gcc/cp/typeck2.c

   1 /* Report error messages, build initializers, and perform
   2    some front-end optimizations for C++ compiler.
   3    Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
   4    1999, 2000, 2001, 2002 Free Software Foundation, Inc.
   5    Hacked by Michael Tiemann (tiemann@cygnus.com)
   6
   7 This file is part of GCC.
   8
   9 GCC is free software; you can redistribute it and/or modify
  10 it under the terms of the GNU General Public License as published by
  11 the Free Software Foundation; either version 2, or (at your option)
  12 any later version.
  13
  14 GCC is distributed in the hope that it will be useful,
  15 but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 GNU General Public License for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with GCC; see the file COPYING.  If not, write to
  21 the Free Software Foundation, 59 Temple Place - Suite 330,
  22 Boston, MA 02111-1307, USA.  */
  23
  24
  25 /* This file is part of the C++ front end.
  26    It contains routines to build C++ expressions given their operands,
  27    including computing the types of the result, C and C++ specific error
  28    checks, and some optimization.
  29
  30    There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
  31    and to process initializations in declarations (since they work
  32    like a strange sort of assignment).  */
  33
  34 #include "config.h"
  35 #include "system.h"
  36 #include "coretypes.h"
  37 #include "tm.h"
  38 #include "tree.h"
  39 #include "cp-tree.h"
  40 #include "flags.h"
  41 #include "toplev.h"
  42 #include "output.h"
  43 #include "diagnostic.h"
  44
  45 static tree process_init_constructor PARAMS ((tree, tree, tree *));
  46
  47 /* Print an error message stemming from an attempt to use
  48    BASETYPE as a base class for TYPE.  */
  49
  50 tree
  51 error_not_base_type (basetype, type)
  52      tree basetype, type;
  53 {
  54   if (TREE_CODE (basetype) == FUNCTION_DECL)
  55     basetype = DECL_CONTEXT (basetype);
  56   error ("type `%T' is not a base type for type `%T'", basetype, type);
  57   return error_mark_node;
  58 }
  59
  60 tree
  61 binfo_or_else (base, type)
  62      tree base, type;
  63 {
  64   tree binfo = lookup_base (type, base, ba_ignore, NULL);
  65
  66   if (binfo == error_mark_node)
  67     return NULL_TREE;
  68   else if (!binfo)
  69     error_not_base_type (base, type);
  70   return binfo;
  71 }
  72
  73 /* According to ARM $7.1.6, "A `const' object may be initialized, but its
  74    value may not be changed thereafter.  Thus, we emit hard errors for these,
  75    rather than just pedwarns.  If `SOFT' is 1, then we just pedwarn.  (For
  76    example, conversions to references.)  */
  77
  78 void
  79 readonly_error (arg, string, soft)
  80      tree arg;
  81      const char *string;
  82      int soft;
  83 {
  84   const char *fmt;
  85   void (*fn) PARAMS ((const char *, ...));
  86
  87   if (soft)
  88     fn = pedwarn;
  89   else
  90     fn = error;
  91
  92   if (TREE_CODE (arg) == COMPONENT_REF)
  93     {
  94       if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
  95         fmt = "%s of data-member `%D' in read-only structure";
  96       else
  97         fmt = "%s of read-only data-member `%D'";
  98       (*fn) (fmt, string, TREE_OPERAND (arg, 1));
  99     }
 100   else if (TREE_CODE (arg) == VAR_DECL)
 101     {
 102       if (DECL_LANG_SPECIFIC (arg)
 103           && DECL_IN_AGGR_P (arg)
 104           && !TREE_STATIC (arg))
 105         fmt = "%s of constant field `%D'";
 106       else
 107         fmt = "%s of read-only variable `%D'";
 108       (*fn) (fmt, string, arg);
 109     }
 110   else if (TREE_CODE (arg) == PARM_DECL)
 111     (*fn) ("%s of read-only parameter `%D'", string, arg);
 112   else if (TREE_CODE (arg) == INDIRECT_REF
 113            && TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0))) == REFERENCE_TYPE
 114            && (TREE_CODE (TREE_OPERAND (arg, 0)) == VAR_DECL
 115                || TREE_CODE (TREE_OPERAND (arg, 0)) == PARM_DECL))
 116     (*fn) ("%s of read-only reference `%D'", string, TREE_OPERAND (arg, 0));
 117   else if (TREE_CODE (arg) == RESULT_DECL)
 118     (*fn) ("%s of read-only named return value `%D'", string, arg);
 119   else if (TREE_CODE (arg) == FUNCTION_DECL)
 120     (*fn) ("%s of function `%D'", string, arg);
 121   else
 122     (*fn) ("%s of read-only location", string);
 123 }
 124
 125 /* If TYPE has abstract virtual functions, issue an error about trying
 126    to create an object of that type.  DECL is the object declared, or
 127    NULL_TREE if the declaration is unavailable.  Returns 1 if an error
 128    occurred; zero if all was well.  */
 129
 130 int
 131 abstract_virtuals_error (decl, type)
 132      tree decl;
 133      tree type;
 134 {
 135   tree u;
 136   tree tu;
 137
 138   if (!CLASS_TYPE_P (type) || !CLASSTYPE_PURE_VIRTUALS (type))
 139     return 0;
 140
 141   if (!TYPE_SIZE (type))
 142     /* TYPE is being defined, and during that time
 143        CLASSTYPE_PURE_VIRTUALS holds the inline friends.  */
 144     return 0;
 145
 146   u = CLASSTYPE_PURE_VIRTUALS (type);
 147   if (decl)
 148     {
 149       if (TREE_CODE (decl) == RESULT_DECL)
 150         return 0;
 151
 152       if (TREE_CODE (decl) == VAR_DECL)
 153         error ("cannot declare variable `%D' to be of type `%T'",
 154                     decl, type);
 155       else if (TREE_CODE (decl) == PARM_DECL)
 156         error ("cannot declare parameter `%D' to be of type `%T'",
 157                     decl, type);
 158       else if (TREE_CODE (decl) == FIELD_DECL)
 159         error ("cannot declare field `%D' to be of type `%T'",
 160                     decl, type);
 161       else if (TREE_CODE (decl) == FUNCTION_DECL
 162                && TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE)
 163         error ("invalid return type for member function `%#D'", decl);
 164       else if (TREE_CODE (decl) == FUNCTION_DECL)
 165         error ("invalid return type for function `%#D'", decl);
 166     }
 167   else
 168     error ("cannot allocate an object of type `%T'", type);
 169
 170   /* Only go through this once.  */
 171   if (TREE_PURPOSE (u) == NULL_TREE)
 172     {
 173       TREE_PURPOSE (u) = error_mark_node;
 174
 175       error ("  because the following virtual functions are abstract:");
 176       for (tu = u; tu; tu = TREE_CHAIN (tu))
 177         cp_error_at ("\t%#D", TREE_VALUE (tu));
 178     }
 179   else
 180     error ("  since type `%T' has abstract virtual functions", type);
 181
 182   return 1;
 183 }
 184
 185 /* Print an error message for invalid use of an incomplete type.
 186    VALUE is the expression that was used (or 0 if that isn't known)
 187    and TYPE is the type that was invalid.  DIAG_TYPE indicates the
 188    type of diagnostic:  0 for an error, 1 for a warning, 2 for a
 189    pedwarn.  */
 190
 191 void
 192 cxx_incomplete_type_diagnostic (value, type, diag_type)
 193      tree value;
 194      tree type;
 195      int diag_type;
 196 {
 197   int decl = 0;
 198   void (*p_msg) PARAMS ((const char *, ...));
 199   void (*p_msg_at) PARAMS ((const char *, ...));
 200
 201   if (diag_type == 1)
 202     {
 203       p_msg = warning;
 204       p_msg_at = cp_warning_at;
 205     }
 206   else if (diag_type == 2)
 207     {
 208       p_msg = pedwarn;
 209       p_msg_at = cp_pedwarn_at;
 210     }
 211   else
 212     {
 213       p_msg = error;
 214       p_msg_at = cp_error_at;
 215     }
 216
 217   /* Avoid duplicate error message.  */
 218   if (TREE_CODE (type) == ERROR_MARK)
 219     return;
 220
 221   if (value != 0 && (TREE_CODE (value) == VAR_DECL
 222                      || TREE_CODE (value) == PARM_DECL
 223                      || TREE_CODE (value) == FIELD_DECL))
 224     {
 225       (*p_msg_at) ("`%D' has incomplete type", value);
 226       decl = 1;
 227     }
 228 retry:
 229   /* We must print an error message.  Be clever about what it says.  */
 230
 231   switch (TREE_CODE (type))
 232     {
 233     case RECORD_TYPE:
 234     case UNION_TYPE:
 235     case ENUMERAL_TYPE:
 236       if (!decl)
 237         (*p_msg) ("invalid use of undefined type `%#T'", type);
 238       if (!TYPE_TEMPLATE_INFO (type))
 239         (*p_msg_at) ("forward declaration of `%#T'", type);
 240       else
 241         (*p_msg_at) ("declaration of `%#T'", type);
 242       break;
 243
 244     case VOID_TYPE:
 245       (*p_msg) ("invalid use of `%T'", type);
 246       break;
 247
 248     case ARRAY_TYPE:
 249       if (TYPE_DOMAIN (type))
 250         {
 251           type = TREE_TYPE (type);
 252           goto retry;
 253         }
 254       (*p_msg) ("invalid use of array with unspecified bounds");
 255       break;
 256
 257     case OFFSET_TYPE:
 258     bad_member:
 259       (*p_msg) ("invalid use of member (did you forget the `&' ?)");
 260       break;
 261
 262     case TEMPLATE_TYPE_PARM:
 263       (*p_msg) ("invalid use of template type parameter");
 264       break;
 265
 266     case UNKNOWN_TYPE:
 267       if (value && TREE_CODE (value) == COMPONENT_REF)
 268         goto bad_member;
 269       else if (value && TREE_CODE (value) == ADDR_EXPR)
 270         (*p_msg) ("address of overloaded function with no contextual type information");
 271       else if (value && TREE_CODE (value) == OVERLOAD)
 272         (*p_msg) ("overloaded function with no contextual type information");
 273       else
 274         (*p_msg) ("insufficient contextual information to determine type");
 275       break;
 276
 277     default:
 278       abort ();
 279     }
 280 }
 281
 282 /* Backward-compatibility interface to incomplete_type_diagnostic;
 283    required by ../tree.c.  */
 284 #undef cxx_incomplete_type_error
 285 void
 286 cxx_incomplete_type_error (value, type)
 287      tree value;
 288      tree type;
 289 {
 290   cxx_incomplete_type_diagnostic (value, type, 0);
 291 }
 292
 293 \f
 294 /* Perform appropriate conversions on the initial value of a variable,
 295    store it in the declaration DECL,
 296    and print any error messages that are appropriate.
 297    If the init is invalid, store an ERROR_MARK.
 298
 299    C++: Note that INIT might be a TREE_LIST, which would mean that it is
 300    a base class initializer for some aggregate type, hopefully compatible
 301    with DECL.  If INIT is a single element, and DECL is an aggregate
 302    type, we silently convert INIT into a TREE_LIST, allowing a constructor
 303    to be called.
 304
 305    If INIT is a TREE_LIST and there is no constructor, turn INIT
 306    into a CONSTRUCTOR and use standard initialization techniques.
 307    Perhaps a warning should be generated?
 308
 309    Returns value of initializer if initialization could not be
 310    performed for static variable.  In that case, caller must do
 311    the storing.  */
 312
 313 tree
 314 store_init_value (decl, init)
 315      tree decl, init;
 316 {
 317   register tree value, type;
 318
 319   /* If variable's type was invalidly declared, just ignore it.  */
 320
 321   type = TREE_TYPE (decl);
 322   if (TREE_CODE (type) == ERROR_MARK)
 323     return NULL_TREE;
 324
 325   if (IS_AGGR_TYPE (type))
 326     {
 327       if (! TYPE_HAS_TRIVIAL_INIT_REF (type)
 328           && TREE_CODE (init) != CONSTRUCTOR)
 329         abort ();
 330
 331       if (TREE_CODE (init) == TREE_LIST)
 332         {
 333           error ("constructor syntax used, but no constructor declared for type `%T'", type);
 334           init = build_nt (CONSTRUCTOR, NULL_TREE, nreverse (init));
 335         }
 336     }
 337   else if (TREE_CODE (init) == TREE_LIST
 338            && TREE_TYPE (init) != unknown_type_node)
 339     {
 340       if (TREE_CODE (decl) == RESULT_DECL)
 341         {
 342           if (TREE_CHAIN (init))
 343             {
 344               warning ("comma expression used to initialize return value");
 345               init = build_compound_expr (init);
 346             }
 347           else
 348             init = TREE_VALUE (init);
 349         }
 350       else if (TREE_CODE (init) == TREE_LIST
 351                && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
 352         {
 353           error ("cannot initialize arrays using this syntax");
 354           return NULL_TREE;
 355         }
 356       else
 357         {
 358           /* We get here with code like `int a (2);' */
 359
 360           if (TREE_CHAIN (init) != NULL_TREE)
 361             {
 362               pedwarn ("initializer list being treated as compound expression");
 363               init = build_compound_expr (init);
 364             }
 365           else
 366             init = TREE_VALUE (init);
 367         }
 368     }
 369
 370   /* End of special C++ code.  */
 371
 372   /* Digest the specified initializer into an expression.  */
 373   value = digest_init (type, init, (tree *) 0);
 374
 375   /* Store the expression if valid; else report error.  */
 376
 377   if (TREE_CODE (value) == ERROR_MARK)
 378     ;
 379   /* Other code expects that initializers for objects of types that need
 380      constructing never make it into DECL_INITIAL, and passes 'init' to
 381      build_aggr_init without checking DECL_INITIAL.  So just return.  */
 382   else if (TYPE_NEEDS_CONSTRUCTING (type))
 383     return value;
 384   else if (TREE_STATIC (decl)
 385            && (! TREE_CONSTANT (value)
 386                || ! initializer_constant_valid_p (value, TREE_TYPE (value))
 387 #if 0
 388                /* A STATIC PUBLIC int variable doesn't have to be
 389                   run time inited when doing pic.  (mrs) */
 390                /* Since ctors and dtors are the only things that can
 391                   reference vtables, and they are always written down
 392                   the vtable definition, we can leave the
 393                   vtables in initialized data space.
 394                   However, other initialized data cannot be initialized
 395                   this way.  Instead a global file-level initializer
 396                   must do the job.  */
 397                || (flag_pic && !DECL_VIRTUAL_P (decl) && TREE_PUBLIC (decl))
 398 #endif
 399                ))
 400
 401     return value;
 402 #if 0 /* No, that's C.  jason 9/19/94 */
 403   else
 404     {
 405       if (pedantic && TREE_CODE (value) == CONSTRUCTOR)
 406         {
 407           if (! TREE_CONSTANT (value) || ! TREE_STATIC (value))
 408             pedwarn ("ISO C++ forbids non-constant aggregate initializer expressions");
 409         }
 410     }
 411 #endif
 412
 413   /* Store the VALUE in DECL_INITIAL.  If we're building a
 414      statement-tree we will actually expand the initialization later
 415      when we output this function.  */
 416   DECL_INITIAL (decl) = value;
 417   return NULL_TREE;
 418 }
 419
 420 \f
 421 /* Digest the parser output INIT as an initializer for type TYPE.
 422    Return a C expression of type TYPE to represent the initial value.
 423
 424    If TAIL is nonzero, it points to a variable holding a list of elements
 425    of which INIT is the first.  We update the list stored there by
 426    removing from the head all the elements that we use.
 427    Normally this is only one; we use more than one element only if
 428    TYPE is an aggregate and INIT is not a constructor.  */
 429
 430 tree
 431 digest_init (type, init, tail)
 432      tree type, init, *tail;
 433 {
 434   enum tree_code code = TREE_CODE (type);
 435   tree element = NULL_TREE;
 436   tree old_tail_contents = NULL_TREE;
 437   /* Nonzero if INIT is a braced grouping.  */
 438   int raw_constructor;
 439
 440   /* By default, assume we use one element from a list.
 441      We correct this later in the sole case where it is not true.  */
 442
 443   if (tail)
 444     {
 445       old_tail_contents = *tail;
 446       *tail = TREE_CHAIN (*tail);
 447     }
 448
 449   if (init == error_mark_node || (TREE_CODE (init) == TREE_LIST
 450                                   && TREE_VALUE (init) == error_mark_node))
 451     return error_mark_node;
 452
 453   if (TREE_CODE (init) == ERROR_MARK)
 454     /* __PRETTY_FUNCTION__'s initializer is a bogus expression inside
 455        a template function. This gets substituted during instantiation.  */
 456     return init;
 457
 458   /* We must strip the outermost array type when completing the type,
 459      because the its bounds might be incomplete at the moment.  */
 460   if (!complete_type_or_else (TREE_CODE (type) == ARRAY_TYPE
 461                               ? TREE_TYPE (type) : type, NULL_TREE))
 462     return error_mark_node;
 463
 464   /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue.  */
 465   if (TREE_CODE (init) == NON_LVALUE_EXPR)
 466     init = TREE_OPERAND (init, 0);
 467
 468   raw_constructor = (TREE_CODE (init) == CONSTRUCTOR
 469                      && TREE_HAS_CONSTRUCTOR (init));
 470
 471   if (raw_constructor
 472       && CONSTRUCTOR_ELTS (init) != 0
 473       && TREE_CHAIN (CONSTRUCTOR_ELTS (init)) == 0)
 474     {
 475       element = TREE_VALUE (CONSTRUCTOR_ELTS (init));
 476       /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue.  */
 477       if (element && TREE_CODE (element) == NON_LVALUE_EXPR)
 478         element = TREE_OPERAND (element, 0);
 479       if (element == error_mark_node)
 480         return element;
 481     }
 482
 483   /* Initialization of an array of chars from a string constant
 484      optionally enclosed in braces.  */
 485
 486   if (code == ARRAY_TYPE)
 487     {
 488       tree typ1;
 489
 490       if (TREE_CODE (init) == TREE_LIST)
 491         {
 492           error ("initializing array with parameter list");
 493           return error_mark_node;
 494         }
 495
 496       typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
 497       if (char_type_p (typ1)
 498           && ((init && TREE_CODE (init) == STRING_CST)
 499               || (element && TREE_CODE (element) == STRING_CST)))
 500         {
 501           tree string = element ? element : init;
 502
 503           if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (string)))
 504                != char_type_node)
 505               && TYPE_PRECISION (typ1) == BITS_PER_UNIT)
 506             {
 507               error ("char-array initialized from wide string");
 508               return error_mark_node;
 509             }
 510           if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (string)))
 511                == char_type_node)
 512               && TYPE_PRECISION (typ1) != BITS_PER_UNIT)
 513             {
 514               error ("int-array initialized from non-wide string");
 515               return error_mark_node;
 516             }
 517
 518           TREE_TYPE (string) = type;
 519           if (TYPE_DOMAIN (type) != 0
 520               && TREE_CONSTANT (TYPE_SIZE (type)))
 521             {
 522               register int size
 523                 = TREE_INT_CST_LOW (TYPE_SIZE (type));
 524               size = (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
 525               /* In C it is ok to subtract 1 from the length of the string
 526                  because it's ok to ignore the terminating null char that is
 527                  counted in the length of the constant, but in C++ this would
 528                  be invalid.  */
 529               if (size < TREE_STRING_LENGTH (string))
 530                 pedwarn ("initializer-string for array of chars is too long");
 531             }
 532           return string;
 533         }
 534     }
 535
 536   /* Handle scalar types, including conversions,
 537      and signature pointers and references.  */
 538
 539   if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
 540       || code == ENUMERAL_TYPE || code == REFERENCE_TYPE
 541       || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
 542       || TYPE_PTRMEMFUNC_P (type))
 543     {
 544       if (raw_constructor)
 545         {
 546           if (element == 0)
 547             {
 548               error ("initializer for scalar variable requires one element");
 549               return error_mark_node;
 550             }
 551           init = element;
 552         }
 553       while (TREE_CODE (init) == CONSTRUCTOR && TREE_HAS_CONSTRUCTOR (init))
 554         {
 555           pedwarn ("braces around scalar initializer for `%T'", type);
 556           init = CONSTRUCTOR_ELTS (init);
 557           if (TREE_CHAIN (init))
 558             pedwarn ("ignoring extra initializers for `%T'", type);
 559           init = TREE_VALUE (init);
 560         }
 561
 562       return convert_for_initialization (0, type, init, LOOKUP_NORMAL,
 563                                          "initialization", NULL_TREE, 0);
 564     }
 565
 566   /* Come here only for records and arrays (and unions with constructors).  */
 567
 568   if (COMPLETE_TYPE_P (type) && ! TREE_CONSTANT (TYPE_SIZE (type)))
 569     {
 570       error ("variable-sized object of type `%T' may not be initialized",
 571                 type);
 572       return error_mark_node;
 573     }
 574
 575   if (code == ARRAY_TYPE || code == VECTOR_TYPE || IS_AGGR_TYPE_CODE (code))
 576     {
 577       if (raw_constructor && TYPE_NON_AGGREGATE_CLASS (type)
 578           && TREE_HAS_CONSTRUCTOR (init))
 579         {
 580           error ("subobject of type `%T' must be initialized by constructor, not by `%E'",
 581                     type, init);
 582           return error_mark_node;
 583         }
 584       else if (raw_constructor)
 585         return process_init_constructor (type, init, (tree *)0);
 586       else if (can_convert_arg (type, TREE_TYPE (init), init)
 587                || TYPE_NON_AGGREGATE_CLASS (type))
 588         /* These are never initialized from multiple constructor elements.  */;
 589       else if (tail != 0)
 590         {
 591           *tail = old_tail_contents;
 592           return process_init_constructor (type, 0, tail);
 593         }
 594
 595       if (code != ARRAY_TYPE)
 596         {
 597           int flags = LOOKUP_NORMAL;
 598           /* Initialization from { } is copy-initialization.  */
 599           if (tail)
 600             flags |= LOOKUP_ONLYCONVERTING;
 601
 602           return convert_for_initialization (NULL_TREE, type, init, flags,
 603                                              "initialization", NULL_TREE, 0);
 604         }
 605     }
 606
 607   error ("invalid initializer");
 608   return error_mark_node;
 609 }
 610 \f
 611 /* Process a constructor for a variable of type TYPE.
 612    The constructor elements may be specified either with INIT or with ELTS,
 613    only one of which should be non-null.
 614
 615    If INIT is specified, it is a CONSTRUCTOR node which is specifically
 616    and solely for initializing this datum.
 617
 618    If ELTS is specified, it is the address of a variable containing
 619    a list of expressions.  We take as many elements as we need
 620    from the head of the list and update the list.
 621
 622    In the resulting constructor, TREE_CONSTANT is set if all elts are
 623    constant, and TREE_STATIC is set if, in addition, all elts are simple enough
 624    constants that the assembler and linker can compute them.  */
 625
 626 static tree
 627 process_init_constructor (type, init, elts)
 628      tree type, init, *elts;
 629 {
 630   register tree tail;
 631   /* List of the elements of the result constructor,
 632      in reverse order.  */
 633   register tree members = NULL;
 634   register tree next1;
 635   tree result;
 636   int allconstant = 1;
 637   int allsimple = 1;
 638   int erroneous = 0;
 639
 640   /* Make TAIL be the list of elements to use for the initialization,
 641      no matter how the data was given to us.  */
 642
 643   if (elts)
 644     {
 645       if (warn_missing_braces)
 646         warning ("aggregate has a partly bracketed initializer");
 647       tail = *elts;
 648     }
 649   else
 650     tail = CONSTRUCTOR_ELTS (init);
 651
 652   /* Gobble as many elements as needed, and make a constructor or initial value
 653      for each element of this aggregate.  Chain them together in result.
 654      If there are too few, use 0 for each scalar ultimate component.  */
 655
 656   if (TREE_CODE (type) == ARRAY_TYPE || TREE_CODE (type) == VECTOR_TYPE)
 657     {
 658       register long len;
 659       register int i;
 660
 661       if (TREE_CODE (type) == ARRAY_TYPE)
 662         {
 663           tree domain = TYPE_DOMAIN (type);
 664           if (domain)
 665             len = (TREE_INT_CST_LOW (TYPE_MAX_VALUE (domain))
 666                    - TREE_INT_CST_LOW (TYPE_MIN_VALUE (domain))
 667                    + 1);
 668           else
 669             len = -1;  /* Take as many as there are */
 670         }
 671       else
 672         {
 673           /* Vectors are like simple fixed-size arrays.  */
 674           len = TYPE_VECTOR_SUBPARTS (type);
 675         }
 676
 677       for (i = 0; len < 0 || i < len; i++)
 678         {
 679           if (tail)
 680             {
 681               if (TREE_PURPOSE (tail)
 682                   && (TREE_CODE (TREE_PURPOSE (tail)) != INTEGER_CST
 683                       || compare_tree_int (TREE_PURPOSE (tail), i) != 0))
 684                 sorry ("non-trivial labeled initializers");
 685
 686               if (TREE_VALUE (tail) != 0)
 687                 {
 688                   tree tail1 = tail;
 689                   next1 = digest_init (TREE_TYPE (type),
 690                                        TREE_VALUE (tail), &tail1);
 691                   if (next1 == error_mark_node)
 692                     return next1;
 693                   my_friendly_assert
 694                     (same_type_ignoring_top_level_qualifiers_p
 695                      (TREE_TYPE (type), TREE_TYPE (next1)),
 696                      981123);
 697                   my_friendly_assert (tail1 == 0
 698                                       || TREE_CODE (tail1) == TREE_LIST, 319);
 699                   if (tail == tail1 && len < 0)
 700                     {
 701                       error ("non-empty initializer for array of empty elements");
 702                       /* Just ignore what we were supposed to use.  */
 703                       tail1 = NULL_TREE;
 704                     }
 705                   tail = tail1;
 706                 }
 707               else
 708                 {
 709                   next1 = error_mark_node;
 710                   tail = TREE_CHAIN (tail);
 711                 }
 712             }
 713           else if (len < 0)
 714             /* We're done.  */
 715             break;
 716           else if (TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (type)))
 717             {
 718               /* If this type needs constructors run for
 719                  default-initialization, we can't rely on the backend to do it
 720                  for us, so build up TARGET_EXPRs.  If the type in question is
 721                  a class, just build one up; if it's an array, recurse.  */
 722
 723               if (IS_AGGR_TYPE (TREE_TYPE (type)))
 724                 next1 = build_functional_cast (TREE_TYPE (type), NULL_TREE);
 725               else
 726                 next1 = build (CONSTRUCTOR, NULL_TREE, NULL_TREE, NULL_TREE);
 727               next1 = digest_init (TREE_TYPE (type), next1, 0);
 728             }
 729           else if (! zero_init_p (TREE_TYPE (type)))
 730             next1 = build_zero_init (TREE_TYPE (type),
 731                                      /*static_storage_p=*/false);
 732           else
 733             /* The default zero-initialization is fine for us; don't
 734                add anything to the CONSTRUCTOR.  */
 735             break;
 736
 737           if (next1 == error_mark_node)
 738             erroneous = 1;
 739           else if (!TREE_CONSTANT (next1))
 740             allconstant = 0;
 741           else if (! initializer_constant_valid_p (next1, TREE_TYPE (next1)))
 742             allsimple = 0;
 743           members = tree_cons (size_int (i), next1, members);
 744         }
 745     }
 746   else if (TREE_CODE (type) == RECORD_TYPE)
 747     {
 748       register tree field;
 749
 750       if (tail)
 751         {
 752           if (TYPE_USES_VIRTUAL_BASECLASSES (type))
 753             {
 754               sorry ("initializer list for object of class with virtual base classes");
 755               return error_mark_node;
 756             }
 757
 758           if (TYPE_BINFO_BASETYPES (type))
 759             {
 760               sorry ("initializer list for object of class with base classes");
 761               return error_mark_node;
 762             }
 763
 764           if (TYPE_POLYMORPHIC_P (type))
 765             {
 766               sorry ("initializer list for object using virtual functions");
 767               return error_mark_node;
 768             }
 769         }
 770
 771       for (field = TYPE_FIELDS (type); field;
 772            field = TREE_CHAIN (field))
 773         {
 774           if (! DECL_NAME (field) && DECL_C_BIT_FIELD (field))
 775             {
 776               members = tree_cons (field, integer_zero_node, members);
 777               continue;
 778             }
 779
 780           if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
 781             continue;
 782
 783           if (tail)
 784             {
 785               if (TREE_PURPOSE (tail)
 786                   && TREE_PURPOSE (tail) != field
 787                   && TREE_PURPOSE (tail) != DECL_NAME (field))
 788                 sorry ("non-trivial labeled initializers");
 789
 790               if (TREE_VALUE (tail) != 0)
 791                 {
 792                   tree tail1 = tail;
 793
 794                   next1 = digest_init (TREE_TYPE (field),
 795                                        TREE_VALUE (tail), &tail1);
 796                   my_friendly_assert (tail1 == 0
 797                                       || TREE_CODE (tail1) == TREE_LIST, 320);
 798                   tail = tail1;
 799                 }
 800               else
 801                 {
 802                   next1 = error_mark_node;
 803                   tail = TREE_CHAIN (tail);
 804                 }
 805             }
 806           else if (TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (field)))
 807             {
 808               /* If this type needs constructors run for
 809                  default-initialization, we can't rely on the backend to do it
 810                  for us, so build up TARGET_EXPRs.  If the type in question is
 811                  a class, just build one up; if it's an array, recurse.  */
 812
 813               if (IS_AGGR_TYPE (TREE_TYPE (field)))
 814                 next1 = build_functional_cast (TREE_TYPE (field),
 815                                                NULL_TREE);
 816               else
 817                 {
 818                   next1 = build (CONSTRUCTOR, NULL_TREE, NULL_TREE,
 819                                  NULL_TREE);
 820                   if (init)
 821                     TREE_HAS_CONSTRUCTOR (next1)
 822                        = TREE_HAS_CONSTRUCTOR (init);
 823                 }
 824               next1 = digest_init (TREE_TYPE (field), next1, 0);
 825
 826               /* Warn when some struct elements are implicitly initialized.  */
 827               if (extra_warnings
 828                   && (!init || TREE_HAS_CONSTRUCTOR (init)))
 829                 warning ("missing initializer for member `%D'", field);
 830             }
 831           else
 832             {
 833               if (TREE_READONLY (field))
 834                 error ("uninitialized const member `%D'", field);
 835               else if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (TREE_TYPE (field)))
 836                 error ("member `%D' with uninitialized const fields",
 837                           field);
 838               else if (TREE_CODE (TREE_TYPE (field)) == REFERENCE_TYPE)
 839                 error ("member `%D' is uninitialized reference", field);
 840
 841               /* Warn when some struct elements are implicitly initialized
 842                  to zero.  */
 843               if (extra_warnings
 844                   && (!init || TREE_HAS_CONSTRUCTOR (init)))
 845                 warning ("missing initializer for member `%D'", field);
 846
 847               if (! zero_init_p (TREE_TYPE (field)))
 848                 next1 = build_zero_init (TREE_TYPE (field),
 849                                          /*static_storage_p=*/false);
 850               else
 851                 /* The default zero-initialization is fine for us; don't
 852                    add anything to the CONSTRUCTOR.  */
 853                 continue;
 854             }
 855
 856           if (next1 == error_mark_node)
 857             erroneous = 1;
 858           else if (!TREE_CONSTANT (next1))
 859             allconstant = 0;
 860           else if (! initializer_constant_valid_p (next1, TREE_TYPE (next1)))
 861             allsimple = 0;
 862           members = tree_cons (field, next1, members);
 863         }
 864     }
 865   else if (TREE_CODE (type) == UNION_TYPE
 866            /* If the initializer was empty, use default zero initialization.  */
 867            && tail)
 868     {
 869       register tree field = TYPE_FIELDS (type);
 870
 871       /* Find the first named field.  ANSI decided in September 1990
 872          that only named fields count here.  */
 873       while (field && (!DECL_NAME (field) || TREE_CODE (field) != FIELD_DECL))
 874         field = TREE_CHAIN (field);
 875
 876       /* If this element specifies a field, initialize via that field.  */
 877       if (TREE_PURPOSE (tail) != NULL_TREE)
 878         {
 879           int win = 0;
 880
 881           if (TREE_CODE (TREE_PURPOSE (tail)) == FIELD_DECL)
 882             /* Handle the case of a call by build_c_cast.  */
 883             field = TREE_PURPOSE (tail), win = 1;
 884           else if (TREE_CODE (TREE_PURPOSE (tail)) != IDENTIFIER_NODE)
 885             error ("index value instead of field name in union initializer");
 886           else
 887             {
 888               tree temp;
 889               for (temp = TYPE_FIELDS (type);
 890                    temp;
 891                    temp = TREE_CHAIN (temp))
 892                 if (DECL_NAME (temp) == TREE_PURPOSE (tail))
 893                   break;
 894               if (temp)
 895                 field = temp, win = 1;
 896               else
 897                 error ("no field `%D' in union being initialized",
 898                           TREE_PURPOSE (tail));
 899             }
 900           if (!win)
 901             TREE_VALUE (tail) = error_mark_node;
 902         }
 903       else if (field == 0)
 904         {
 905           error ("union `%T' with no named members cannot be initialized",
 906                     type);
 907           TREE_VALUE (tail) = error_mark_node;
 908         }
 909
 910       if (TREE_VALUE (tail) != 0)
 911         {
 912           tree tail1 = tail;
 913
 914           next1 = digest_init (TREE_TYPE (field),
 915                                TREE_VALUE (tail), &tail1);
 916           if (tail1 != 0 && TREE_CODE (tail1) != TREE_LIST)
 917             abort ();
 918           tail = tail1;
 919         }
 920       else
 921         {
 922           next1 = error_mark_node;
 923           tail = TREE_CHAIN (tail);
 924         }
 925
 926       if (next1 == error_mark_node)
 927         erroneous = 1;
 928       else if (!TREE_CONSTANT (next1))
 929         allconstant = 0;
 930       else if (initializer_constant_valid_p (next1, TREE_TYPE (next1)) == 0)
 931         allsimple = 0;
 932       members = tree_cons (field, next1, members);
 933     }
 934
 935   /* If arguments were specified as a list, just remove the ones we used.  */
 936   if (elts)
 937     *elts = tail;
 938   /* If arguments were specified as a constructor,
 939      complain unless we used all the elements of the constructor.  */
 940   else if (tail)
 941     pedwarn ("excess elements in aggregate initializer");
 942
 943   if (erroneous)
 944     return error_mark_node;
 945
 946   result = build (CONSTRUCTOR, type, NULL_TREE, nreverse (members));
 947   if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type) == NULL_TREE)
 948     complete_array_type (type, result, /*do_default=*/0);
 949   if (init)
 950     TREE_HAS_CONSTRUCTOR (result) = TREE_HAS_CONSTRUCTOR (init);
 951   if (allconstant) TREE_CONSTANT (result) = 1;
 952   if (allconstant && allsimple) TREE_STATIC (result) = 1;
 953   return result;
 954 }
 955 \f
 956 /* Given a structure or union value DATUM, construct and return
 957    the structure or union component which results from narrowing
 958    that value to the base specified in BASETYPE.  For example, given the
 959    hierarchy
 960
 961    class L { int ii; };
 962    class A : L { ... };
 963    class B : L { ... };
 964    class C : A, B { ... };
 965
 966    and the declaration
 967
 968    C x;
 969
 970    then the expression
 971
 972    x.A::ii refers to the ii member of the L part of
 973    the A part of the C object named by X.  In this case,
 974    DATUM would be x, and BASETYPE would be A.
 975
 976    I used to think that this was nonconformant, that the standard specified
 977    that first we look up ii in A, then convert x to an L& and pull out the
 978    ii part.  But in fact, it does say that we convert x to an A&; A here
 979    is known as the "naming class".  (jason 2000-12-19)
 980
 981    BINFO_P points to a variable initialized either to NULL_TREE or to the
 982    binfo for the specific base subobject we want to convert to.  */
 983
 984 tree
 985 build_scoped_ref (datum, basetype, binfo_p)
 986      tree datum;
 987      tree basetype;
 988      tree *binfo_p;
 989 {
 990   tree binfo;
 991
 992   if (datum == error_mark_node)
 993     return error_mark_node;
 994   if (*binfo_p)
 995     binfo = *binfo_p;
 996   else
 997     binfo = lookup_base (TREE_TYPE (datum), basetype, ba_check, NULL);
 998
 999   if (!binfo || binfo == error_mark_node)
1000     {
1001       *binfo_p = NULL_TREE;
1002       if (!binfo)
1003         error_not_base_type (basetype, TREE_TYPE (datum));
1004       return error_mark_node;
1005     }
1006
1007   *binfo_p = binfo;
1008   return build_base_path (PLUS_EXPR, datum, binfo, 1);
1009 }
1010
1011 /* Build a reference to an object specified by the C++ `->' operator.
1012    Usually this just involves dereferencing the object, but if the
1013    `->' operator is overloaded, then such overloads must be
1014    performed until an object which does not have the `->' operator
1015    overloaded is found.  An error is reported when circular pointer
1016    delegation is detected.  */
1017
1018 tree
1019 build_x_arrow (datum)
1020      tree datum;
1021 {
1022   tree types_memoized = NULL_TREE;
1023   register tree rval = datum;
1024   tree type = TREE_TYPE (rval);
1025   tree last_rval = NULL_TREE;
1026
1027   if (type == error_mark_node)
1028     return error_mark_node;
1029
1030   if (processing_template_decl)
1031     return build_min_nt (ARROW_EXPR, rval);
1032
1033   if (TREE_CODE (rval) == OFFSET_REF)
1034     {
1035       rval = resolve_offset_ref (datum);
1036       type = TREE_TYPE (rval);
1037     }
1038
1039   if (TREE_CODE (type) == REFERENCE_TYPE)
1040     {
1041       rval = convert_from_reference (rval);
1042       type = TREE_TYPE (rval);
1043     }
1044
1045   if (IS_AGGR_TYPE (type))
1046     {
1047       while ((rval = build_new_op (COMPONENT_REF, LOOKUP_NORMAL, rval,
1048                                    NULL_TREE, NULL_TREE)))
1049         {
1050           if (rval == error_mark_node)
1051             return error_mark_node;
1052
1053           if (value_member (TREE_TYPE (rval), types_memoized))
1054             {
1055               error ("circular pointer delegation detected");
1056               return error_mark_node;
1057             }
1058           else
1059             {
1060               types_memoized = tree_cons (NULL_TREE, TREE_TYPE (rval),
1061                                           types_memoized);
1062             }
1063           last_rval = rval;
1064         }
1065
1066       if (last_rval == NULL_TREE)
1067         {
1068           error ("base operand of `->' has non-pointer type `%T'", type);
1069           return error_mark_node;
1070         }
1071
1072       if (TREE_CODE (TREE_TYPE (last_rval)) == REFERENCE_TYPE)
1073         last_rval = convert_from_reference (last_rval);
1074     }
1075   else
1076     last_rval = default_conversion (rval);
1077
1078   if (TREE_CODE (TREE_TYPE (last_rval)) == POINTER_TYPE)
1079     return build_indirect_ref (last_rval, NULL);
1080
1081   if (types_memoized)
1082     error ("result of `operator->()' yields non-pointer result");
1083   else
1084     error ("base operand of `->' is not a pointer");
1085   return error_mark_node;
1086 }
1087
1088 /* Make an expression to refer to the COMPONENT field of
1089    structure or union value DATUM.  COMPONENT is an arbitrary
1090    expression.  DATUM has not already been checked out to be of
1091    aggregate type.
1092
1093    For C++, COMPONENT may be a TREE_LIST.  This happens when we must
1094    return an object of member type to a method of the current class,
1095    but there is not yet enough typing information to know which one.
1096    As a special case, if there is only one method by that name,
1097    it is returned.  Otherwise we return an expression which other
1098    routines will have to know how to deal with later.  */
1099
1100 tree
1101 build_m_component_ref (datum, component)
1102      tree datum, component;
1103 {
1104   tree type;
1105   tree objtype;
1106   tree field_type;
1107   int type_quals;
1108   tree binfo;
1109
1110   if (processing_template_decl)
1111     return build_min_nt (DOTSTAR_EXPR, datum, component);
1112
1113   datum = decay_conversion (datum);
1114
1115   if (datum == error_mark_node || component == error_mark_node)
1116     return error_mark_node;
1117
1118   objtype = TYPE_MAIN_VARIANT (TREE_TYPE (datum));
1119
1120   if (TYPE_PTRMEMFUNC_P (TREE_TYPE (component)))
1121     {
1122       type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (component)));
1123       field_type = type;
1124     }
1125   else if (TYPE_PTRMEM_P (TREE_TYPE (component)))
1126     {
1127       type = TREE_TYPE (TREE_TYPE (component));
1128       field_type = TREE_TYPE (type);
1129
1130       /* Compute the type of the field, as described in [expr.ref].  */
1131       type_quals = TYPE_UNQUALIFIED;
1132       if (TREE_CODE (field_type) == REFERENCE_TYPE)
1133         /* The standard says that the type of the result should be the
1134            type referred to by the reference.  But for now, at least,
1135            we do the conversion from reference type later.  */
1136         ;
1137       else
1138         {
1139           type_quals = (cp_type_quals (field_type)
1140                         | cp_type_quals (TREE_TYPE (datum)));
1141
1142           /* There's no such thing as a mutable pointer-to-member, so
1143              things are not as complex as they are for references to
1144              non-static data members.  */
1145           field_type = cp_build_qualified_type (field_type, type_quals);
1146         }
1147     }
1148   else
1149     {
1150       error ("`%E' cannot be used as a member pointer, since it is of type `%T'",
1151                 component, TREE_TYPE (component));
1152       return error_mark_node;
1153     }
1154
1155   if (! IS_AGGR_TYPE (objtype))
1156     {
1157       error ("cannot apply member pointer `%E' to `%E', which is of non-aggregate type `%T'",
1158                 component, datum, objtype);
1159       return error_mark_node;
1160     }
1161
1162   binfo = lookup_base (objtype, TYPE_METHOD_BASETYPE (type),
1163                        ba_check, NULL);
1164   if (!binfo)
1165     {
1166       error ("member type `%T::' incompatible with object type `%T'",
1167                 TYPE_METHOD_BASETYPE (type), objtype);
1168       return error_mark_node;
1169     }
1170   else if (binfo == error_mark_node)
1171     return error_mark_node;
1172
1173   component = build (OFFSET_REF, field_type, datum, component);
1174   if (TREE_CODE (type) == OFFSET_TYPE)
1175     component = resolve_offset_ref (component);
1176   return component;
1177 }
1178
1179 /* Return a tree node for the expression TYPENAME '(' PARMS ')'.  */
1180
1181 tree
1182 build_functional_cast (exp, parms)
1183      tree exp;
1184      tree parms;
1185 {
1186   /* This is either a call to a constructor,
1187      or a C cast in C++'s `functional' notation.  */
1188   tree type;
1189
1190   if (exp == error_mark_node || parms == error_mark_node)
1191     return error_mark_node;
1192
1193   if (TREE_CODE (exp) == IDENTIFIER_NODE)
1194     {
1195       if (IDENTIFIER_HAS_TYPE_VALUE (exp))
1196         /* Either an enum or an aggregate type.  */
1197         type = IDENTIFIER_TYPE_VALUE (exp);
1198       else
1199         {
1200           type = lookup_name (exp, 1);
1201           if (!type || TREE_CODE (type) != TYPE_DECL)
1202             {
1203               error ("`%T' fails to be a typedef or built-in type", exp);
1204               return error_mark_node;
1205             }
1206           type = TREE_TYPE (type);
1207         }
1208     }
1209   else if (TREE_CODE (exp) == TYPE_DECL)
1210     type = TREE_TYPE (exp);
1211   else
1212     type = exp;
1213
1214   if (processing_template_decl)
1215     return build_min (CAST_EXPR, type, parms);
1216
1217   if (! IS_AGGR_TYPE (type))
1218     {
1219       /* this must build a C cast */
1220       if (parms == NULL_TREE)
1221         parms = integer_zero_node;
1222       else
1223         {
1224           if (TREE_CHAIN (parms) != NULL_TREE)
1225             pedwarn ("initializer list being treated as compound expression");
1226           parms = build_compound_expr (parms);
1227         }
1228
1229       return build_c_cast (type, parms);
1230     }
1231
1232   /* Prepare to evaluate as a call to a constructor.  If this expression
1233      is actually used, for example,
1234
1235      return X (arg1, arg2, ...);
1236
1237      then the slot being initialized will be filled in.  */
1238
1239   if (!complete_type_or_else (type, NULL_TREE))
1240     return error_mark_node;
1241   if (abstract_virtuals_error (NULL_TREE, type))
1242     return error_mark_node;
1243
1244   if (parms && TREE_CHAIN (parms) == NULL_TREE)
1245     return build_c_cast (type, TREE_VALUE (parms));
1246
1247   /* We need to zero-initialize POD types.  Let's do that for everything
1248      that doesn't need a constructor.  */
1249   if (parms == NULL_TREE && !TYPE_NEEDS_CONSTRUCTING (type)
1250       && TYPE_HAS_DEFAULT_CONSTRUCTOR (type))
1251     {
1252       exp = build (CONSTRUCTOR, type, NULL_TREE, NULL_TREE);
1253       return get_target_expr (exp);
1254     }
1255
1256   exp = build_special_member_call (NULL_TREE, complete_ctor_identifier, parms,
1257                                    TYPE_BINFO (type), LOOKUP_NORMAL);
1258
1259   if (exp == error_mark_node)
1260     return error_mark_node;
1261
1262   return build_cplus_new (type, exp);
1263 }
1264 \f
1265
1266 /* Add new exception specifier SPEC, to the LIST we currently have.
1267    If it's already in LIST then do nothing.
1268    Moan if it's bad and we're allowed to. COMPLAIN < 0 means we
1269    know what we're doing.  */
1270
1271 tree
1272 add_exception_specifier (list, spec, complain)
1273      tree list, spec;
1274      int complain;
1275 {
1276   int ok;
1277   tree core = spec;
1278   int is_ptr;
1279   int diag_type = -1; /* none */
1280
1281   if (spec == error_mark_node)
1282     return list;
1283
1284   my_friendly_assert (spec && (!list || TREE_VALUE (list)), 19990317);
1285
1286   /* [except.spec] 1, type in an exception specifier shall not be
1287      incomplete, or pointer or ref to incomplete other than pointer
1288      to cv void.  */
1289   is_ptr = TREE_CODE (core) == POINTER_TYPE;
1290   if (is_ptr || TREE_CODE (core) == REFERENCE_TYPE)
1291     core = TREE_TYPE (core);
1292   if (complain < 0)
1293     ok = 1;
1294   else if (VOID_TYPE_P (core))
1295     ok = is_ptr;
1296   else if (TREE_CODE (core) == TEMPLATE_TYPE_PARM)
1297     ok = 1;
1298   else if (processing_template_decl)
1299     ok = 1;
1300   else
1301     {
1302       ok = 1;
1303       /* 15.4/1 says that types in an exception specifier must be complete,
1304          but it seems more reasonable to only require this on definitions
1305          and calls.  So just give a pedwarn at this point; we will give an
1306          error later if we hit one of those two cases.  */
1307       if (!COMPLETE_TYPE_P (complete_type (core)))
1308         diag_type = 2; /* pedwarn */
1309     }
1310
1311   if (ok)
1312     {
1313       tree probe;
1314
1315       for (probe = list; probe; probe = TREE_CHAIN (probe))
1316         if (same_type_p (TREE_VALUE (probe), spec))
1317           break;
1318       if (!probe)
1319         list = tree_cons (NULL_TREE, spec, list);
1320     }
1321   else
1322     diag_type = 0; /* error */
1323
1324   if (diag_type >= 0 && complain)
1325     cxx_incomplete_type_diagnostic (NULL_TREE, core, diag_type);
1326
1327   return list;
1328 }
1329
1330 /* Combine the two exceptions specifier lists LIST and ADD, and return
1331    their union.  */
1332
1333 tree
1334 merge_exception_specifiers (list, add)
1335      tree list, add;
1336 {
1337   if (!list || !add)
1338     return NULL_TREE;
1339   else if (!TREE_VALUE (list))
1340     return add;
1341   else if (!TREE_VALUE (add))
1342     return list;
1343   else
1344     {
1345       tree orig_list = list;
1346
1347       for (; add; add = TREE_CHAIN (add))
1348         {
1349           tree spec = TREE_VALUE (add);
1350           tree probe;
1351
1352           for (probe = orig_list; probe; probe = TREE_CHAIN (probe))
1353             if (same_type_p (TREE_VALUE (probe), spec))
1354               break;
1355           if (!probe)
1356             {
1357               spec = build_tree_list (NULL_TREE, spec);
1358               TREE_CHAIN (spec) = list;
1359               list = spec;
1360             }
1361         }
1362     }
1363   return list;
1364 }
1365
1366 /* Subroutine of build_call.  Ensure that each of the types in the
1367    exception specification is complete.  Technically, 15.4/1 says that
1368    they need to be complete when we see a declaration of the function,
1369    but we should be able to get away with only requiring this when the
1370    function is defined or called.  See also add_exception_specifier.  */
1371
1372 void
1373 require_complete_eh_spec_types (fntype, decl)
1374      tree fntype, decl;
1375 {
1376   tree raises;
1377   /* Don't complain about calls to op new.  */
1378   if (decl && DECL_ARTIFICIAL (decl))
1379     return;
1380   for (raises = TYPE_RAISES_EXCEPTIONS (fntype); raises;
1381        raises = TREE_CHAIN (raises))
1382     {
1383       tree type = TREE_VALUE (raises);
1384       if (type && !COMPLETE_TYPE_P (type))
1385         {
1386           if (decl)
1387             error
1388               ("call to function `%D' which throws incomplete type `%#T'",
1389                decl, type);
1390           else
1391             error ("call to function which throws incomplete type `%#T'",
1392                    decl);
1393         }
1394     }
1395 }