/* Report error messages, build initializers, and perform some front-end optimizations for C++ compiler. Copyright (C) 1987, 88, 89, 92-98, 1999 Free Software Foundation, Inc. Hacked by Michael Tiemann (tiemann@cygnus.com) This file is part of GNU CC. GNU CC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU CC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU CC; see the file COPYING. If not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* This file is part of the C++ front end. It contains routines to build C++ expressions given their operands, including computing the types of the result, C and C++ specific error checks, and some optimization. There are also routines to build RETURN_STMT nodes and CASE_STMT nodes, and to process initializations in declarations (since they work like a strange sort of assignment). */ #include "config.h" #include "system.h" #include "tree.h" #include "cp-tree.h" #include "flags.h" #include "toplev.h" #include "output.h" static tree process_init_constructor PROTO((tree, tree, tree *)); static void ack PVPROTO ((const char *, ...)) ATTRIBUTE_PRINTF_1; /* Print an error message stemming from an attempt to use BASETYPE as a base class for TYPE. */ tree error_not_base_type (basetype, type) tree basetype, type; { if (TREE_CODE (basetype) == FUNCTION_DECL) basetype = DECL_CLASS_CONTEXT (basetype); cp_error ("type `%T' is not a base type for type `%T'", basetype, type); return error_mark_node; } tree binfo_or_else (parent_or_type, type) tree parent_or_type, type; { tree binfo; if (TYPE_MAIN_VARIANT (parent_or_type) == TYPE_MAIN_VARIANT (type)) return TYPE_BINFO (parent_or_type); if ((binfo = get_binfo (parent_or_type, TYPE_MAIN_VARIANT (type), 0))) { if (binfo == error_mark_node) return NULL_TREE; return binfo; } error_not_base_type (parent_or_type, type); return NULL_TREE; } /* According to ARM $7.1.6, "A `const' object may be initialized, but its value may not be changed thereafter. Thus, we emit hard errors for these, rather than just pedwarns. If `SOFT' is 1, then we just pedwarn. (For example, conversions to references.) */ void readonly_error (arg, string, soft) tree arg; const char *string; int soft; { const char *fmt; void (*fn) PVPROTO ((const char *, ...)); if (soft) fn = cp_pedwarn; else fn = cp_error; if (TREE_CODE (arg) == COMPONENT_REF) { if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0)))) fmt = "%s of data-member `%D' in read-only structure"; else fmt = "%s of read-only data-member `%D'"; (*fn) (fmt, string, TREE_OPERAND (arg, 1)); } else if (TREE_CODE (arg) == VAR_DECL) { if (DECL_LANG_SPECIFIC (arg) && DECL_IN_AGGR_P (arg) && !TREE_STATIC (arg)) fmt = "%s of constant field `%D'"; else fmt = "%s of read-only variable `%D'"; (*fn) (fmt, string, arg); } else if (TREE_CODE (arg) == PARM_DECL) (*fn) ("%s of read-only parameter `%D'", string, arg); else if (TREE_CODE (arg) == INDIRECT_REF && TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0))) == REFERENCE_TYPE && (TREE_CODE (TREE_OPERAND (arg, 0)) == VAR_DECL || TREE_CODE (TREE_OPERAND (arg, 0)) == PARM_DECL)) (*fn) ("%s of read-only reference `%D'", string, TREE_OPERAND (arg, 0)); else if (TREE_CODE (arg) == RESULT_DECL) (*fn) ("%s of read-only named return value `%D'", string, arg); else if (TREE_CODE (arg) == FUNCTION_DECL) (*fn) ("%s of function `%D'", string, arg); else (*fn) ("%s of read-only location", string); } /* If TYPE has abstract virtual functions, issue an error about trying to create an object of that type. DECL is the object declared, or NULL_TREE if the declaration is unavailable. Returns 1 if an error occurred; zero if all was well. */ int abstract_virtuals_error (decl, type) tree decl; tree type; { tree u; tree tu; if (!CLASS_TYPE_P (type) || !CLASSTYPE_PURE_VIRTUALS (type)) return 0; u = CLASSTYPE_PURE_VIRTUALS (type); if (decl) { if (TREE_CODE (decl) == RESULT_DECL) return 0; if (TREE_CODE (decl) == VAR_DECL) cp_error ("cannot declare variable `%D' to be of type `%T'", decl, type); else if (TREE_CODE (decl) == PARM_DECL) cp_error ("cannot declare parameter `%D' to be of type `%T'", decl, type); else if (TREE_CODE (decl) == FIELD_DECL) cp_error ("cannot declare field `%D' to be of type `%T'", decl, type); else if (TREE_CODE (decl) == FUNCTION_DECL && TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE) cp_error ("invalid return type for member function `%#D'", decl); else if (TREE_CODE (decl) == FUNCTION_DECL) cp_error ("invalid return type for function `%#D'", decl); } else cp_error ("cannot allocate an object of type `%T'", type); /* Only go through this once. */ if (TREE_PURPOSE (u) == NULL_TREE) { TREE_PURPOSE (u) = error_mark_node; error (" since the following virtual functions are abstract:"); for (tu = u; tu; tu = TREE_CHAIN (tu)) cp_error_at ("\t%#D", TREE_VALUE (tu)); } else cp_error (" since type `%T' has abstract virtual functions", type); return 1; } /* Print an error message for invalid use of an incomplete type. VALUE is the expression that was used (or 0 if that isn't known) and TYPE is the type that was invalid. */ void incomplete_type_error (value, type) tree value; tree type; { /* Avoid duplicate error message. */ if (TREE_CODE (type) == ERROR_MARK) return; retry: /* We must print an error message. Be clever about what it says. */ switch (TREE_CODE (type)) { case RECORD_TYPE: case UNION_TYPE: case ENUMERAL_TYPE: cp_error_at ("invalid use of a forward-declared, but not defined type `%#T'", type); break; case VOID_TYPE: cp_error ("invalid use of void expression"); break; case ARRAY_TYPE: if (TYPE_DOMAIN (type)) { type = TREE_TYPE (type); goto retry; } cp_error ("invalid use of array with unspecified bounds"); break; case OFFSET_TYPE: bad_member: cp_error ("invalid use of member (did you forget the `&' ?)"); break; case TEMPLATE_TYPE_PARM: cp_error ("invalid use of template type parameter"); break; case UNKNOWN_TYPE: if (value && TREE_CODE (value) == COMPONENT_REF) goto bad_member; else if (value && TREE_CODE (value) == ADDR_EXPR) cp_error ("address of overloaded function with no contextual type information"); else if (value && TREE_CODE (value) == OVERLOAD) cp_error ("overloaded function with no contextual type information"); else cp_error ("insufficient contextual information to determine type"); break; default: my_friendly_abort (108); } if (value != 0 && (TREE_CODE (value) == VAR_DECL || TREE_CODE (value) == PARM_DECL)) cp_error_at ("incomplete `%D' defined here", value); } /* Like error(), but don't call report_error_function(). */ static void ack VPROTO ((const char *msg, ...)) { #ifndef ANSI_PROTOTYPES const char *msg; #endif va_list ap; VA_START (ap, msg); #ifndef ANSI_PROTOTYPES msg = va_arg (ap, const char *); #endif if (input_filename) fprintf (stderr, "%s:%d: ", input_filename, lineno); else fprintf (stderr, "%s: ", progname); vfprintf (stderr, msg, ap); va_end (ap); fprintf (stderr, "\n"); } /* There are times when the compiler can get very confused, confused to the point of giving up by aborting, simply because of previous input errors. It is much better to have the user go back and correct those errors first, and see if it makes us happier, than it is to abort on him. This is because when one has a 10,000 line program, and the compiler comes back with ``core dump'', the user is left not knowing even where to begin to fix things and no place to even try and work around things. The parameter is to uniquely identify the problem to the user, so that they can say, I am having problem 59, and know that fix 7 will probably solve their problem. Or, we can document what problem 59 is, so they can understand how to work around it, should they ever run into it. We used to tell people to "fix the above error[s] and try recompiling the program" via a call to fatal, but that message tended to look silly. So instead, we just do the equivalent of a call to fatal in the same situation (call exit). We used to assign sequential numbers for the aborts; now we use an encoding of the date the abort was added, since that has more meaning when we only see the error message. */ static int abortcount = 0; void my_friendly_abort (i) int i; { /* if the previous error came through here, i.e. report_error_function ended up calling us again, don't just exit; we want a diagnostic of some kind. */ if (abortcount == 1) current_function_decl = NULL_TREE; else if (errorcount > 0 || sorrycount > 0) { if (abortcount > 1) { if (i == 0) ack ("Internal compiler error."); else ack ("Internal compiler error %d.", i); ack ("Please submit a full bug report."); ack ("See for instructions."); } else error ("confused by earlier errors, bailing out"); exit (34); } ++abortcount; if (i == 0) error ("Internal compiler error."); else error ("Internal compiler error %d.", i); error ("Please submit a full bug report."); fatal ("See for instructions."); } void my_friendly_assert (cond, where) int cond, where; { if (cond == 0) my_friendly_abort (where); } /* Perform appropriate conversions on the initial value of a variable, store it in the declaration DECL, and print any error messages that are appropriate. If the init is invalid, store an ERROR_MARK. C++: Note that INIT might be a TREE_LIST, which would mean that it is a base class initializer for some aggregate type, hopefully compatible with DECL. If INIT is a single element, and DECL is an aggregate type, we silently convert INIT into a TREE_LIST, allowing a constructor to be called. If INIT is a TREE_LIST and there is no constructor, turn INIT into a CONSTRUCTOR and use standard initialization techniques. Perhaps a warning should be generated? Returns value of initializer if initialization could not be performed for static variable. In that case, caller must do the storing. */ tree store_init_value (decl, init) tree decl, init; { register tree value, type; /* If variable's type was invalidly declared, just ignore it. */ type = TREE_TYPE (decl); if (TREE_CODE (type) == ERROR_MARK) return NULL_TREE; #if 0 /* This breaks arrays, and should not have any effect for other decls. */ /* Take care of C++ business up here. */ type = TYPE_MAIN_VARIANT (type); #endif if (IS_AGGR_TYPE (type)) { if (! TYPE_HAS_TRIVIAL_INIT_REF (type) && TREE_CODE (init) != CONSTRUCTOR) my_friendly_abort (109); if (TREE_CODE (init) == TREE_LIST) { cp_error ("constructor syntax used, but no constructor declared for type `%T'", type); init = build_nt (CONSTRUCTOR, NULL_TREE, nreverse (init)); } #if 0 if (TREE_CODE (init) == CONSTRUCTOR) { tree field; /* Check that we're really an aggregate as ARM 8.4.1 defines it. */ if (CLASSTYPE_N_BASECLASSES (type)) cp_error_at ("initializer list construction invalid for derived class object `%D'", decl); if (CLASSTYPE_VTBL_PTR (type)) cp_error_at ("initializer list construction invalid for polymorphic class object `%D'", decl); if (TYPE_NEEDS_CONSTRUCTING (type)) { cp_error_at ("initializer list construction invalid for `%D'", decl); error ("due to the presence of a constructor"); } for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) if (TREE_PRIVATE (field) || TREE_PROTECTED (field)) { cp_error_at ("initializer list construction invalid for `%D'", decl); cp_error_at ("due to non-public access of member `%D'", field); } for (field = TYPE_METHODS (type); field; field = TREE_CHAIN (field)) if (TREE_PRIVATE (field) || TREE_PROTECTED (field)) { cp_error_at ("initializer list construction invalid for `%D'", decl); cp_error_at ("due to non-public access of member `%D'", field); } } #endif } else if (TREE_CODE (init) == TREE_LIST && TREE_TYPE (init) != unknown_type_node) { if (TREE_CODE (decl) == RESULT_DECL) { if (TREE_CHAIN (init)) { warning ("comma expression used to initialize return value"); init = build_compound_expr (init); } else init = TREE_VALUE (init); } else if (TREE_CODE (init) == TREE_LIST && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE) { error ("cannot initialize arrays using this syntax"); return NULL_TREE; } else { /* We get here with code like `int a (2);' */ if (TREE_CHAIN (init) != NULL_TREE) { pedwarn ("initializer list being treated as compound expression"); init = build_compound_expr (init); } else init = TREE_VALUE (init); } } /* End of special C++ code. */ /* Digest the specified initializer into an expression. */ value = digest_init (type, init, (tree *) 0); /* Store the expression if valid; else report error. */ if (TREE_CODE (value) == ERROR_MARK) ; /* Other code expects that initializers for objects of types that need constructing never make it into DECL_INITIAL, and passes 'init' to build_aggr_init without checking DECL_INITIAL. So just return. */ else if (TYPE_NEEDS_CONSTRUCTING (type)) return value; else if (TREE_STATIC (decl) && (! TREE_CONSTANT (value) || ! initializer_constant_valid_p (value, TREE_TYPE (value)) #if 0 /* A STATIC PUBLIC int variable doesn't have to be run time inited when doing pic. (mrs) */ /* Since ctors and dtors are the only things that can reference vtables, and they are always written down the vtable definition, we can leave the vtables in initialized data space. However, other initialized data cannot be initialized this way. Instead a global file-level initializer must do the job. */ || (flag_pic && !DECL_VIRTUAL_P (decl) && TREE_PUBLIC (decl)) #endif )) return value; #if 0 /* No, that's C. jason 9/19/94 */ else { if (pedantic && TREE_CODE (value) == CONSTRUCTOR) { if (! TREE_CONSTANT (value) || ! TREE_STATIC (value)) pedwarn ("ANSI C++ forbids non-constant aggregate initializer expressions"); } } #endif /* Store the VALUE in DECL_INITIAL. If we're building a statement-tree we will actually expand the initialization later when we output this function. */ DECL_INITIAL (decl) = value; return NULL_TREE; } /* Digest the parser output INIT as an initializer for type TYPE. Return a C expression of type TYPE to represent the initial value. If TAIL is nonzero, it points to a variable holding a list of elements of which INIT is the first. We update the list stored there by removing from the head all the elements that we use. Normally this is only one; we use more than one element only if TYPE is an aggregate and INIT is not a constructor. */ tree digest_init (type, init, tail) tree type, init, *tail; { enum tree_code code = TREE_CODE (type); tree element = NULL_TREE; tree old_tail_contents = NULL_TREE; /* Nonzero if INIT is a braced grouping, which comes in as a CONSTRUCTOR tree node which has no TREE_TYPE. */ int raw_constructor; /* By default, assume we use one element from a list. We correct this later in the sole case where it is not true. */ if (tail) { old_tail_contents = *tail; *tail = TREE_CHAIN (*tail); } if (init == error_mark_node || (TREE_CODE (init) == TREE_LIST && TREE_VALUE (init) == error_mark_node)) return error_mark_node; /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ if (TREE_CODE (init) == NON_LVALUE_EXPR) init = TREE_OPERAND (init, 0); if (TREE_CODE (init) == CONSTRUCTOR && TREE_TYPE (init) == type) return init; raw_constructor = TREE_CODE (init) == CONSTRUCTOR && TREE_TYPE (init) == 0; if (raw_constructor && CONSTRUCTOR_ELTS (init) != 0 && TREE_CHAIN (CONSTRUCTOR_ELTS (init)) == 0) { element = TREE_VALUE (CONSTRUCTOR_ELTS (init)); /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ if (element && TREE_CODE (element) == NON_LVALUE_EXPR) element = TREE_OPERAND (element, 0); if (element == error_mark_node) return element; } /* Initialization of an array of chars from a string constant optionally enclosed in braces. */ if (code == ARRAY_TYPE) { tree typ1; if (TREE_CODE (init) == TREE_LIST) { error ("initializing array with parameter list"); return error_mark_node; } typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type)); if ((typ1 == char_type_node || typ1 == signed_char_type_node || typ1 == unsigned_char_type_node || typ1 == unsigned_wchar_type_node || typ1 == signed_wchar_type_node) && ((init && TREE_CODE (init) == STRING_CST) || (element && TREE_CODE (element) == STRING_CST))) { tree string = element ? element : init; if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (string))) != char_type_node) && TYPE_PRECISION (typ1) == BITS_PER_UNIT) { error ("char-array initialized from wide string"); return error_mark_node; } if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (string))) == char_type_node) && TYPE_PRECISION (typ1) != BITS_PER_UNIT) { error ("int-array initialized from non-wide string"); return error_mark_node; } TREE_TYPE (string) = type; if (TYPE_DOMAIN (type) != 0 && TREE_CONSTANT (TYPE_SIZE (type))) { register int size = TREE_INT_CST_LOW (TYPE_SIZE (type)); size = (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT; /* In C it is ok to subtract 1 from the length of the string because it's ok to ignore the terminating null char that is counted in the length of the constant, but in C++ this would be invalid. */ if (size < TREE_STRING_LENGTH (string)) pedwarn ("initializer-string for array of chars is too long"); } return string; } } /* Handle scalar types, including conversions, and signature pointers and references. */ if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE || code == ENUMERAL_TYPE || code == REFERENCE_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE || TYPE_PTRMEMFUNC_P (type)) { if (raw_constructor) { if (element == 0) { error ("initializer for scalar variable requires one element"); return error_mark_node; } init = element; } while (TREE_CODE (init) == CONSTRUCTOR && TREE_HAS_CONSTRUCTOR (init)) { cp_pedwarn ("braces around scalar initializer for `%T'", type); init = CONSTRUCTOR_ELTS (init); if (TREE_CHAIN (init)) cp_pedwarn ("ignoring extra initializers for `%T'", type); init = TREE_VALUE (init); } return convert_for_initialization (0, type, init, LOOKUP_NORMAL, "initialization", NULL_TREE, 0); } /* Come here only for records and arrays (and unions with constructors). */ if (TYPE_SIZE (type) && ! TREE_CONSTANT (TYPE_SIZE (type))) { cp_error ("variable-sized object of type `%T' may not be initialized", type); return error_mark_node; } if (code == ARRAY_TYPE || IS_AGGR_TYPE_CODE (code)) { if (raw_constructor && TYPE_NON_AGGREGATE_CLASS (type)) { cp_error ("subobject of type `%T' must be initialized by constructor, not by `%E'", type, init); return error_mark_node; } else if (raw_constructor) return process_init_constructor (type, init, (tree *)0); else if (can_convert_arg (type, TREE_TYPE (init), init) || TYPE_NON_AGGREGATE_CLASS (type)) /* These are never initialized from multiple constructor elements. */; else if (tail != 0) { *tail = old_tail_contents; return process_init_constructor (type, 0, tail); } if (code != ARRAY_TYPE) { int flags = LOOKUP_NORMAL; /* Initialization from { } is copy-initialization. */ if (tail) flags |= LOOKUP_ONLYCONVERTING; return convert_for_initialization (NULL_TREE, type, init, flags, "initialization", NULL_TREE, 0); } } error ("invalid initializer"); return error_mark_node; } /* Process a constructor for a variable of type TYPE. The constructor elements may be specified either with INIT or with ELTS, only one of which should be non-null. If INIT is specified, it is a CONSTRUCTOR node which is specifically and solely for initializing this datum. If ELTS is specified, it is the address of a variable containing a list of expressions. We take as many elements as we need from the head of the list and update the list. In the resulting constructor, TREE_CONSTANT is set if all elts are constant, and TREE_STATIC is set if, in addition, all elts are simple enough constants that the assembler and linker can compute them. */ static tree process_init_constructor (type, init, elts) tree type, init, *elts; { register tree tail; /* List of the elements of the result constructor, in reverse order. */ register tree members = NULL; register tree next1; tree result; int allconstant = 1; int allsimple = 1; int erroneous = 0; /* Make TAIL be the list of elements to use for the initialization, no matter how the data was given to us. */ if (elts) { if (warn_missing_braces) warning ("aggregate has a partly bracketed initializer"); tail = *elts; } else tail = CONSTRUCTOR_ELTS (init); /* Gobble as many elements as needed, and make a constructor or initial value for each element of this aggregate. Chain them together in result. If there are too few, use 0 for each scalar ultimate component. */ if (TREE_CODE (type) == ARRAY_TYPE) { tree domain = TYPE_DOMAIN (type); register long len; register int i; if (domain) len = (TREE_INT_CST_LOW (TYPE_MAX_VALUE (domain)) - TREE_INT_CST_LOW (TYPE_MIN_VALUE (domain)) + 1); else len = -1; /* Take as many as there are */ for (i = 0; len < 0 || i < len; i++) { if (tail) { if (TREE_PURPOSE (tail) && (TREE_CODE (TREE_PURPOSE (tail)) != INTEGER_CST || TREE_INT_CST_LOW (TREE_PURPOSE (tail)) != i)) sorry ("non-trivial labeled initializers"); if (TREE_VALUE (tail) != 0) { tree tail1 = tail; next1 = digest_init (TREE_TYPE (type), TREE_VALUE (tail), &tail1); if (next1 == error_mark_node) return next1; my_friendly_assert (same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (type)), TYPE_MAIN_VARIANT (TREE_TYPE (next1))), 981123); my_friendly_assert (tail1 == 0 || TREE_CODE (tail1) == TREE_LIST, 319); if (tail == tail1 && len < 0) { error ("non-empty initializer for array of empty elements"); /* Just ignore what we were supposed to use. */ tail1 = NULL_TREE; } tail = tail1; } else { next1 = error_mark_node; tail = TREE_CHAIN (tail); } } else if (len < 0) /* We're done. */ break; else if (TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (type))) { /* If this type needs constructors run for default-initialization, we can't rely on the backend to do it for us, so build up TARGET_EXPRs. If the type in question is a class, just build one up; if it's an array, recurse. */ if (IS_AGGR_TYPE (TREE_TYPE (type))) next1 = build_functional_cast (TREE_TYPE (type), NULL_TREE); else next1 = build (CONSTRUCTOR, NULL_TREE, NULL_TREE, NULL_TREE); next1 = digest_init (TREE_TYPE (type), next1, 0); } else /* The default zero-initialization is fine for us; don't add anything to the CONSTRUCTOR. */ break; if (next1 == error_mark_node) erroneous = 1; else if (!TREE_CONSTANT (next1)) allconstant = 0; else if (! initializer_constant_valid_p (next1, TREE_TYPE (next1))) allsimple = 0; members = expr_tree_cons (NULL_TREE, next1, members); } } else if (TREE_CODE (type) == RECORD_TYPE) { register tree field; if (tail) { if (TYPE_USES_VIRTUAL_BASECLASSES (type)) { sorry ("initializer list for object of class with virtual base classes"); return error_mark_node; } if (TYPE_BINFO_BASETYPES (type)) { sorry ("initializer list for object of class with base classes"); return error_mark_node; } if (TYPE_POLYMORPHIC_P (type)) { sorry ("initializer list for object using virtual functions"); return error_mark_node; } } for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) { if (! DECL_NAME (field) && DECL_C_BIT_FIELD (field)) { members = expr_tree_cons (field, integer_zero_node, members); continue; } if (TREE_CODE (field) != FIELD_DECL) continue; if (tail) { if (TREE_PURPOSE (tail) && TREE_PURPOSE (tail) != field && TREE_PURPOSE (tail) != DECL_NAME (field)) sorry ("non-trivial labeled initializers"); if (TREE_VALUE (tail) != 0) { tree tail1 = tail; next1 = digest_init (TREE_TYPE (field), TREE_VALUE (tail), &tail1); my_friendly_assert (tail1 == 0 || TREE_CODE (tail1) == TREE_LIST, 320); tail = tail1; } else { next1 = error_mark_node; tail = TREE_CHAIN (tail); } } else if (TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (field))) { /* If this type needs constructors run for default-initialization, we can't rely on the backend to do it for us, so build up TARGET_EXPRs. If the type in question is a class, just build one up; if it's an array, recurse. */ if (IS_AGGR_TYPE (TREE_TYPE (field))) next1 = build_functional_cast (TREE_TYPE (field), NULL_TREE); else next1 = build (CONSTRUCTOR, NULL_TREE, NULL_TREE, NULL_TREE); next1 = digest_init (TREE_TYPE (field), next1, 0); /* Warn when some struct elements are implicitly initialized. */ if (extra_warnings) cp_warning ("missing initializer for member `%D'", field); } else { if (TREE_READONLY (field)) cp_error ("uninitialized const member `%D'", field); else if (TYPE_LANG_SPECIFIC (TREE_TYPE (field)) && CLASSTYPE_READONLY_FIELDS_NEED_INIT (TREE_TYPE (field))) cp_error ("member `%D' with uninitialized const fields", field); else if (TREE_CODE (TREE_TYPE (field)) == REFERENCE_TYPE) cp_error ("member `%D' is uninitialized reference", field); /* Warn when some struct elements are implicitly initialized to zero. */ if (extra_warnings) cp_warning ("missing initializer for member `%D'", field); /* The default zero-initialization is fine for us; don't add anything to the CONSTRUCTOR. */ continue; } if (next1 == error_mark_node) erroneous = 1; else if (!TREE_CONSTANT (next1)) allconstant = 0; else if (! initializer_constant_valid_p (next1, TREE_TYPE (next1))) allsimple = 0; members = expr_tree_cons (field, next1, members); } } else if (TREE_CODE (type) == UNION_TYPE /* If the initializer was empty, use default zero initialization. */ && tail) { register tree field = TYPE_FIELDS (type); /* Find the first named field. ANSI decided in September 1990 that only named fields count here. */ while (field && (DECL_NAME (field) == 0 || TREE_CODE (field) != FIELD_DECL)) field = TREE_CHAIN (field); /* If this element specifies a field, initialize via that field. */ if (TREE_PURPOSE (tail) != NULL_TREE) { int win = 0; if (TREE_CODE (TREE_PURPOSE (tail)) == FIELD_DECL) /* Handle the case of a call by build_c_cast. */ field = TREE_PURPOSE (tail), win = 1; else if (TREE_CODE (TREE_PURPOSE (tail)) != IDENTIFIER_NODE) error ("index value instead of field name in union initializer"); else { tree temp; for (temp = TYPE_FIELDS (type); temp; temp = TREE_CHAIN (temp)) if (DECL_NAME (temp) == TREE_PURPOSE (tail)) break; if (temp) field = temp, win = 1; else cp_error ("no field `%D' in union being initialized", TREE_PURPOSE (tail)); } if (!win) TREE_VALUE (tail) = error_mark_node; } else if (field == 0) { cp_error ("union `%T' with no named members cannot be initialized", type); TREE_VALUE (tail) = error_mark_node; } if (TREE_VALUE (tail) != 0) { tree tail1 = tail; next1 = digest_init (TREE_TYPE (field), TREE_VALUE (tail), &tail1); if (tail1 != 0 && TREE_CODE (tail1) != TREE_LIST) my_friendly_abort (357); tail = tail1; } else { next1 = error_mark_node; tail = TREE_CHAIN (tail); } if (next1 == error_mark_node) erroneous = 1; else if (!TREE_CONSTANT (next1)) allconstant = 0; else if (initializer_constant_valid_p (next1, TREE_TYPE (next1)) == 0) allsimple = 0; members = expr_tree_cons (field, next1, members); } /* If arguments were specified as a list, just remove the ones we used. */ if (elts) *elts = tail; /* If arguments were specified as a constructor, complain unless we used all the elements of the constructor. */ else if (tail) pedwarn ("excess elements in aggregate initializer"); if (erroneous) return error_mark_node; result = build (CONSTRUCTOR, type, NULL_TREE, nreverse (members)); if (init) TREE_HAS_CONSTRUCTOR (result) = TREE_HAS_CONSTRUCTOR (init); if (allconstant) TREE_CONSTANT (result) = 1; if (allconstant && allsimple) TREE_STATIC (result) = 1; return result; } /* Given a structure or union value DATUM, construct and return the structure or union component which results from narrowing that value by the type specified in BASETYPE. For example, given the hierarchy class L { int ii; }; class A : L { ... }; class B : L { ... }; class C : A, B { ... }; and the declaration C x; then the expression x.A::ii refers to the ii member of the L part of the A part of the C object named by X. In this case, DATUM would be x, and BASETYPE would be A. */ tree build_scoped_ref (datum, basetype) tree datum; tree basetype; { tree ref; tree type = TREE_TYPE (datum); if (datum == error_mark_node) return error_mark_node; if (TREE_CODE (type) == REFERENCE_TYPE) type = TREE_TYPE (type); type = TYPE_MAIN_VARIANT (type); /* This is an easy conversion. */ if (is_aggr_type (basetype, 1)) { tree binfo = TYPE_BINFO (basetype); if (binfo != TYPE_BINFO (type)) { binfo = get_binfo (binfo, type, 1); if (binfo == error_mark_node) return error_mark_node; if (binfo == 0) return error_not_base_type (basetype, type); } switch (TREE_CODE (datum)) { case NOP_EXPR: case CONVERT_EXPR: case FLOAT_EXPR: case FIX_TRUNC_EXPR: case FIX_FLOOR_EXPR: case FIX_ROUND_EXPR: case FIX_CEIL_EXPR: ref = convert_pointer_to (binfo, build_unary_op (ADDR_EXPR, TREE_OPERAND (datum, 0), 0)); break; default: ref = convert_pointer_to (binfo, build_unary_op (ADDR_EXPR, datum, 0)); } return build_indirect_ref (ref, "(compiler error in build_scoped_ref)"); } return error_mark_node; } /* Build a reference to an object specified by the C++ `->' operator. Usually this just involves dereferencing the object, but if the `->' operator is overloaded, then such overloads must be performed until an object which does not have the `->' operator overloaded is found. An error is reported when circular pointer delegation is detected. */ tree build_x_arrow (datum) tree datum; { tree types_memoized = NULL_TREE; register tree rval = datum; tree type = TREE_TYPE (rval); tree last_rval = NULL_TREE; if (type == error_mark_node) return error_mark_node; if (processing_template_decl) return build_min_nt (ARROW_EXPR, rval); if (TREE_CODE (rval) == OFFSET_REF) { rval = resolve_offset_ref (datum); type = TREE_TYPE (rval); } if (TREE_CODE (type) == REFERENCE_TYPE) { rval = convert_from_reference (rval); type = TREE_TYPE (rval); } if (IS_AGGR_TYPE (type)) { while ((rval = build_opfncall (COMPONENT_REF, LOOKUP_NORMAL, rval, NULL_TREE, NULL_TREE))) { if (rval == error_mark_node) return error_mark_node; if (value_member (TREE_TYPE (rval), types_memoized)) { error ("circular pointer delegation detected"); return error_mark_node; } else { types_memoized = tree_cons (NULL_TREE, TREE_TYPE (rval), types_memoized); } last_rval = rval; } if (last_rval == NULL_TREE) { cp_error ("base operand of `->' has non-pointer type `%T'", type); return error_mark_node; } if (TREE_CODE (TREE_TYPE (last_rval)) == REFERENCE_TYPE) last_rval = convert_from_reference (last_rval); } else last_rval = default_conversion (rval); if (TREE_CODE (TREE_TYPE (last_rval)) == POINTER_TYPE) return build_indirect_ref (last_rval, NULL_PTR); if (types_memoized) error ("result of `operator->()' yields non-pointer result"); else error ("base operand of `->' is not a pointer"); return error_mark_node; } /* Make an expression to refer to the COMPONENT field of structure or union value DATUM. COMPONENT is an arbitrary expression. DATUM has not already been checked out to be of aggregate type. For C++, COMPONENT may be a TREE_LIST. This happens when we must return an object of member type to a method of the current class, but there is not yet enough typing information to know which one. As a special case, if there is only one method by that name, it is returned. Otherwise we return an expression which other routines will have to know how to deal with later. */ tree build_m_component_ref (datum, component) tree datum, component; { tree type; tree objtype = TREE_TYPE (datum); tree rettype; tree binfo; if (processing_template_decl) return build_min_nt (DOTSTAR_EXPR, datum, component); if (TYPE_PTRMEMFUNC_P (TREE_TYPE (component))) { type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (component))); rettype = type; } else { type = TREE_TYPE (TREE_TYPE (component)); rettype = TREE_TYPE (type); } if (datum == error_mark_node || component == error_mark_node) return error_mark_node; if (TREE_CODE (type) != OFFSET_TYPE && TREE_CODE (type) != METHOD_TYPE) { cp_error ("`%E' cannot be used as a member pointer, since it is of type `%T'", component, type); return error_mark_node; } if (TREE_CODE (objtype) == REFERENCE_TYPE) objtype = TREE_TYPE (objtype); objtype = TYPE_MAIN_VARIANT (objtype); if (! IS_AGGR_TYPE (objtype)) { cp_error ("cannot apply member pointer `%E' to `%E'", component, datum); cp_error ("which is of non-aggregate type `%T'", objtype); return error_mark_node; } binfo = get_binfo (TYPE_METHOD_BASETYPE (type), objtype, 1); if (binfo == NULL_TREE) { cp_error ("member type `%T::' incompatible with object type `%T'", TYPE_METHOD_BASETYPE (type), objtype); return error_mark_node; } else if (binfo == error_mark_node) return error_mark_node; component = build (OFFSET_REF, rettype, datum, component); if (TREE_CODE (type) == OFFSET_TYPE) component = resolve_offset_ref (component); return component; } /* Return a tree node for the expression TYPENAME '(' PARMS ')'. */ tree build_functional_cast (exp, parms) tree exp; tree parms; { /* This is either a call to a constructor, or a C cast in C++'s `functional' notation. */ tree type; if (exp == error_mark_node || parms == error_mark_node) return error_mark_node; if (TREE_CODE (exp) == IDENTIFIER_NODE) { if (IDENTIFIER_HAS_TYPE_VALUE (exp)) /* Either an enum or an aggregate type. */ type = IDENTIFIER_TYPE_VALUE (exp); else { type = lookup_name (exp, 1); if (!type || TREE_CODE (type) != TYPE_DECL) { cp_error ("`%T' fails to be a typedef or built-in type", exp); return error_mark_node; } type = TREE_TYPE (type); } } else if (TREE_CODE (exp) == TYPE_DECL) type = TREE_TYPE (exp); else type = exp; if (processing_template_decl) return build_min (CAST_EXPR, type, parms); if (! IS_AGGR_TYPE (type)) { /* this must build a C cast */ if (parms == NULL_TREE) parms = integer_zero_node; else { if (TREE_CHAIN (parms) != NULL_TREE) pedwarn ("initializer list being treated as compound expression"); parms = build_compound_expr (parms); } return build_c_cast (type, parms); } /* Prepare to evaluate as a call to a constructor. If this expression is actually used, for example, return X (arg1, arg2, ...); then the slot being initialized will be filled in. */ if (TYPE_SIZE (complete_type (type)) == NULL_TREE) { cp_error ("type `%T' is not yet defined", type); return error_mark_node; } if (abstract_virtuals_error (NULL_TREE, type)) return error_mark_node; if (parms && TREE_CHAIN (parms) == NULL_TREE) return build_c_cast (type, TREE_VALUE (parms)); /* We need to zero-initialize POD types. Let's do that for everything that doesn't need a constructor. */ if (parms == NULL_TREE && !TYPE_NEEDS_CONSTRUCTING (type) && TYPE_HAS_DEFAULT_CONSTRUCTOR (type)) { exp = build (CONSTRUCTOR, type, NULL_TREE, NULL_TREE); return get_target_expr (exp); } exp = build_method_call (NULL_TREE, ctor_identifier, parms, TYPE_BINFO (type), LOOKUP_NORMAL); if (exp == error_mark_node) return error_mark_node; return build_cplus_new (type, exp); } /* Return the character string for the name that encodes the enumeral value VALUE in the domain TYPE. */ char * enum_name_string (value, type) tree value; tree type; { register tree values = TYPE_VALUES (type); register HOST_WIDE_INT intval = TREE_INT_CST_LOW (value); my_friendly_assert (TREE_CODE (type) == ENUMERAL_TYPE, 324); while (values && TREE_INT_CST_LOW (TREE_VALUE (values)) != intval) values = TREE_CHAIN (values); if (values == NULL_TREE) { char *buf = (char *)oballoc (16 + TYPE_NAME_LENGTH (type)); /* Value must have been cast. */ sprintf (buf, "(enum %s)%ld", TYPE_NAME_STRING (type), (long) intval); return buf; } return IDENTIFIER_POINTER (TREE_PURPOSE (values)); } #if 0 /* Print out a language-specific error message for (Pascal) case or (C) switch statements. CODE tells what sort of message to print. TYPE is the type of the switch index expression. NEW is the new value that we were trying to add. OLD is the old value that stopped us from adding it. */ void report_case_error (code, type, new_value, old_value) int code; tree type; tree new_value, old_value; { if (code == 1) { if (new_value) error ("case label not within a switch statement"); else error ("default label not within a switch statement"); } else if (code == 2) { if (new_value == 0) { error ("multiple default labels in one switch"); return; } if (TREE_CODE (new_value) == RANGE_EXPR) if (TREE_CODE (old_value) == RANGE_EXPR) { char *buf = (char *)alloca (4 * (8 + TYPE_NAME_LENGTH (type))); if (TREE_CODE (type) == ENUMERAL_TYPE) sprintf (buf, "overlapping ranges [%s..%s], [%s..%s] in case expression", enum_name_string (TREE_OPERAND (new_value, 0), type), enum_name_string (TREE_OPERAND (new_value, 1), type), enum_name_string (TREE_OPERAND (old_value, 0), type), enum_name_string (TREE_OPERAND (old_value, 1), type)); else sprintf (buf, "overlapping ranges [%d..%d], [%d..%d] in case expression", TREE_INT_CST_LOW (TREE_OPERAND (new_value, 0)), TREE_INT_CST_LOW (TREE_OPERAND (new_value, 1)), TREE_INT_CST_LOW (TREE_OPERAND (old_value, 0)), TREE_INT_CST_LOW (TREE_OPERAND (old_value, 1))); error (buf); } else { char *buf = (char *)alloca (4 * (8 + TYPE_NAME_LENGTH (type))); if (TREE_CODE (type) == ENUMERAL_TYPE) sprintf (buf, "range [%s..%s] includes element `%s' in case expression", enum_name_string (TREE_OPERAND (new_value, 0), type), enum_name_string (TREE_OPERAND (new_value, 1), type), enum_name_string (old_value, type)); else sprintf (buf, "range [%d..%d] includes (%d) in case expression", TREE_INT_CST_LOW (TREE_OPERAND (new_value, 0)), TREE_INT_CST_LOW (TREE_OPERAND (new_value, 1)), TREE_INT_CST_LOW (old_value)); error (buf); } else if (TREE_CODE (old_value) == RANGE_EXPR) { char *buf = (char *)alloca (4 * (8 + TYPE_NAME_LENGTH (type))); if (TREE_CODE (type) == ENUMERAL_TYPE) sprintf (buf, "range [%s..%s] includes element `%s' in case expression", enum_name_string (TREE_OPERAND (old_value, 0), type), enum_name_string (TREE_OPERAND (old_value, 1), type), enum_name_string (new_value, type)); else sprintf (buf, "range [%d..%d] includes (%d) in case expression", TREE_INT_CST_LOW (TREE_OPERAND (old_value, 0)), TREE_INT_CST_LOW (TREE_OPERAND (old_value, 1)), TREE_INT_CST_LOW (new_value)); error (buf); } else { if (TREE_CODE (type) == ENUMERAL_TYPE) error ("duplicate label `%s' in switch statement", enum_name_string (new_value, type)); else error ("duplicate label (%d) in switch statement", TREE_INT_CST_LOW (new_value)); } } else if (code == 3) { if (TREE_CODE (type) == ENUMERAL_TYPE) warning ("case value out of range for enum %s", TYPE_NAME_STRING (type)); else warning ("case value out of range"); } else if (code == 4) { if (TREE_CODE (type) == ENUMERAL_TYPE) error ("range values `%s' and `%s' reversed", enum_name_string (new_value, type), enum_name_string (old_value, type)); else error ("range values reversed"); } } #endif /* Complain about defining new types in inappropriate places. We give an exception for C-style casts, to accommodate GNU C stylings. */ void check_for_new_type (string, inptree) const char *string; flagged_type_tree inptree; { if (inptree.new_type_flag && (pedantic || strcmp (string, "cast") != 0)) pedwarn ("ISO C++ forbids defining types within %s",string); } /* Add new exception specifier SPEC, to the LIST we currently have. If it's already in LIST then do nothing. Moan if it's bad and we're allowed to. COMPLAIN < 0 means we know what we're doing. */ tree add_exception_specifier (list, spec, complain) tree list, spec; int complain; { int ok; tree core = spec; int is_ptr; if (spec == error_mark_node) return list; my_friendly_assert (spec && (!list || TREE_VALUE (list)), 19990317); /* [except.spec] 1, type in an exception specifier shall not be incomplete, or pointer or ref to incomplete other than pointer to cv void. */ is_ptr = TREE_CODE (core) == POINTER_TYPE; if (is_ptr || TREE_CODE (core) == REFERENCE_TYPE) core = TREE_TYPE (core); if (complain < 0) ok = 1; else if (TYPE_MAIN_VARIANT (core) == void_type_node) ok = is_ptr; else if (TREE_CODE (core) == TEMPLATE_TYPE_PARM) ok = 1; else ok = TYPE_SIZE (complete_type (core)) != NULL_TREE; if (ok) { tree probe; for (probe = list; probe; probe = TREE_CHAIN (probe)) if (same_type_p (TREE_VALUE (probe), spec)) break; if (!probe) { spec = build_decl_list (NULL_TREE, spec); TREE_CHAIN (spec) = list; list = spec; } } else if (complain) incomplete_type_error (NULL_TREE, core); return list; }