just convert into | |
481 | a pointer to the new type and deference it. This is allowed | |
e581f478 | 482 | by San Diego WP section 5.2.9 paragraph 12, though perhaps it |
0543e7a9 | 483 | should be done directly (jason). (int &)ri ---> *(int*)&ri */ |
e581f478 | 484 | |
3748625f | 485 | /* B* bp; A& ar = (A&)bp; is valid, but it's probably not what they |
653e5405 | 486 | meant. */ |
c4698a21 | 487 | if ((complain & tf_warning) |
c21c015b | 488 | && TYPE_PTR_P (intype) |
a09db423 | 489 | && (comptypes (TREE_TYPE (intype), type, |
490 | COMPARE_BASE | COMPARE_DERIVED))) | |
61f69bc9 | 491 | warning_at (loc, 0, "casting %qT to %qT does not dereference pointer", |
492 | intype, reftype); | |
9031d10b | 493 | |
c4698a21 | 494 | rval = cp_build_addr_expr (expr, complain); |
0543e7a9 | 495 | if (rval != error_mark_node) |
985e9ee0 | 496 | rval = convert_force (build_pointer_type (TREE_TYPE (reftype)), |
c4698a21 | 497 | rval, 0, complain); |
0543e7a9 | 498 | if (rval != error_mark_node) |
b0722fac | 499 | rval = build1 (NOP_EXPR, reftype, rval); |
0543e7a9 | 500 | } |
0a4be248 | 501 | else |
860740a7 | 502 | { |
503 | rval = convert_for_initialization (NULL_TREE, type, expr, flags, | |
c4698a21 | 504 | ICR_CONVERTING, 0, 0, complain); |
a66fe4cb | 505 | if (rval == NULL_TREE || rval == error_mark_node) |
506 | return rval; | |
19b271a9 | 507 | if (complain & tf_error) |
508 | diagnose_ref_binding (loc, reftype, intype, decl); | |
c4698a21 | 509 | rval = build_up_reference (reftype, rval, flags, decl, complain); |
860740a7 | 510 | } |
471086d6 | 511 | |
512 | if (rval) | |
513 | { | |
96624a9e | 514 | /* If we found a way to convert earlier, then use it. */ |
471086d6 | 515 | return rval; |
516 | } | |
517 | ||
c4698a21 | 518 | if (complain & tf_error) |
4d1eda3a | 519 | error_at (loc, "cannot convert type %qH to type %qI", intype, reftype); |
b248d3f7 | 520 | |
471086d6 | 521 | return error_mark_node; |
522 | } | |
523 | ||
524 | /* We are using a reference VAL for its value. Bash that reference all the | |
96624a9e | 525 | way down to its lowest form. */ |
526 | ||
471086d6 | 527 | tree |
35771a9a | 528 | convert_from_reference (tree val) |
471086d6 | 529 | { |
73bdcca2 | 530 | if (TREE_TYPE (val) |
531 | && TREE_CODE (TREE_TYPE (val)) == REFERENCE_TYPE) | |
729f89ff | 532 | { |
2fb61329 | 533 | tree t = TREE_TYPE (TREE_TYPE (val)); |
729f89ff | 534 | tree ref = build1 (INDIRECT_REF, t, val); |
9031d10b | 535 | |
3d37a176 | 536 | mark_exp_read (val); |
729f89ff | 537 | /* We *must* set TREE_READONLY when dereferencing a pointer to const, |
538 | so that we get the proper error message if the result is used | |
539 | to assign to. Also, &* is supposed to be a no-op. */ | |
540 | TREE_READONLY (ref) = CP_TYPE_CONST_P (t); | |
541 | TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t); | |
542 | TREE_SIDE_EFFECTS (ref) | |
543 | = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (val)); | |
729f89ff | 544 | val = ref; |
545 | } | |
9031d10b | 546 | |
471086d6 | 547 | return val; |
548 | } | |
e5dab226 | 549 | |
550 | /* Really perform an lvalue-to-rvalue conversion, including copying an | |
551 | argument of class type into a temporary. */ | |
552 | ||
553 | tree | |
9e505437 | 554 | force_rvalue (tree expr, tsubst_flags_t complain) |
e5dab226 | 555 | { |
9e505437 | 556 | tree type = TREE_TYPE (expr); |
557 | if (MAYBE_CLASS_TYPE_P (type) && TREE_CODE (expr) != TARGET_EXPR) | |
558 | { | |
f1f41a6c | 559 | vec<tree, va_gc> *args = make_tree_vector_single (expr); |
9e505437 | 560 | expr = build_special_member_call (NULL_TREE, complete_ctor_identifier, |
561 | &args, type, LOOKUP_NORMAL, complain); | |
562 | release_tree_vector (args); | |
563 | expr = build_cplus_new (type, expr, complain); | |
564 | } | |
e5dab226 | 565 | else |
4405c1ad | 566 | expr = decay_conversion (expr, complain); |
e5dab226 | 567 | |
568 | return expr; | |
569 | } | |
f5220369 | 570 | |
471086d6 | 571 | \f |
a1f05651 | 572 | /* If EXPR and ORIG are INTEGER_CSTs, return a version of EXPR that has |
573 | TREE_OVERFLOW set only if it is set in ORIG. Otherwise, return EXPR | |
574 | unchanged. */ | |
575 | ||
576 | static tree | |
577 | ignore_overflows (tree expr, tree orig) | |
578 | { | |
579 | if (TREE_CODE (expr) == INTEGER_CST | |
580 | && TREE_CODE (orig) == INTEGER_CST | |
581 | && TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig)) | |
582 | { | |
583 | gcc_assert (!TREE_OVERFLOW (orig)); | |
584 | /* Ensure constant sharing. */ | |
e3d0f65c | 585 | expr = wide_int_to_tree (TREE_TYPE (expr), wi::to_wide (expr)); |
a1f05651 | 586 | } |
587 | return expr; | |
588 | } | |
589 | ||
590 | /* Fold away simple conversions, but make sure TREE_OVERFLOW is set | |
591 | properly. */ | |
f5220369 | 592 | |
593 | tree | |
594 | cp_fold_convert (tree type, tree expr) | |
595 | { | |
fe565588 | 596 | tree conv; |
597 | if (TREE_TYPE (expr) == type) | |
598 | conv = expr; | |
599 | else if (TREE_CODE (expr) == PTRMEM_CST) | |
600 | { | |
601 | /* Avoid wrapping a PTRMEM_CST in NOP_EXPR. */ | |
602 | conv = copy_node (expr); | |
603 | TREE_TYPE (conv) = type; | |
604 | } | |
605 | else | |
606 | { | |
607 | conv = fold_convert (type, expr); | |
608 | conv = ignore_overflows (conv, expr); | |
609 | } | |
a1f05651 | 610 | return conv; |
f5220369 | 611 | } |
612 | ||
c4a8ac95 | 613 | /* C++ conversions, preference to static cast conversions. */ |
614 | ||
615 | tree | |
c4698a21 | 616 | cp_convert (tree type, tree expr, tsubst_flags_t complain) |
c4a8ac95 | 617 | { |
c4698a21 | 618 | return ocp_convert (type, expr, CONV_OLD_CONVERT, LOOKUP_NORMAL, complain); |
c4a8ac95 | 619 | } |
620 | ||
59dd8856 | 621 | /* C++ equivalent of convert_and_check but using cp_convert as the |
622 | conversion function. | |
623 | ||
624 | Convert EXPR to TYPE, warning about conversion problems with constants. | |
625 | Invoke this function on every expression that is converted implicitly, | |
626 | i.e. because of language rules and not because of an explicit cast. */ | |
627 | ||
628 | tree | |
c4698a21 | 629 | cp_convert_and_check (tree type, tree expr, tsubst_flags_t complain) |
59dd8856 | 630 | { |
631 | tree result; | |
632 | ||
633 | if (TREE_TYPE (expr) == type) | |
634 | return expr; | |
d2c63826 | 635 | if (expr == error_mark_node) |
636 | return expr; | |
c4698a21 | 637 | result = cp_convert (type, expr, complain); |
59dd8856 | 638 | |
c4698a21 | 639 | if ((complain & tf_warning) |
65615944 | 640 | && c_inhibit_evaluation_warnings == 0) |
641 | { | |
d2c63826 | 642 | tree folded = cp_fully_fold (expr); |
643 | tree folded_result; | |
644 | if (folded == expr) | |
645 | folded_result = result; | |
646 | else | |
647 | { | |
648 | /* Avoid bogus -Wparentheses warnings. */ | |
93a735ed | 649 | warning_sentinel w (warn_parentheses); |
bed03df1 | 650 | warning_sentinel c (warn_int_in_bool_context); |
d2c63826 | 651 | folded_result = cp_convert (type, folded, tf_none); |
652 | } | |
653 | folded_result = fold_simple (folded_result); | |
654 | if (!TREE_OVERFLOW_P (folded) | |
65615944 | 655 | && folded_result != error_mark_node) |
3d27a0fa | 656 | warnings_for_convert_and_check (EXPR_LOC_OR_LOC (expr, input_location), |
657 | type, folded, folded_result); | |
65615944 | 658 | } |
59dd8856 | 659 | |
660 | return result; | |
661 | } | |
662 | ||
b248d3f7 | 663 | /* Conversion... |
664 | ||
665 | FLAGS indicates how we should behave. */ | |
666 | ||
471086d6 | 667 | tree |
c4698a21 | 668 | ocp_convert (tree type, tree expr, int convtype, int flags, |
669 | tsubst_flags_t complain) | |
471086d6 | 670 | { |
cd16867a | 671 | tree e = expr; |
672 | enum tree_code code = TREE_CODE (type); | |
7a979707 | 673 | const char *invalid_conv_diag; |
2b3c93a3 | 674 | tree e1; |
3df42822 | 675 | location_t loc = EXPR_LOC_OR_LOC (expr, input_location); |
b981525c | 676 | bool dofold = (convtype & CONV_FOLD); |
471086d6 | 677 | |
1bc16cab | 678 | if (error_operand_p (e) || type == error_mark_node) |
471086d6 | 679 | return error_mark_node; |
d81e00a4 | 680 | |
5b592939 | 681 | complete_type (type); |
682 | complete_type (TREE_TYPE (expr)); | |
683 | ||
7a979707 | 684 | if ((invalid_conv_diag |
685 | = targetm.invalid_conversion (TREE_TYPE (expr), type))) | |
686 | { | |
c4698a21 | 687 | if (complain & tf_error) |
688 | error (invalid_conv_diag); | |
7a979707 | 689 | return error_mark_node; |
690 | } | |
691 | ||
ce984e5e | 692 | /* FIXME remove when moving to c_fully_fold model. */ |
0a7452a8 | 693 | if (!CLASS_TYPE_P (type)) |
694 | e = scalar_constant_value (e); | |
7a00f939 | 695 | if (error_operand_p (e)) |
696 | return error_mark_node; | |
7745052b | 697 | |
c821ae1a | 698 | if (MAYBE_CLASS_TYPE_P (type) && (convtype & CONV_FORCE_TEMP)) |
ceab25e5 | 699 | /* We need a new temporary; don't take this shortcut. */; |
930e8175 | 700 | else if (same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (e))) |
ca23ec64 | 701 | { |
daf9ff67 | 702 | if (same_type_p (type, TREE_TYPE (e))) |
ca23ec64 | 703 | /* The call to fold will not always remove the NOP_EXPR as |
704 | might be expected, since if one of the types is a typedef; | |
755edffd | 705 | the comparison in fold is just equality of pointers, not a |
a09db423 | 706 | call to comptypes. We don't call fold in this case because |
f699c174 | 707 | that can result in infinite recursion; fold will call |
708 | convert, which will call ocp_convert, etc. */ | |
709 | return e; | |
372e0e29 | 710 | /* For complex data types, we need to perform componentwise |
653e5405 | 711 | conversion. */ |
372e0e29 | 712 | else if (TREE_CODE (type) == COMPLEX_TYPE) |
b981525c | 713 | return convert_to_complex_maybe_fold (type, e, dofold); |
76249021 | 714 | else if (VECTOR_TYPE_P (type)) |
d2c63826 | 715 | return convert_to_vector (type, e); |
bdb2219e | 716 | else if (TREE_CODE (e) == TARGET_EXPR) |
717 | { | |
718 | /* Don't build a NOP_EXPR of class type. Instead, change the | |
930e8175 | 719 | type of the temporary. */ |
bdb2219e | 720 | TREE_TYPE (e) = TREE_TYPE (TARGET_EXPR_SLOT (e)) = type; |
721 | return e; | |
722 | } | |
ca23ec64 | 723 | else |
092b1d6f | 724 | { |
725 | /* We shouldn't be treating objects of ADDRESSABLE type as | |
726 | rvalues. */ | |
727 | gcc_assert (!TREE_ADDRESSABLE (type)); | |
d2c63826 | 728 | return build_nop (type, e); |
092b1d6f | 729 | } |
ca23ec64 | 730 | } |
731 | ||
2b3c93a3 | 732 | e1 = targetm.convert_to_type (type, e); |
733 | if (e1) | |
734 | return e1; | |
735 | ||
d81e00a4 | 736 | if (code == VOID_TYPE && (convtype & CONV_STATIC)) |
95b2ac55 | 737 | { |
c4698a21 | 738 | e = convert_to_void (e, ICV_CAST, complain); |
aeef2be5 | 739 | return e; |
95b2ac55 | 740 | } |
d81e00a4 | 741 | |
bb0726a1 | 742 | if (INTEGRAL_CODE_P (code)) |
471086d6 | 743 | { |
617abf06 | 744 | tree intype = TREE_TYPE (e); |
a1f05651 | 745 | tree converted; |
384590d4 | 746 | |
747 | if (TREE_CODE (type) == ENUMERAL_TYPE) | |
748 | { | |
749 | /* enum = enum, enum = int, enum = float, (enum)pointer are all | |
750 | errors. */ | |
751 | if (((INTEGRAL_OR_ENUMERATION_TYPE_P (intype) | |
653e5405 | 752 | || TREE_CODE (intype) == REAL_TYPE) |
b312a686 | 753 | && ! (convtype & CONV_STATIC)) |
c21c015b | 754 | || TYPE_PTR_P (intype)) |
384590d4 | 755 | { |
c4698a21 | 756 | if (complain & tf_error) |
61f69bc9 | 757 | permerror (loc, "conversion from %q#T to %q#T", intype, type); |
c4698a21 | 758 | else |
384590d4 | 759 | return error_mark_node; |
760 | } | |
761 | ||
762 | /* [expr.static.cast] | |
763 | ||
764 | 8. A value of integral or enumeration type can be explicitly | |
765 | converted to an enumeration type. The value is unchanged if | |
766 | the original value is within the range of the enumeration | |
767 | values. Otherwise, the resulting enumeration value is | |
768 | unspecified. */ | |
c4698a21 | 769 | if ((complain & tf_warning) |
c28ddc97 | 770 | && TREE_CODE (e) == INTEGER_CST |
0116c9f8 | 771 | && ENUM_UNDERLYING_TYPE (type) |
c28ddc97 | 772 | && !int_fits_type_p (e, ENUM_UNDERLYING_TYPE (type))) |
61f69bc9 | 773 | warning_at (loc, OPT_Wconversion, |
774 | "the result of the conversion is unspecified because " | |
775 | "%qE is outside the range of type %qT", | |
776 | expr, type); | |
471086d6 | 777 | } |
95397ff9 | 778 | if (MAYBE_CLASS_TYPE_P (intype)) |
471086d6 | 779 | { |
780 | tree rval; | |
8999978b | 781 | rval = build_type_conversion (type, e); |
6495357a | 782 | if (rval) |
783 | return rval; | |
c4698a21 | 784 | if (complain & tf_error) |
61f69bc9 | 785 | error_at (loc, "%q#T used where a %qT was expected", intype, type); |
471086d6 | 786 | return error_mark_node; |
787 | } | |
bb0726a1 | 788 | if (code == BOOLEAN_TYPE) |
f8913d47 | 789 | { |
c21c015b | 790 | if (VOID_TYPE_P (intype)) |
61f69bc9 | 791 | { |
c4698a21 | 792 | if (complain & tf_error) |
793 | error_at (loc, | |
794 | "could not convert %qE from %<void%> to %<bool%>", | |
795 | expr); | |
61f69bc9 | 796 | return error_mark_node; |
797 | } | |
798 | ||
f8913d47 | 799 | /* We can't implicitly convert a scoped enum to bool, so convert |
800 | to the underlying type first. */ | |
801 | if (SCOPED_ENUM_P (intype) && (convtype & CONV_STATIC)) | |
172fff7b | 802 | e = build_nop (ENUM_UNDERLYING_TYPE (intype), e); |
493196c0 | 803 | if (complain & tf_warning) |
804 | return cp_truthvalue_conversion (e); | |
805 | else | |
806 | { | |
807 | /* Prevent bogus -Wint-in-bool-context warnings coming | |
808 | from c_common_truthvalue_conversion down the line. */ | |
809 | warning_sentinel w (warn_int_in_bool_context); | |
810 | return cp_truthvalue_conversion (e); | |
811 | } | |
f8913d47 | 812 | } |
ce871053 | 813 | |
b981525c | 814 | converted = convert_to_integer_maybe_fold (type, e, dofold); |
a1f05651 | 815 | |
816 | /* Ignore any integer overflow caused by the conversion. */ | |
817 | return ignore_overflows (converted, e); | |
471086d6 | 818 | } |
c7ca48ea | 819 | if (NULLPTR_TYPE_P (type) && e && null_ptr_cst_p (e)) |
49858f84 | 820 | { |
821 | if (complain & tf_warning) | |
822 | maybe_warn_zero_as_null_pointer_constant (e, loc); | |
823 | return nullptr_node; | |
824 | } | |
05765a91 | 825 | if (POINTER_TYPE_P (type) || TYPE_PTRMEM_P (type)) |
b981525c | 826 | return cp_convert_to_pointer (type, e, dofold, complain); |
684b9d79 | 827 | if (code == VECTOR_TYPE) |
c37ff371 | 828 | { |
829 | tree in_vtype = TREE_TYPE (e); | |
95397ff9 | 830 | if (MAYBE_CLASS_TYPE_P (in_vtype)) |
c37ff371 | 831 | { |
832 | tree ret_val; | |
833 | ret_val = build_type_conversion (type, e); | |
653e5405 | 834 | if (ret_val) |
835 | return ret_val; | |
c4698a21 | 836 | if (complain & tf_error) |
837 | error_at (loc, "%q#T used where a %qT was expected", | |
838 | in_vtype, type); | |
653e5405 | 839 | return error_mark_node; |
c37ff371 | 840 | } |
d2c63826 | 841 | return convert_to_vector (type, e); |
c37ff371 | 842 | } |
c4a8ac95 | 843 | if (code == REAL_TYPE || code == COMPLEX_TYPE) |
471086d6 | 844 | { |
95397ff9 | 845 | if (MAYBE_CLASS_TYPE_P (TREE_TYPE (e))) |
471086d6 | 846 | { |
847 | tree rval; | |
8999978b | 848 | rval = build_type_conversion (type, e); |
471086d6 | 849 | if (rval) |
850 | return rval; | |
c4698a21 | 851 | else if (complain & tf_error) |
852 | error_at (loc, | |
853 | "%q#T used where a floating point value was expected", | |
854 | TREE_TYPE (e)); | |
471086d6 | 855 | } |
c4a8ac95 | 856 | if (code == REAL_TYPE) |
b981525c | 857 | return convert_to_real_maybe_fold (type, e, dofold); |
c4a8ac95 | 858 | else if (code == COMPLEX_TYPE) |
b981525c | 859 | return convert_to_complex_maybe_fold (type, e, dofold); |
471086d6 | 860 | } |
861 | ||
862 | /* New C++ semantics: since assignment is now based on | |
863 | memberwise copying, if the rhs type is derived from the | |
864 | lhs type, then we may still do a conversion. */ | |
95397ff9 | 865 | if (RECORD_OR_UNION_CODE_P (code)) |
471086d6 | 866 | { |
867 | tree dtype = TREE_TYPE (e); | |
c25194fd | 868 | tree ctor = NULL_TREE; |
471086d6 | 869 | |
471086d6 | 870 | dtype = TYPE_MAIN_VARIANT (dtype); |
871 | ||
471086d6 | 872 | /* Conversion between aggregate types. New C++ semantics allow |
873 | objects of derived type to be cast to objects of base type. | |
874 | Old semantics only allowed this between pointers. | |
875 | ||
876 | There may be some ambiguity between using a constructor | |
877 | vs. using a type conversion operator when both apply. */ | |
878 | ||
0a4be248 | 879 | ctor = e; |
860740a7 | 880 | |
44189c16 | 881 | if (abstract_virtuals_error_sfinae (NULL_TREE, type, complain)) |
8c18e707 | 882 | return error_mark_node; |
6cbb4197 | 883 | |
f82f1250 | 884 | if (BRACE_ENCLOSED_INITIALIZER_P (ctor)) |
c4698a21 | 885 | ctor = perform_implicit_conversion (type, ctor, complain); |
f82f1250 | 886 | else if ((flags & LOOKUP_ONLYCONVERTING) |
887 | && ! (CLASS_TYPE_P (dtype) && DERIVED_FROM_P (type, dtype))) | |
fce73460 | 888 | /* For copy-initialization, first we create a temp of the proper type |
889 | with a user-defined conversion sequence, then we direct-initialize | |
890 | the target with the temp (see [dcl.init]). */ | |
c4698a21 | 891 | ctor = build_user_type_conversion (type, ctor, flags, complain); |
3eb89cd8 | 892 | else |
f352a3fb | 893 | { |
f1f41a6c | 894 | vec<tree, va_gc> *ctor_vec = make_tree_vector_single (ctor); |
f352a3fb | 895 | ctor = build_special_member_call (NULL_TREE, |
896 | complete_ctor_identifier, | |
897 | &ctor_vec, | |
c4698a21 | 898 | type, flags, complain); |
f352a3fb | 899 | release_tree_vector (ctor_vec); |
900 | } | |
0a4be248 | 901 | if (ctor) |
c4698a21 | 902 | return build_cplus_new (type, ctor, complain); |
471086d6 | 903 | } |
904 | ||
c4698a21 | 905 | if (complain & tf_error) |
a7cc1549 | 906 | { |
907 | /* If the conversion failed and expr was an invalid use of pointer to | |
908 | member function, try to report a meaningful error. */ | |
5c874cd3 | 909 | if (invalid_nonstatic_memfn_p (loc, expr, complain)) |
a7cc1549 | 910 | /* We displayed the error message. */; |
911 | else | |
4d1eda3a | 912 | error_at (loc, "conversion from %qH to non-scalar type %qI requested", |
61f69bc9 | 913 | TREE_TYPE (expr), type); |
a7cc1549 | 914 | } |
471086d6 | 915 | return error_mark_node; |
916 | } | |
917 | ||
3ae3cb42 | 918 | /* If CALL is a call, return the callee; otherwise null. */ |
919 | ||
920 | tree | |
921 | cp_get_callee (tree call) | |
922 | { | |
923 | if (call == NULL_TREE) | |
924 | return call; | |
925 | else if (TREE_CODE (call) == CALL_EXPR) | |
926 | return CALL_EXPR_FN (call); | |
927 | else if (TREE_CODE (call) == AGGR_INIT_EXPR) | |
928 | return AGGR_INIT_EXPR_FN (call); | |
929 | return NULL_TREE; | |
930 | } | |
931 | ||
ddd2a3d4 | 932 | /* FN is the callee of a CALL_EXPR or AGGR_INIT_EXPR; return the FUNCTION_DECL |
933 | if we can. */ | |
934 | ||
935 | tree | |
936 | cp_get_fndecl_from_callee (tree fn) | |
937 | { | |
938 | if (fn == NULL_TREE) | |
939 | return fn; | |
940 | if (TREE_CODE (fn) == FUNCTION_DECL) | |
941 | return fn; | |
942 | tree type = TREE_TYPE (fn); | |
943 | if (type == unknown_type_node) | |
944 | return NULL_TREE; | |
945 | gcc_assert (POINTER_TYPE_P (type)); | |
946 | fn = maybe_constant_init (fn); | |
947 | STRIP_NOPS (fn); | |
948 | if (TREE_CODE (fn) == ADDR_EXPR) | |
949 | { | |
950 | fn = TREE_OPERAND (fn, 0); | |
951 | if (TREE_CODE (fn) == FUNCTION_DECL) | |
952 | return fn; | |
953 | } | |
954 | return NULL_TREE; | |
955 | } | |
956 | ||
957 | /* Like get_callee_fndecl, but handles AGGR_INIT_EXPR as well and uses the | |
958 | constexpr machinery. */ | |
959 | ||
960 | tree | |
961 | cp_get_callee_fndecl (tree call) | |
962 | { | |
963 | return cp_get_fndecl_from_callee (cp_get_callee (call)); | |
964 | } | |
965 | ||
966 | /* Subroutine of convert_to_void. Warn if we're discarding something with | |
967 | attribute [[nodiscard]]. */ | |
968 | ||
969 | static void | |
970 | maybe_warn_nodiscard (tree expr, impl_conv_void implicit) | |
971 | { | |
972 | tree call = expr; | |
973 | if (TREE_CODE (expr) == TARGET_EXPR) | |
974 | call = TARGET_EXPR_INITIAL (expr); | |
975 | location_t loc = EXPR_LOC_OR_LOC (call, input_location); | |
976 | tree callee = cp_get_callee (call); | |
977 | if (!callee) | |
978 | return; | |
979 | ||
980 | tree type = TREE_TYPE (callee); | |
981 | if (TYPE_PTRMEMFUNC_P (type)) | |
982 | type = TYPE_PTRMEMFUNC_FN_TYPE (type); | |
983 | if (POINTER_TYPE_P (type)) | |
984 | type = TREE_TYPE (type); | |
985 | ||
986 | tree rettype = TREE_TYPE (type); | |
987 | tree fn = cp_get_fndecl_from_callee (callee); | |
988 | if (implicit != ICV_CAST && fn | |
989 | && lookup_attribute ("nodiscard", DECL_ATTRIBUTES (fn))) | |
990 | { | |
991 | if (warning_at (loc, OPT_Wunused_result, | |
992 | "ignoring return value of %qD, " | |
993 | "declared with attribute nodiscard", fn)) | |
994 | inform (DECL_SOURCE_LOCATION (fn), "declared here"); | |
995 | } | |
996 | else if (implicit != ICV_CAST | |
997 | && lookup_attribute ("nodiscard", TYPE_ATTRIBUTES (rettype))) | |
998 | { | |
999 | if (warning_at (loc, OPT_Wunused_result, | |
1000 | "ignoring returned value of type %qT, " | |
1001 | "declared with attribute nodiscard", rettype)) | |
1002 | { | |
1003 | if (fn) | |
1004 | inform (DECL_SOURCE_LOCATION (fn), | |
1005 | "in call to %qD, declared here", fn); | |
1006 | inform (DECL_SOURCE_LOCATION (TYPE_NAME (rettype)), | |
1007 | "%qT declared here", rettype); | |
1008 | } | |
1009 | } | |
1010 | else if (TREE_CODE (expr) == TARGET_EXPR | |
1011 | && lookup_attribute ("warn_unused_result", TYPE_ATTRIBUTES (type))) | |
1012 | { | |
1013 | /* The TARGET_EXPR confuses do_warn_unused_result into thinking that the | |
1014 | result is used, so handle that case here. */ | |
1015 | if (fn) | |
1016 | { | |
1017 | if (warning_at (loc, OPT_Wunused_result, | |
1018 | "ignoring return value of %qD, " | |
1019 | "declared with attribute warn_unused_result", | |
1020 | fn)) | |
1021 | inform (DECL_SOURCE_LOCATION (fn), "declared here"); | |
1022 | } | |
1023 | else | |
1024 | warning_at (loc, OPT_Wunused_result, | |
1025 | "ignoring return value of function " | |
1026 | "declared with attribute warn_unused_result"); | |
1027 | } | |
1028 | } | |
1029 | ||
b1a8d4ce | 1030 | /* When an expression is used in a void context, its value is discarded and |
1031 | no lvalue-rvalue and similar conversions happen [expr.static.cast/4, | |
1032 | stmt.expr/1, expr.comma/1]. This permits dereferencing an incomplete type | |
1033 | in a void context. The C++ standard does not define what an `access' to an | |
63eff20d | 1034 | object is, but there is reason to believe that it is the lvalue to rvalue |
b1a8d4ce | 1035 | conversion -- if it were not, `*&*p = 1' would violate [expr]/4 in that it |
1036 | accesses `*p' not to calculate the value to be stored. But, dcl.type.cv/8 | |
1037 | indicates that volatile semantics should be the same between C and C++ | |
1038 | where ever possible. C leaves it implementation defined as to what | |
1039 | constitutes an access to a volatile. So, we interpret `*vp' as a read of | |
1040 | the volatile object `vp' points to, unless that is an incomplete type. For | |
1041 | volatile references we do not do this interpretation, because that would | |
1042 | make it impossible to ignore the reference return value from functions. We | |
1043 | issue warnings in the confusing cases. | |
9031d10b | 1044 | |
dab3247a | 1045 | The IMPLICIT is ICV_CAST when the user is explicitly converting an expression |
1046 | to void via a cast. If an expression is being implicitly converted, IMPLICIT | |
1047 | indicates the context of the implicit conversion. */ | |
b1a8d4ce | 1048 | |
1049 | tree | |
dab3247a | 1050 | convert_to_void (tree expr, impl_conv_void implicit, tsubst_flags_t complain) |
b1a8d4ce | 1051 | { |
3df42822 | 1052 | location_t loc = EXPR_LOC_OR_LOC (expr, input_location); |
61f69bc9 | 1053 | |
9031d10b | 1054 | if (expr == error_mark_node |
3d411d73 | 1055 | || TREE_TYPE (expr) == error_mark_node) |
1056 | return error_mark_node; | |
b2af2a93 | 1057 | |
dab3247a | 1058 | if (implicit == ICV_CAST) |
f94341bb | 1059 | mark_exp_read (expr); |
1060 | else | |
1061 | { | |
1062 | tree exprv = expr; | |
1063 | ||
1064 | while (TREE_CODE (exprv) == COMPOUND_EXPR) | |
1065 | exprv = TREE_OPERAND (exprv, 1); | |
0388391d | 1066 | if (DECL_P (exprv) |
1067 | || handled_component_p (exprv) | |
86ccc124 | 1068 | || INDIRECT_REF_P (exprv)) |
f94341bb | 1069 | /* Expr is not being 'used' here, otherwise we whould have |
1070 | called mark_{rl}value_use use here, which would have in turn | |
1071 | called mark_exp_read. Rather, we call mark_exp_read directly | |
1072 | to avoid some warnings when | |
1073 | -Wunused-but-set-{variable,parameter} is in effect. */ | |
1074 | mark_exp_read (exprv); | |
1075 | } | |
b2af2a93 | 1076 | |
b1a8d4ce | 1077 | if (!TREE_TYPE (expr)) |
1078 | return expr; | |
5c874cd3 | 1079 | if (invalid_nonstatic_memfn_p (loc, expr, complain)) |
334f6ce1 | 1080 | return error_mark_node; |
ed36f1cf | 1081 | if (TREE_CODE (expr) == PSEUDO_DTOR_EXPR) |
1082 | { | |
ebd21de4 | 1083 | if (complain & tf_error) |
61f69bc9 | 1084 | error_at (loc, "pseudo-destructor is not called"); |
ed36f1cf | 1085 | return error_mark_node; |
1086 | } | |
e3cfe3ce | 1087 | if (VOID_TYPE_P (TREE_TYPE (expr))) |
b1a8d4ce | 1088 | return expr; |
1089 | switch (TREE_CODE (expr)) | |
1090 | { | |
1091 | case COND_EXPR: | |
1092 | { | |
653e5405 | 1093 | /* The two parts of a cond expr might be separate lvalues. */ |
1094 | tree op1 = TREE_OPERAND (expr,1); | |
1095 | tree op2 = TREE_OPERAND (expr,2); | |
527facbb | 1096 | bool side_effects = ((op1 && TREE_SIDE_EFFECTS (op1)) |
1097 | || TREE_SIDE_EFFECTS (op2)); | |
dab3247a | 1098 | tree new_op1, new_op2; |
527facbb | 1099 | new_op1 = NULL_TREE; |
dab3247a | 1100 | if (implicit != ICV_CAST && !side_effects) |
1101 | { | |
527facbb | 1102 | if (op1) |
1103 | new_op1 = convert_to_void (op1, ICV_SECOND_OF_COND, complain); | |
dab3247a | 1104 | new_op2 = convert_to_void (op2, ICV_THIRD_OF_COND, complain); |
1105 | } | |
1106 | else | |
1107 | { | |
527facbb | 1108 | if (op1) |
1109 | new_op1 = convert_to_void (op1, ICV_CAST, complain); | |
dab3247a | 1110 | new_op2 = convert_to_void (op2, ICV_CAST, complain); |
1111 | } | |
9031d10b | 1112 | |
527facbb | 1113 | expr = build3 (COND_EXPR, TREE_TYPE (new_op2), |
831d52a2 | 1114 | TREE_OPERAND (expr, 0), new_op1, new_op2); |
653e5405 | 1115 | break; |
b1a8d4ce | 1116 | } |
9031d10b | 1117 | |
b1a8d4ce | 1118 | case COMPOUND_EXPR: |
1119 | { | |
653e5405 | 1120 | /* The second part of a compound expr contains the value. */ |
1121 | tree op1 = TREE_OPERAND (expr,1); | |
dab3247a | 1122 | tree new_op1; |
1123 | if (implicit != ICV_CAST && !TREE_NO_WARNING (expr)) | |
1124 | new_op1 = convert_to_void (op1, ICV_RIGHT_OF_COMMA, complain); | |
1125 | else | |
1126 | new_op1 = convert_to_void (op1, ICV_CAST, complain); | |
9031d10b | 1127 | |
653e5405 | 1128 | if (new_op1 != op1) |
e907a2e9 | 1129 | { |
831d52a2 | 1130 | tree t = build2 (COMPOUND_EXPR, TREE_TYPE (new_op1), |
1131 | TREE_OPERAND (expr, 0), new_op1); | |
e907a2e9 | 1132 | expr = t; |
1133 | } | |
1134 | ||
653e5405 | 1135 | break; |
b1a8d4ce | 1136 | } |
9031d10b | 1137 | |
b1a8d4ce | 1138 | case NON_LVALUE_EXPR: |
1139 | case NOP_EXPR: | |
c0af329c | 1140 | /* These have already decayed to rvalue. */ |
b1a8d4ce | 1141 | break; |
9031d10b | 1142 | |
331bc0ad | 1143 | case CALL_EXPR: /* We have a special meaning for volatile void fn(). */ |
ddd2a3d4 | 1144 | maybe_warn_nodiscard (expr, implicit); |
b1a8d4ce | 1145 | break; |
9031d10b | 1146 | |
b1a8d4ce | 1147 | case INDIRECT_REF: |
1148 | { | |
653e5405 | 1149 | tree type = TREE_TYPE (expr); |
1150 | int is_reference = TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) | |
1151 | == REFERENCE_TYPE; | |
1152 | int is_volatile = TYPE_VOLATILE (type); | |
1153 | int is_complete = COMPLETE_TYPE_P (complete_type (type)); | |
1154 | ||
dc02da7f | 1155 | /* Can't load the value if we don't know the type. */ |
653e5405 | 1156 | if (is_volatile && !is_complete) |
ebd21de4 | 1157 | { |
1158 | if (complain & tf_warning) | |
dab3247a | 1159 | switch (implicit) |
1160 | { | |
1161 | case ICV_CAST: | |
61f69bc9 | 1162 | warning_at (loc, 0, "conversion to void will not access " |
dab3247a | 1163 | "object of incomplete type %qT", type); |
1164 | break; | |
1165 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1166 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1167 | "incomplete type %qT in second operand " |
1168 | "of conditional expression", type); | |
1169 | break; | |
1170 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1171 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1172 | "incomplete type %qT in third operand " |
1173 | "of conditional expression", type); | |
1174 | break; | |
1175 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1176 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1177 | "incomplete type %qT in right operand of " |
1178 | "comma operator", type); | |
1179 | break; | |
1180 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1181 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1182 | "incomplete type %qT in left operand of " |
1183 | "comma operator", type); | |
1184 | break; | |
1185 | case ICV_STATEMENT: | |
61f69bc9 | 1186 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1187 | "incomplete type %qT in statement", type); |
1188 | break; | |
1189 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1190 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1191 | "incomplete type %qT in for increment " |
1192 | "expression", type); | |
1193 | break; | |
1194 | default: | |
1195 | gcc_unreachable (); | |
1196 | } | |
ebd21de4 | 1197 | } |
dc02da7f | 1198 | /* Don't load the value if this is an implicit dereference, or if |
1199 | the type needs to be handled by ctors/dtors. */ | |
dab3247a | 1200 | else if (is_volatile && is_reference) |
ebd21de4 | 1201 | { |
1202 | if (complain & tf_warning) | |
dab3247a | 1203 | switch (implicit) |
1204 | { | |
1205 | case ICV_CAST: | |
61f69bc9 | 1206 | warning_at (loc, 0, "conversion to void will not access " |
dab3247a | 1207 | "object of type %qT", type); |
1208 | break; | |
1209 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1210 | warning_at (loc, 0, "implicit dereference will not access " |
1211 | "object of type %qT in second operand of " | |
dab3247a | 1212 | "conditional expression", type); |
1213 | break; | |
1214 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1215 | warning_at (loc, 0, "implicit dereference will not access " |
1216 | "object of type %qT in third operand of " | |
dab3247a | 1217 | "conditional expression", type); |
1218 | break; | |
1219 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1220 | warning_at (loc, 0, "implicit dereference will not access " |
1221 | "object of type %qT in right operand of " | |
dab3247a | 1222 | "comma operator", type); |
1223 | break; | |
1224 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1225 | warning_at (loc, 0, "implicit dereference will not access " |
1226 | "object of type %qT in left operand of comma " | |
1227 | "operator", type); | |
dab3247a | 1228 | break; |
1229 | case ICV_STATEMENT: | |
61f69bc9 | 1230 | warning_at (loc, 0, "implicit dereference will not access " |
1231 | "object of type %qT in statement", type); | |
dab3247a | 1232 | break; |
1233 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1234 | warning_at (loc, 0, "implicit dereference will not access " |
1235 | "object of type %qT in for increment expression", | |
1236 | type); | |
dab3247a | 1237 | break; |
1238 | default: | |
1239 | gcc_unreachable (); | |
1240 | } | |
ebd21de4 | 1241 | } |
dab3247a | 1242 | else if (is_volatile && TREE_ADDRESSABLE (type)) |
1243 | { | |
1244 | if (complain & tf_warning) | |
1245 | switch (implicit) | |
1246 | { | |
1247 | case ICV_CAST: | |
61f69bc9 | 1248 | warning_at (loc, 0, "conversion to void will not access " |
dab3247a | 1249 | "object of non-trivially-copyable type %qT", |
61f69bc9 | 1250 | type); |
dab3247a | 1251 | break; |
1252 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1253 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1254 | "non-trivially-copyable type %qT in second " |
1255 | "operand of conditional expression", type); | |
1256 | break; | |
1257 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1258 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1259 | "non-trivially-copyable type %qT in third " |
1260 | "operand of conditional expression", type); | |
1261 | break; | |
1262 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1263 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1264 | "non-trivially-copyable type %qT in right " |
1265 | "operand of comma operator", type); | |
1266 | break; | |
1267 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1268 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1269 | "non-trivially-copyable type %qT in left " |
1270 | "operand of comma operator", type); | |
1271 | break; | |
1272 | case ICV_STATEMENT: | |
61f69bc9 | 1273 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1274 | "non-trivially-copyable type %qT in statement", |
61f69bc9 | 1275 | type); |
dab3247a | 1276 | break; |
1277 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1278 | warning_at (loc, 0, "indirection will not access object of " |
dab3247a | 1279 | "non-trivially-copyable type %qT in for " |
1280 | "increment expression", type); | |
1281 | break; | |
1282 | default: | |
1283 | gcc_unreachable (); | |
1284 | } | |
1285 | } | |
dc02da7f | 1286 | if (is_reference || !is_volatile || !is_complete || TREE_ADDRESSABLE (type)) |
a4d4030b | 1287 | { |
1288 | /* Emit a warning (if enabled) when the "effect-less" INDIRECT_REF | |
1289 | operation is stripped off. Note that we don't warn about | |
1290 | - an expression with TREE_NO_WARNING set. (For an example of | |
1291 | such expressions, see build_over_call in call.c.) | |
1292 | - automatic dereferencing of references, since the user cannot | |
3d177e8c | 1293 | control it. (See also warn_if_unused_value() in c-common.c.) */ |
a4d4030b | 1294 | if (warn_unused_value |
dab3247a | 1295 | && implicit != ICV_CAST |
a4d4030b | 1296 | && (complain & tf_warning) |
1297 | && !TREE_NO_WARNING (expr) | |
1298 | && !is_reference) | |
61f69bc9 | 1299 | warning_at (loc, OPT_Wunused_value, "value computed is not used"); |
a4d4030b | 1300 | expr = TREE_OPERAND (expr, 0); |
409bb09c | 1301 | if (TREE_CODE (expr) == CALL_EXPR) |
1302 | maybe_warn_nodiscard (expr, implicit); | |
a4d4030b | 1303 | } |
653e5405 | 1304 | |
1305 | break; | |
b1a8d4ce | 1306 | } |
9031d10b | 1307 | |
b1a8d4ce | 1308 | case VAR_DECL: |
1309 | { | |
653e5405 | 1310 | /* External variables might be incomplete. */ |
1311 | tree type = TREE_TYPE (expr); | |
1312 | int is_complete = COMPLETE_TYPE_P (complete_type (type)); | |
1313 | ||
ebd21de4 | 1314 | if (TYPE_VOLATILE (type) && !is_complete && (complain & tf_warning)) |
dab3247a | 1315 | switch (implicit) |
1316 | { | |
1317 | case ICV_CAST: | |
61f69bc9 | 1318 | warning_at (loc, 0, "conversion to void will not access " |
dab3247a | 1319 | "object %qE of incomplete type %qT", expr, type); |
1320 | break; | |
1321 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1322 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1323 | "not be accessed in second operand of " | |
dab3247a | 1324 | "conditional expression", expr, type); |
1325 | break; | |
1326 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1327 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1328 | "not be accessed in third operand of " | |
dab3247a | 1329 | "conditional expression", expr, type); |
1330 | break; | |
1331 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1332 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1333 | "not be accessed in right operand of comma operator", | |
1334 | expr, type); | |
dab3247a | 1335 | break; |
1336 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1337 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1338 | "not be accessed in left operand of comma operator", | |
1339 | expr, type); | |
dab3247a | 1340 | break; |
1341 | case ICV_STATEMENT: | |
61f69bc9 | 1342 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1343 | "not be accessed in statement", expr, type); | |
dab3247a | 1344 | break; |
1345 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1346 | warning_at (loc, 0, "variable %qE of incomplete type %qT will " |
1347 | "not be accessed in for increment expression", | |
1348 | expr, type); | |
dab3247a | 1349 | break; |
1350 | default: | |
1351 | gcc_unreachable (); | |
1352 | } | |
1353 | ||
653e5405 | 1354 | break; |
b1a8d4ce | 1355 | } |
d9f88785 | 1356 | |
25b3017b | 1357 | case TARGET_EXPR: |
1358 | /* Don't bother with the temporary object returned from a function if | |
1fe75cf2 | 1359 | we don't use it, don't need to destroy it, and won't abort in |
1360 | assign_temp. We'll still | |
25b3017b | 1361 | allocate space for it in expand_call or declare_return_variable, |
1362 | but we don't need to track it through all the tree phases. */ | |
67bb1301 | 1363 | if (TARGET_EXPR_IMPLICIT_P (expr) |
1fe75cf2 | 1364 | && !TREE_ADDRESSABLE (TREE_TYPE (expr))) |
25b3017b | 1365 | { |
1366 | tree init = TARGET_EXPR_INITIAL (expr); | |
1367 | if (TREE_CODE (init) == AGGR_INIT_EXPR | |
1368 | && !AGGR_INIT_VIA_CTOR_P (init)) | |
1369 | { | |
c2f47e15 | 1370 | tree fn = AGGR_INIT_EXPR_FN (init); |
389dd41b | 1371 | expr = build_call_array_loc (input_location, |
ddd2a3d4 | 1372 | TREE_TYPE (TREE_TYPE |
1373 | (TREE_TYPE (fn))), | |
389dd41b | 1374 | fn, |
1375 | aggr_init_expr_nargs (init), | |
1376 | AGGR_INIT_EXPR_ARGP (init)); | |
25b3017b | 1377 | } |
1378 | } | |
ddd2a3d4 | 1379 | maybe_warn_nodiscard (expr, implicit); |
25b3017b | 1380 | break; |
1381 | ||
b1a8d4ce | 1382 | default:; |
1383 | } | |
703eb775 | 1384 | expr = resolve_nondeduced_context (expr, complain); |
b1a8d4ce | 1385 | { |
1386 | tree probe = expr; | |
9031d10b | 1387 | |
b1a8d4ce | 1388 | if (TREE_CODE (probe) == ADDR_EXPR) |
1389 | probe = TREE_OPERAND (expr, 0); | |
2e0e6579 | 1390 | if (type_unknown_p (probe)) |
1391 | { | |
1392 | /* [over.over] enumerates the places where we can take the address | |
1393 | of an overloaded function, and this is not one of them. */ | |
ebd21de4 | 1394 | if (complain & tf_error) |
dab3247a | 1395 | switch (implicit) |
1396 | { | |
1397 | case ICV_CAST: | |
61f69bc9 | 1398 | error_at (loc, "conversion to void " |
1399 | "cannot resolve address of overloaded function"); | |
dab3247a | 1400 | break; |
1401 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1402 | error_at (loc, "second operand of conditional expression " |
1403 | "cannot resolve address of overloaded function"); | |
dab3247a | 1404 | break; |
1405 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1406 | error_at (loc, "third operand of conditional expression " |
1407 | "cannot resolve address of overloaded function"); | |
dab3247a | 1408 | break; |
1409 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1410 | error_at (loc, "right operand of comma operator " |
1411 | "cannot resolve address of overloaded function"); | |
dab3247a | 1412 | break; |
1413 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1414 | error_at (loc, "left operand of comma operator " |
1415 | "cannot resolve address of overloaded function"); | |
dab3247a | 1416 | break; |
1417 | case ICV_STATEMENT: | |
61f69bc9 | 1418 | error_at (loc, "statement " |
1419 | "cannot resolve address of overloaded function"); | |
dab3247a | 1420 | break; |
1421 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1422 | error_at (loc, "for increment expression " |
1423 | "cannot resolve address of overloaded function"); | |
dab3247a | 1424 | break; |
1425 | } | |
ebd21de4 | 1426 | else |
1427 | return error_mark_node; | |
3ab4693e | 1428 | expr = void_node; |
2e0e6579 | 1429 | } |
dab3247a | 1430 | else if (implicit != ICV_CAST && probe == expr && is_overloaded_fn (probe)) |
2056769e | 1431 | { |
1432 | /* Only warn when there is no &. */ | |
ebd21de4 | 1433 | if (complain & tf_warning) |
dab3247a | 1434 | switch (implicit) |
1435 | { | |
1436 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1437 | warning_at (loc, OPT_Waddress, |
1438 | "second operand of conditional expression " | |
1439 | "is a reference, not call, to function %qE", expr); | |
dab3247a | 1440 | break; |
1441 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1442 | warning_at (loc, OPT_Waddress, |
1443 | "third operand of conditional expression " | |
1444 | "is a reference, not call, to function %qE", expr); | |
dab3247a | 1445 | break; |
1446 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1447 | warning_at (loc, OPT_Waddress, |
1448 | "right operand of comma operator " | |
1449 | "is a reference, not call, to function %qE", expr); | |
dab3247a | 1450 | break; |
1451 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1452 | warning_at (loc, OPT_Waddress, |
1453 | "left operand of comma operator " | |
1454 | "is a reference, not call, to function %qE", expr); | |
dab3247a | 1455 | break; |
1456 | case ICV_STATEMENT: | |
61f69bc9 | 1457 | warning_at (loc, OPT_Waddress, |
1458 | "statement is a reference, not call, to function %qE", | |
1459 | expr); | |
dab3247a | 1460 | break; |
1461 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1462 | warning_at (loc, OPT_Waddress, |
1463 | "for increment expression " | |
1464 | "is a reference, not call, to function %qE", expr); | |
dab3247a | 1465 | break; |
1466 | default: | |
1467 | gcc_unreachable (); | |
1468 | } | |
1469 | ||
2056769e | 1470 | if (TREE_CODE (expr) == COMPONENT_REF) |
1471 | expr = TREE_OPERAND (expr, 0); | |
1472 | } | |
b1a8d4ce | 1473 | } |
9031d10b | 1474 | |
e3cfe3ce | 1475 | if (expr != error_mark_node && !VOID_TYPE_P (TREE_TYPE (expr))) |
b1a8d4ce | 1476 | { |
dab3247a | 1477 | if (implicit != ICV_CAST |
5e2a4133 | 1478 | && warn_unused_value |
1479 | && !TREE_NO_WARNING (expr) | |
1480 | && !processing_template_decl) | |
1fe46df1 | 1481 | { |
1482 | /* The middle end does not warn about expressions that have | |
1483 | been explicitly cast to void, so we must do so here. */ | |
ebd21de4 | 1484 | if (!TREE_SIDE_EFFECTS (expr)) { |
1485 | if (complain & tf_warning) | |
dab3247a | 1486 | switch (implicit) |
1487 | { | |
1488 | case ICV_SECOND_OF_COND: | |
61f69bc9 | 1489 | warning_at (loc, OPT_Wunused_value, |
1490 | "second operand of conditional expression " | |
1491 | "has no effect"); | |
dab3247a | 1492 | break; |
1493 | case ICV_THIRD_OF_COND: | |
61f69bc9 | 1494 | warning_at (loc, OPT_Wunused_value, |
1495 | "third operand of conditional expression " | |
1496 | "has no effect"); | |
dab3247a | 1497 | break; |
1498 | case ICV_RIGHT_OF_COMMA: | |
61f69bc9 | 1499 | warning_at (loc, OPT_Wunused_value, |
1500 | "right operand of comma operator has no effect"); | |
dab3247a | 1501 | break; |
1502 | case ICV_LEFT_OF_COMMA: | |
61f69bc9 | 1503 | warning_at (loc, OPT_Wunused_value, |
1504 | "left operand of comma operator has no effect"); | |
dab3247a | 1505 | break; |
1506 | case ICV_STATEMENT: | |
61f69bc9 | 1507 | warning_at (loc, OPT_Wunused_value, |
1508 | "statement has no effect"); | |
dab3247a | 1509 | break; |
1510 | case ICV_THIRD_IN_FOR: | |
61f69bc9 | 1511 | warning_at (loc, OPT_Wunused_value, |
1512 | "for increment expression has no effect"); | |
dab3247a | 1513 | break; |
1514 | default: | |
1515 | gcc_unreachable (); | |
1516 | } | |
ebd21de4 | 1517 | } |
9031d10b | 1518 | else |
1519 | { | |
1fe46df1 | 1520 | tree e; |
1521 | enum tree_code code; | |
607a5d68 | 1522 | enum tree_code_class tclass; |
9031d10b | 1523 | |
1fe46df1 | 1524 | e = expr; |
1525 | /* We might like to warn about (say) "(int) f()", as the | |
1526 | cast has no effect, but the compiler itself will | |
1527 | generate implicit conversions under some | |
324d8f2d | 1528 | circumstances. (For example a block copy will be |
1fe46df1 | 1529 | turned into a call to "__builtin_memcpy", with a |
1530 | conversion of the return value to an appropriate | |
1531 | type.) So, to avoid false positives, we strip | |
416ce344 | 1532 | conversions. Do not use STRIP_NOPs because it will |
1533 | not strip conversions to "void", as that is not a | |
1534 | mode-preserving conversion. */ | |
1535 | while (TREE_CODE (e) == NOP_EXPR) | |
1536 | e = TREE_OPERAND (e, 0); | |
1fe46df1 | 1537 | |
1538 | code = TREE_CODE (e); | |
607a5d68 | 1539 | tclass = TREE_CODE_CLASS (code); |
1540 | if ((tclass == tcc_comparison | |
1541 | || tclass == tcc_unary | |
1542 | || (tclass == tcc_binary | |
1fe46df1 | 1543 | && !(code == MODIFY_EXPR |
1544 | || code == INIT_EXPR | |
1545 | || code == PREDECREMENT_EXPR | |
1546 | || code == PREINCREMENT_EXPR | |
1547 | || code == POSTDECREMENT_EXPR | |
9372a89d | 1548 | || code == POSTINCREMENT_EXPR)) |
1549 | || code == VEC_PERM_EXPR | |
1550 | || code == VEC_COND_EXPR) | |
ebd21de4 | 1551 | && (complain & tf_warning)) |
61f69bc9 | 1552 | warning_at (loc, OPT_Wunused_value, "value computed is not used"); |
1fe46df1 | 1553 | } |
1554 | } | |
00fa9079 | 1555 | expr = build1 (CONVERT_EXPR, void_type_node, expr); |
b1a8d4ce | 1556 | } |
de5ad4cb | 1557 | if (! TREE_SIDE_EFFECTS (expr)) |
3ab4693e | 1558 | expr = void_node; |
b1a8d4ce | 1559 | return expr; |
1560 | } | |
1561 | ||
d81e00a4 | 1562 | /* Create an expression whose value is that of EXPR, |
1563 | converted to type TYPE. The TREE_TYPE of the value | |
1564 | is always TYPE. This function implements all reasonable | |
1565 | conversions; callers should filter out those that are | |
c4a8ac95 | 1566 | not permitted by the language being compiled. |
1567 | ||
1568 | Most of this routine is from build_reinterpret_cast. | |
1569 | ||
a17c2a3a | 1570 | The back end cannot call cp_convert (what was convert) because |
c4a8ac95 | 1571 | conversions to/from basetypes may involve memory references |
1572 | (vbases) and adding or subtracting small values (multiple | |
1573 | inheritance), but it calls convert from the constant folding code | |
e0aa5007 | 1574 | on subtrees of already built trees after it has ripped them apart. |
c4a8ac95 | 1575 | |
1576 | Also, if we ever support range variables, we'll probably also have to | |
1577 | do a little bit more work. */ | |
d81e00a4 | 1578 | |
1579 | tree | |
35771a9a | 1580 | convert (tree type, tree expr) |
d81e00a4 | 1581 | { |
c4a8ac95 | 1582 | tree intype; |
1583 | ||
1584 | if (type == error_mark_node || expr == error_mark_node) | |
1585 | return error_mark_node; | |
1586 | ||
c4a8ac95 | 1587 | intype = TREE_TYPE (expr); |
1588 | ||
6686e84d | 1589 | if (POINTER_TYPE_P (type) && POINTER_TYPE_P (intype)) |
d2c63826 | 1590 | return build_nop (type, expr); |
c4a8ac95 | 1591 | |
b981525c | 1592 | return ocp_convert (type, expr, CONV_BACKEND_CONVERT, |
c4698a21 | 1593 | LOOKUP_NORMAL|LOOKUP_NO_CONVERSION, |
1594 | tf_warning_or_error); | |
d81e00a4 | 1595 | } |
1596 | ||
c4a8ac95 | 1597 | /* Like cp_convert, except permit conversions to take place which |
471086d6 | 1598 | are not normally allowed due to access restrictions |
1599 | (such as conversion from sub-type to private super-type). */ | |
96624a9e | 1600 | |
471086d6 | 1601 | tree |
c4698a21 | 1602 | convert_force (tree type, tree expr, int convtype, tsubst_flags_t complain) |
471086d6 | 1603 | { |
cd16867a | 1604 | tree e = expr; |
1605 | enum tree_code code = TREE_CODE (type); | |
471086d6 | 1606 | |
1607 | if (code == REFERENCE_TYPE) | |
d2c63826 | 1608 | return convert_to_reference (type, e, CONV_C_CAST, 0, |
1609 | NULL_TREE, complain); | |
471086d6 | 1610 | |
1611 | if (code == POINTER_TYPE) | |
d2c63826 | 1612 | return convert_to_pointer_force (type, e, complain); |
471086d6 | 1613 | |
ac9386a0 | 1614 | /* From typeck.c convert_for_assignment */ |
c21c015b | 1615 | if (((TYPE_PTR_P (TREE_TYPE (e)) && TREE_CODE (e) == ADDR_EXPR |
471086d6 | 1616 | && TREE_CODE (TREE_TYPE (TREE_TYPE (e))) == METHOD_TYPE) |
ac9386a0 | 1617 | || integer_zerop (e) |
1618 | || TYPE_PTRMEMFUNC_P (TREE_TYPE (e))) | |
471086d6 | 1619 | && TYPE_PTRMEMFUNC_P (type)) |
cb02169c | 1620 | /* compatible pointer to member functions. */ |
1621 | return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), e, 1, | |
c4698a21 | 1622 | /*c_cast_p=*/1, complain); |
a74e8896 | 1623 | |
c4698a21 | 1624 | return ocp_convert (type, e, CONV_C_CAST|convtype, LOOKUP_NORMAL, complain); |
471086d6 | 1625 | } |
1626 | ||
471086d6 | 1627 | /* Convert an aggregate EXPR to type XTYPE. If a conversion |
1628 | exists, return the attempted conversion. This may | |
1629 | return ERROR_MARK_NODE if the conversion is not | |
1630 | allowed (references private members, etc). | |
1631 | If no conversion exists, NULL_TREE is returned. | |
1632 | ||
ce28ee2e | 1633 | FIXME: Ambiguity checking is wrong. Should choose one by the implicit |
1634 | object parameter, or by the second standard conversion sequence if | |
1635 | that doesn't do it. This will probably wait for an overloading rewrite. | |
1636 | (jason 8/9/95) */ | |
471086d6 | 1637 | |
ef9571e5 | 1638 | static tree |
8999978b | 1639 | build_type_conversion (tree xtype, tree expr) |
471086d6 | 1640 | { |
1641 | /* C++: check to see if we can convert this aggregate type | |
bcf789d7 | 1642 | into the required type. */ |
66bbeb85 | 1643 | return build_user_type_conversion (xtype, expr, LOOKUP_NORMAL, |
1644 | tf_warning_or_error); | |
471086d6 | 1645 | } |
1646 | ||
1e66592c | 1647 | /* Convert the given EXPR to one of a group of types suitable for use in an |
1648 | expression. DESIRES is a combination of various WANT_* flags (q.v.) | |
35771a9a | 1649 | which indicates which types are suitable. If COMPLAIN is true, complain |
1e66592c | 1650 | about ambiguity; otherwise, the caller will deal with it. */ |
471086d6 | 1651 | |
1e66592c | 1652 | tree |
35771a9a | 1653 | build_expr_type_conversion (int desires, tree expr, bool complain) |
471086d6 | 1654 | { |
1e66592c | 1655 | tree basetype = TREE_TYPE (expr); |
6a44e72e | 1656 | tree conv = NULL_TREE; |
bdd152ce | 1657 | tree winner = NULL_TREE; |
471086d6 | 1658 | |
9031d10b | 1659 | if (expr == null_node |
1660 | && (desires & WANT_INT) | |
954885ed | 1661 | && !(desires & WANT_NULL)) |
db30b351 | 1662 | { |
1663 | source_location loc = | |
1664 | expansion_point_location_if_in_system_header (input_location); | |
1665 | ||
1666 | warning_at (loc, OPT_Wconversion_null, | |
1667 | "converting NULL to non-pointer type"); | |
1668 | } | |
9031d10b | 1669 | |
3d411d73 | 1670 | if (basetype == error_mark_node) |
1671 | return error_mark_node; | |
1672 | ||
95397ff9 | 1673 | if (! MAYBE_CLASS_TYPE_P (basetype)) |
bdd152ce | 1674 | switch (TREE_CODE (basetype)) |
1675 | { | |
1676 | case INTEGER_TYPE: | |
954885ed | 1677 | if ((desires & WANT_NULL) && null_ptr_cst_p (expr)) |
bdd152ce | 1678 | return expr; |
e3533433 | 1679 | /* fall through. */ |
bdd152ce | 1680 | |
1681 | case BOOLEAN_TYPE: | |
1682 | return (desires & WANT_INT) ? expr : NULL_TREE; | |
1683 | case ENUMERAL_TYPE: | |
1684 | return (desires & WANT_ENUM) ? expr : NULL_TREE; | |
1685 | case REAL_TYPE: | |
1686 | return (desires & WANT_FLOAT) ? expr : NULL_TREE; | |
1687 | case POINTER_TYPE: | |
1688 | return (desires & WANT_POINTER) ? expr : NULL_TREE; | |
9031d10b | 1689 | |
bdd152ce | 1690 | case FUNCTION_TYPE: |
1691 | case ARRAY_TYPE: | |
4405c1ad | 1692 | return (desires & WANT_POINTER) ? decay_conversion (expr, |
1693 | tf_warning_or_error) | |
653e5405 | 1694 | : NULL_TREE; |
96ec9e30 | 1695 | |
64ec1ad6 | 1696 | case COMPLEX_TYPE: |
96ec9e30 | 1697 | case VECTOR_TYPE: |
64ec1ad6 | 1698 | if ((desires & WANT_VECTOR_OR_COMPLEX) == 0) |
96ec9e30 | 1699 | return NULL_TREE; |
1700 | switch (TREE_CODE (TREE_TYPE (basetype))) | |
1701 | { | |
1702 | case INTEGER_TYPE: | |
1703 | case BOOLEAN_TYPE: | |
1704 | return (desires & WANT_INT) ? expr : NULL_TREE; | |
1705 | case ENUMERAL_TYPE: | |
1706 | return (desires & WANT_ENUM) ? expr : NULL_TREE; | |
1707 | case REAL_TYPE: | |
1708 | return (desires & WANT_FLOAT) ? expr : NULL_TREE; | |
1709 | default: | |
1710 | return NULL_TREE; | |
1711 | } | |
1712 | ||
bdd152ce | 1713 | default: |
1714 | return NULL_TREE; | |
1715 | } | |
1716 | ||
1717 | /* The code for conversions from class type is currently only used for | |
1718 | delete expressions. Other expressions are handled by build_new_op. */ | |
a5f2d620 | 1719 | if (!complete_type_or_maybe_complain (basetype, expr, complain)) |
f8182e08 | 1720 | return error_mark_node; |
1721 | if (!TYPE_HAS_CONVERSION (basetype)) | |
bdd152ce | 1722 | return NULL_TREE; |
1723 | ||
9960d752 | 1724 | for (conv = lookup_conversions (basetype); conv; conv = TREE_CHAIN (conv)) |
bdd152ce | 1725 | { |
1726 | int win = 0; | |
1727 | tree candidate; | |
1728 | tree cand = TREE_VALUE (conv); | |
6767ca9a | 1729 | cand = OVL_FIRST (cand); |
bdd152ce | 1730 | |
1731 | if (winner && winner == cand) | |
1732 | continue; | |
1733 | ||
cf7aa2e5 | 1734 | if (DECL_NONCONVERTING_P (cand)) |
1735 | continue; | |
1736 | ||
ef4534a3 | 1737 | candidate = non_reference (TREE_TYPE (TREE_TYPE (cand))); |
bdd152ce | 1738 | |
1739 | switch (TREE_CODE (candidate)) | |
1740 | { | |
1741 | case BOOLEAN_TYPE: | |
1742 | case INTEGER_TYPE: | |
1743 | win = (desires & WANT_INT); break; | |
1744 | case ENUMERAL_TYPE: | |
1745 | win = (desires & WANT_ENUM); break; | |
1746 | case REAL_TYPE: | |
1747 | win = (desires & WANT_FLOAT); break; | |
1748 | case POINTER_TYPE: | |
1749 | win = (desires & WANT_POINTER); break; | |
1750 | ||
64ec1ad6 | 1751 | case COMPLEX_TYPE: |
96ec9e30 | 1752 | case VECTOR_TYPE: |
64ec1ad6 | 1753 | if ((desires & WANT_VECTOR_OR_COMPLEX) == 0) |
96ec9e30 | 1754 | break; |
1755 | switch (TREE_CODE (TREE_TYPE (candidate))) | |
1756 | { | |
1757 | case BOOLEAN_TYPE: | |
1758 | case INTEGER_TYPE: | |
1759 | win = (desires & WANT_INT); break; | |
1760 | case ENUMERAL_TYPE: | |
1761 | win = (desires & WANT_ENUM); break; | |
1762 | case REAL_TYPE: | |
1763 | win = (desires & WANT_FLOAT); break; | |
1764 | default: | |
1765 | break; | |
1766 | } | |
1767 | break; | |
1768 | ||
bdd152ce | 1769 | default: |
9c4c1195 | 1770 | /* A wildcard could be instantiated to match any desired |
1771 | type, but we can't deduce the template argument. */ | |
1772 | if (WILDCARD_TYPE_P (candidate)) | |
1773 | win = true; | |
bdd152ce | 1774 | break; |
1775 | } | |
1776 | ||
1777 | if (win) | |
1778 | { | |
9c4c1195 | 1779 | if (TREE_CODE (cand) == TEMPLATE_DECL) |
1780 | { | |
1781 | if (complain) | |
1782 | error ("default type conversion can't deduce template" | |
1783 | " argument for %qD", cand); | |
1784 | return error_mark_node; | |
1785 | } | |
1786 | ||
bdd152ce | 1787 | if (winner) |
1788 | { | |
609c541f | 1789 | tree winner_type |
1790 | = non_reference (TREE_TYPE (TREE_TYPE (winner))); | |
1791 | ||
1792 | if (!same_type_ignoring_top_level_qualifiers_p (winner_type, | |
1793 | candidate)) | |
bdd152ce | 1794 | { |
609c541f | 1795 | if (complain) |
1796 | { | |
1797 | error ("ambiguous default type conversion from %qT", | |
1798 | basetype); | |
392214f6 | 1799 | inform (input_location, |
1800 | " candidate conversions include %qD and %qD", | |
1801 | winner, cand); | |
609c541f | 1802 | } |
1803 | return error_mark_node; | |
bdd152ce | 1804 | } |
bdd152ce | 1805 | } |
609c541f | 1806 | |
1807 | winner = cand; | |
bdd152ce | 1808 | } |
1809 | } | |
1e66592c | 1810 | |
bdd152ce | 1811 | if (winner) |
1812 | { | |
ef4534a3 | 1813 | tree type = non_reference (TREE_TYPE (TREE_TYPE (winner))); |
66bbeb85 | 1814 | return build_user_type_conversion (type, expr, LOOKUP_NORMAL, |
1815 | tf_warning_or_error); | |
471086d6 | 1816 | } |
1e66592c | 1817 | |
985e9ee0 | 1818 | return NULL_TREE; |
471086d6 | 1819 | } |
bc3887cf | 1820 | |
96624a9e | 1821 | /* Implements integral promotion (4.1) and float->double promotion. */ |
1822 | ||
bc3887cf | 1823 | tree |
35771a9a | 1824 | type_promotes_to (tree type) |
bc3887cf | 1825 | { |
2b3c93a3 | 1826 | tree promoted_type; |
1827 | ||
ce28ee2e | 1828 | if (type == error_mark_node) |
1829 | return error_mark_node; | |
1830 | ||
bc3887cf | 1831 | type = TYPE_MAIN_VARIANT (type); |
bb0726a1 | 1832 | |
2b3c93a3 | 1833 | /* Check for promotions of target-defined types first. */ |
1834 | promoted_type = targetm.promoted_type (type); | |
1835 | if (promoted_type) | |
1836 | return promoted_type; | |
1837 | ||
bb0726a1 | 1838 | /* bool always promotes to int (not unsigned), even if it's the same |
1839 | size. */ | |
9e1a8234 | 1840 | if (TREE_CODE (type) == BOOLEAN_TYPE) |
bb0726a1 | 1841 | type = integer_type_node; |
1842 | ||
1843 | /* Normally convert enums to int, but convert wide enums to something | |
74b777e5 | 1844 | wider. Scoped enums don't promote, but pretend they do for backward |
1845 | ABI bug compatibility wrt varargs. */ | |
bb0726a1 | 1846 | else if (TREE_CODE (type) == ENUMERAL_TYPE |
924bbf02 | 1847 | || type == char16_type_node |
1848 | || type == char32_type_node | |
bb0726a1 | 1849 | || type == wchar_type_node) |
6c9497b1 | 1850 | { |
1851 | int precision = MAX (TYPE_PRECISION (type), | |
1852 | TYPE_PRECISION (integer_type_node)); | |
771d21fa | 1853 | tree totype = c_common_type_for_size (precision, 0); |
74b777e5 | 1854 | tree prom = type; |
1855 | if (TREE_CODE (prom) == ENUMERAL_TYPE) | |
1856 | prom = ENUM_UNDERLYING_TYPE (prom); | |
1857 | if (TYPE_UNSIGNED (prom) | |
1858 | && ! int_fits_type_p (TYPE_MAX_VALUE (prom), totype)) | |
1859 | prom = c_common_type_for_size (precision, 1); | |
1860 | else | |
1861 | prom = totype; | |
72fc0f64 | 1862 | if (SCOPED_ENUM_P (type)) |
74b777e5 | 1863 | { |
1864 | if (abi_version_crosses (6) | |
1865 | && TYPE_MODE (prom) != TYPE_MODE (type)) | |
1866 | warning (OPT_Wabi, "scoped enum %qT passed through ... as " | |
1867 | "%qT before -fabi-version=6, %qT after", | |
1868 | type, prom, ENUM_UNDERLYING_TYPE (type)); | |
1869 | if (!abi_version_at_least (6)) | |
1870 | type = prom; | |
1871 | } | |
6c9497b1 | 1872 | else |
74b777e5 | 1873 | type = prom; |
6c9497b1 | 1874 | } |
d7aeef06 | 1875 | else if (c_promoting_integer_type_p (type)) |
bc3887cf | 1876 | { |
d0acef9e | 1877 | /* Retain unsignedness if really not getting bigger. */ |
78a8ed03 | 1878 | if (TYPE_UNSIGNED (type) |
d0acef9e | 1879 | && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)) |
bc3887cf | 1880 | type = unsigned_type_node; |
1881 | else | |
1882 | type = integer_type_node; | |
1883 | } | |
1884 | else if (type == float_type_node) | |
1885 | type = double_type_node; | |
9031d10b | 1886 | |
a681799d | 1887 | return type; |
bc3887cf | 1888 | } |
668ae905 | 1889 | |
668ae905 | 1890 | /* The routines below this point are carefully written to conform to |
1891 | the standard. They use the same terminology, and follow the rules | |
1892 | closely. Although they are used only in pt.c at the moment, they | |
1893 | should presumably be used everywhere in the future. */ | |
1894 | ||
0a8a2108 | 1895 | /* True iff EXPR can be converted to TYPE via a qualification conversion. |
1896 | Callers should check for identical types before calling this function. */ | |
1897 | ||
1898 | bool | |
1899 | can_convert_qual (tree type, tree expr) | |
1900 | { | |
1901 | tree expr_type = TREE_TYPE (expr); | |
1902 | gcc_assert (!same_type_p (type, expr_type)); | |
1903 | ||
1904 | if (TYPE_PTR_P (type) && TYPE_PTR_P (expr_type)) | |
1905 | return comp_ptr_ttypes (TREE_TYPE (type), TREE_TYPE (expr_type)); | |
1906 | else if (TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (expr_type)) | |
1907 | return (same_type_p (TYPE_PTRMEM_CLASS_TYPE (type), | |
1908 | TYPE_PTRMEM_CLASS_TYPE (expr_type)) | |
1909 | && comp_ptr_ttypes (TYPE_PTRMEM_POINTED_TO_TYPE (type), | |
1910 | TYPE_PTRMEM_POINTED_TO_TYPE (expr_type))); | |
1911 | else | |
1912 | return false; | |
1913 | } | |
1914 | ||
1146f179 | 1915 | /* Attempt to perform qualification conversions on EXPR to convert it |
1916 | to TYPE. Return the resulting expression, or error_mark_node if | |
1917 | the conversion was impossible. */ | |
1918 | ||
9031d10b | 1919 | tree |
35771a9a | 1920 | perform_qualification_conversions (tree type, tree expr) |
668ae905 | 1921 | { |
1bc16cab | 1922 | tree expr_type; |
1923 | ||
1924 | expr_type = TREE_TYPE (expr); | |
1925 | ||
3b087710 | 1926 | if (same_type_p (type, expr_type)) |
1927 | return expr; | |
0a8a2108 | 1928 | else if (can_convert_qual (type, expr)) |
1bc16cab | 1929 | return build_nop (type, expr); |
1146f179 | 1930 | else |
1931 | return error_mark_node; | |
668ae905 | 1932 | } |
6d02e6b2 | 1933 | |
1934 | /* True iff T is a transaction-safe function type. */ | |
1935 | ||
1936 | bool | |
1937 | tx_safe_fn_type_p (tree t) | |
1938 | { | |
1939 | if (TREE_CODE (t) != FUNCTION_TYPE | |
1940 | && TREE_CODE (t) != METHOD_TYPE) | |
1941 | return false; | |
1942 | return !!lookup_attribute ("transaction_safe", TYPE_ATTRIBUTES (t)); | |
1943 | } | |
1944 | ||
1945 | /* Return the transaction-unsafe variant of transaction-safe function type | |
1946 | T. */ | |
1947 | ||
1948 | tree | |
1949 | tx_unsafe_fn_variant (tree t) | |
1950 | { | |
1951 | gcc_assert (tx_safe_fn_type_p (t)); | |
1952 | tree attrs = remove_attribute ("transaction_safe", | |
1953 | TYPE_ATTRIBUTES (t)); | |
1954 | return cp_build_type_attribute_variant (t, attrs); | |
1955 | } | |
1956 | ||
1957 | /* Return true iff FROM can convert to TO by a transaction-safety | |
1958 | conversion. */ | |
1959 | ||
2e9e9363 | 1960 | static bool |
6d02e6b2 | 1961 | can_convert_tx_safety (tree to, tree from) |
1962 | { | |
1963 | return (flag_tm && tx_safe_fn_type_p (from) | |
1964 | && same_type_p (to, tx_unsafe_fn_variant (from))); | |
1965 | } | |
2e9e9363 | 1966 | |
1967 | /* Return true iff FROM can convert to TO by dropping noexcept. */ | |
1968 | ||
1969 | static bool | |
1970 | noexcept_conv_p (tree to, tree from) | |
1971 | { | |
1972 | if (!flag_noexcept_type) | |
1973 | return false; | |
1974 | ||
1975 | tree t = non_reference (to); | |
1976 | tree f = from; | |
1977 | if (TYPE_PTRMEMFUNC_P (t) | |
1978 | && TYPE_PTRMEMFUNC_P (f)) | |
1979 | { | |
1980 | t = TYPE_PTRMEMFUNC_FN_TYPE (t); | |
1981 | f = TYPE_PTRMEMFUNC_FN_TYPE (f); | |
1982 | } | |
1983 | if (TREE_CODE (t) == POINTER_TYPE | |
1984 | && TREE_CODE (f) == POINTER_TYPE) | |
1985 | { | |
1986 | t = TREE_TYPE (t); | |
1987 | f = TREE_TYPE (f); | |
1988 | } | |
1989 | tree_code code = TREE_CODE (f); | |
1990 | if (TREE_CODE (t) != code) | |
1991 | return false; | |
1992 | if (code != FUNCTION_TYPE && code != METHOD_TYPE) | |
1993 | return false; | |
1994 | if (!type_throw_all_p (t) | |
1995 | || type_throw_all_p (f)) | |
1996 | return false; | |
1997 | tree v = build_exception_variant (f, NULL_TREE); | |
1998 | return same_type_p (t, v); | |
1999 | } | |
2000 | ||
2001 | /* Return true iff FROM can convert to TO by a function pointer conversion. */ | |
2002 | ||
2003 | bool | |
2004 | fnptr_conv_p (tree to, tree from) | |
2005 | { | |
2006 | tree t = non_reference (to); | |
2007 | tree f = from; | |
2008 | if (TYPE_PTRMEMFUNC_P (t) | |
2009 | && TYPE_PTRMEMFUNC_P (f)) | |
2010 | { | |
2011 | t = TYPE_PTRMEMFUNC_FN_TYPE (t); | |
2012 | f = TYPE_PTRMEMFUNC_FN_TYPE (f); | |
2013 | } | |
2014 | if (TREE_CODE (t) == POINTER_TYPE | |
2015 | && TREE_CODE (f) == POINTER_TYPE) | |
2016 | { | |
2017 | t = TREE_TYPE (t); | |
2018 | f = TREE_TYPE (f); | |
2019 | } | |
2020 | ||
2021 | return (noexcept_conv_p (t, f) | |
2022 | || can_convert_tx_safety (t, f)); | |
2023 | } | |
2024 | ||
2104a0fd | 2025 | /* Return FN with any NOP_EXPRs stripped that represent function pointer |
2026 | conversions or conversions to the same type. */ | |
2e9e9363 | 2027 | |
2028 | tree | |
2029 | strip_fnptr_conv (tree fn) | |
2030 | { | |
2031 | while (TREE_CODE (fn) == NOP_EXPR) | |
2032 | { | |
2033 | tree op = TREE_OPERAND (fn, 0); | |
2104a0fd | 2034 | tree ft = TREE_TYPE (fn); |
2035 | tree ot = TREE_TYPE (op); | |
2036 | if (same_type_p (ft, ot) | |
2037 | || fnptr_conv_p (ft, ot)) | |
2e9e9363 | 2038 | fn = op; |
2039 | else | |
2040 | break; | |
2041 | } | |
2042 | return fn; | |
2043 | } |