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author | peter <peter@FreeBSD.org> | 2008-06-01 00:03:21 +0000 |
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committer | peter <peter@FreeBSD.org> | 2008-06-01 00:03:21 +0000 |
commit | a2be5f0c15218b0177d73b17d9bcb7589965d685 (patch) | |
tree | c9f0cd9c22378356a1716d32e13e70bc90f98b9c /gcc/cp/typeck2.c | |
parent | 9e0f3cc19c9df1594c9cc36cfd8fddc83c52ad12 (diff) | |
download | FreeBSD-src-a2be5f0c15218b0177d73b17d9bcb7589965d685.zip FreeBSD-src-a2be5f0c15218b0177d73b17d9bcb7589965d685.tar.gz |
Reorganize the gcc vendor import work area. This flattens out a bunch
of unnecessary path components that are relics of cvs2svn.
(These are directory moves)
Diffstat (limited to 'gcc/cp/typeck2.c')
-rw-r--r-- | gcc/cp/typeck2.c | 1495 |
1 files changed, 1495 insertions, 0 deletions
diff --git a/gcc/cp/typeck2.c b/gcc/cp/typeck2.c new file mode 100644 index 0000000..baedbad --- /dev/null +++ b/gcc/cp/typeck2.c @@ -0,0 +1,1495 @@ +/* Report error messages, build initializers, and perform + some front-end optimizations for C++ compiler. + Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, + 1999, 2000, 2001, 2002, 2004, 2005, 2006 + Free Software Foundation, Inc. + Hacked by Michael Tiemann (tiemann@cygnus.com) + +This file is part of GCC. + +GCC 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. + +GCC 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 GCC; see the file COPYING. If not, write to +the Free Software Foundation, 51 Franklin Street, Fifth Floor, +Boston, MA 02110-1301, 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. */ + +#include "config.h" +#include "system.h" +#include "coretypes.h" +#include "tm.h" +#include "tree.h" +#include "cp-tree.h" +#include "flags.h" +#include "toplev.h" +#include "output.h" +#include "diagnostic.h" + +static tree +process_init_constructor (tree type, tree init); + + +/* Print an error message stemming from an attempt to use + BASETYPE as a base class for TYPE. */ + +tree +error_not_base_type (tree basetype, tree type) +{ + if (TREE_CODE (basetype) == FUNCTION_DECL) + basetype = DECL_CONTEXT (basetype); + error ("type %qT is not a base type for type %qT", basetype, type); + return error_mark_node; +} + +tree +binfo_or_else (tree base, tree type) +{ + tree binfo = lookup_base (type, base, ba_unique, NULL); + + if (binfo == error_mark_node) + return NULL_TREE; + else if (!binfo) + error_not_base_type (base, type); + return binfo; +} + +/* 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 (tree arg, const char* string, int soft) +{ + const char *fmt; + void (*fn) (const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2); + + if (soft) + fn = pedwarn; + else + fn = error; + + if (TREE_CODE (arg) == COMPONENT_REF) + { + if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0)))) + fmt = "%s of data-member %qD in read-only structure"; + else + fmt = "%s of read-only data-member %qD"; + (*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 %qD"; + else + fmt = "%s of read-only variable %qD"; + (*fn) (fmt, string, arg); + } + else if (TREE_CODE (arg) == PARM_DECL) + (*fn) ("%s of read-only parameter %qD", 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 %qD", string, TREE_OPERAND (arg, 0)); + else if (TREE_CODE (arg) == RESULT_DECL) + (*fn) ("%s of read-only named return value %qD", string, arg); + else if (TREE_CODE (arg) == FUNCTION_DECL) + (*fn) ("%s of function %qD", string, arg); + else + (*fn) ("%s of read-only location", string); +} + + +/* Structure that holds information about declarations whose type was + incomplete and we could not check whether it was abstract or not. */ + +struct pending_abstract_type GTY((chain_next ("%h.next"))) +{ + /* Declaration which we are checking for abstractness. It is either + a DECL node, or an IDENTIFIER_NODE if we do not have a full + declaration available. */ + tree decl; + + /* Type which will be checked for abstractness. */ + tree type; + + /* Position of the declaration. This is only needed for IDENTIFIER_NODEs, + because DECLs already carry locus information. */ + location_t locus; + + /* Link to the next element in list. */ + struct pending_abstract_type* next; +}; + + +/* Compute the hash value of the node VAL. This function is used by the + hash table abstract_pending_vars. */ + +static hashval_t +pat_calc_hash (const void* val) +{ + const struct pending_abstract_type *pat = + (const struct pending_abstract_type *) val; + return (hashval_t) TYPE_UID (pat->type); +} + + +/* Compare node VAL1 with the type VAL2. This function is used by the + hash table abstract_pending_vars. */ + +static int +pat_compare (const void* val1, const void* val2) +{ + const struct pending_abstract_type *pat1 = + (const struct pending_abstract_type *) val1; + tree type2 = (tree)val2; + + return (pat1->type == type2); +} + +/* Hash table that maintains pending_abstract_type nodes, for which we still + need to check for type abstractness. The key of the table is the type + of the declaration. */ +static GTY ((param_is (struct pending_abstract_type))) +htab_t abstract_pending_vars = NULL; + + +/* This function is called after TYPE is completed, and will check if there + are pending declarations for which we still need to verify the abstractness + of TYPE, and emit a diagnostic (through abstract_virtuals_error) if TYPE + turned out to be incomplete. */ + +void +complete_type_check_abstract (tree type) +{ + void **slot; + struct pending_abstract_type *pat; + location_t cur_loc = input_location; + + gcc_assert (COMPLETE_TYPE_P (type)); + + if (!abstract_pending_vars) + return; + + /* Retrieve the list of pending declarations for this type. */ + slot = htab_find_slot_with_hash (abstract_pending_vars, type, + (hashval_t)TYPE_UID (type), NO_INSERT); + if (!slot) + return; + pat = (struct pending_abstract_type*)*slot; + gcc_assert (pat); + + /* If the type is not abstract, do not do anything. */ + if (CLASSTYPE_PURE_VIRTUALS (type)) + { + struct pending_abstract_type *prev = 0, *next; + + /* Reverse the list to emit the errors in top-down order. */ + for (; pat; pat = next) + { + next = pat->next; + pat->next = prev; + prev = pat; + } + pat = prev; + + /* Go through the list, and call abstract_virtuals_error for each + element: it will issue a diagnostic if the type is abstract. */ + while (pat) + { + gcc_assert (type == pat->type); + + /* Tweak input_location so that the diagnostic appears at the correct + location. Notice that this is only needed if the decl is an + IDENTIFIER_NODE. */ + input_location = pat->locus; + abstract_virtuals_error (pat->decl, pat->type); + pat = pat->next; + } + } + + htab_clear_slot (abstract_pending_vars, slot); + + input_location = cur_loc; +} + + +/* 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 (tree decl, tree type) +{ + VEC(tree,gc) *pure; + + /* This function applies only to classes. Any other entity can never + be abstract. */ + if (!CLASS_TYPE_P (type)) + return 0; + + /* If the type is incomplete, we register it within a hash table, + so that we can check again once it is completed. This makes sense + only for objects for which we have a declaration or at least a + name. */ + if (!COMPLETE_TYPE_P (type)) + { + void **slot; + struct pending_abstract_type *pat; + + gcc_assert (!decl || DECL_P (decl) + || TREE_CODE (decl) == IDENTIFIER_NODE); + + if (!abstract_pending_vars) + abstract_pending_vars = htab_create_ggc (31, &pat_calc_hash, + &pat_compare, NULL); + + slot = htab_find_slot_with_hash (abstract_pending_vars, type, + (hashval_t)TYPE_UID (type), INSERT); + + pat = GGC_NEW (struct pending_abstract_type); + pat->type = type; + pat->decl = decl; + pat->locus = ((decl && DECL_P (decl)) + ? DECL_SOURCE_LOCATION (decl) + : input_location); + + pat->next = (struct pending_abstract_type *) *slot; + *slot = pat; + + return 0; + } + + if (!TYPE_SIZE (type)) + /* TYPE is being defined, and during that time + CLASSTYPE_PURE_VIRTUALS holds the inline friends. */ + return 0; + + pure = CLASSTYPE_PURE_VIRTUALS (type); + if (!pure) + return 0; + + if (decl) + { + if (TREE_CODE (decl) == RESULT_DECL) + return 0; + + if (TREE_CODE (decl) == VAR_DECL) + error ("cannot declare variable %q+D to be of abstract " + "type %qT", decl, type); + else if (TREE_CODE (decl) == PARM_DECL) + error ("cannot declare parameter %q+D to be of abstract type %qT", + decl, type); + else if (TREE_CODE (decl) == FIELD_DECL) + error ("cannot declare field %q+D to be of abstract type %qT", + decl, type); + else if (TREE_CODE (decl) == FUNCTION_DECL + && TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE) + error ("invalid abstract return type for member function %q+#D", decl); + else if (TREE_CODE (decl) == FUNCTION_DECL) + error ("invalid abstract return type for function %q+#D", decl); + else if (TREE_CODE (decl) == IDENTIFIER_NODE) + /* Here we do not have location information. */ + error ("invalid abstract type %qT for %qE", type, decl); + else + error ("invalid abstract type for %q+D", decl); + } + else + error ("cannot allocate an object of abstract type %qT", type); + + /* Only go through this once. */ + if (VEC_length (tree, pure)) + { + unsigned ix; + tree fn; + + inform ("%J because the following virtual functions are pure " + "within %qT:", TYPE_MAIN_DECL (type), type); + + for (ix = 0; VEC_iterate (tree, pure, ix, fn); ix++) + inform ("\t%+#D", fn); + /* Now truncate the vector. This leaves it non-null, so we know + there are pure virtuals, but empty so we don't list them out + again. */ + VEC_truncate (tree, pure, 0); + } + else + inform ("%J since type %qT has pure virtual functions", + TYPE_MAIN_DECL (type), 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. DIAG_TYPE indicates the + type of diagnostic: 0 for an error, 1 for a warning, 2 for a + pedwarn. */ + +void +cxx_incomplete_type_diagnostic (tree value, tree type, int diag_type) +{ + int decl = 0; + void (*p_msg) (const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2); + + if (diag_type == 1) + p_msg = warning0; + else if (diag_type == 2) + p_msg = pedwarn; + else + p_msg = error; + + /* Avoid duplicate error message. */ + if (TREE_CODE (type) == ERROR_MARK) + return; + + if (value != 0 && (TREE_CODE (value) == VAR_DECL + || TREE_CODE (value) == PARM_DECL + || TREE_CODE (value) == FIELD_DECL)) + { + p_msg ("%q+D has incomplete type", value); + decl = 1; + } + 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: + if (!decl) + p_msg ("invalid use of incomplete type %q#T", type); + if (!TYPE_TEMPLATE_INFO (type)) + p_msg ("forward declaration of %q+#T", type); + else + p_msg ("declaration of %q+#T", type); + break; + + case VOID_TYPE: + p_msg ("invalid use of %qT", type); + break; + + case ARRAY_TYPE: + if (TYPE_DOMAIN (type)) + { + type = TREE_TYPE (type); + goto retry; + } + p_msg ("invalid use of array with unspecified bounds"); + break; + + case OFFSET_TYPE: + bad_member: + p_msg ("invalid use of member (did you forget the %<&%> ?)"); + break; + + case TEMPLATE_TYPE_PARM: + p_msg ("invalid use of template type parameter %qT", type); + break; + + case BOUND_TEMPLATE_TEMPLATE_PARM: + p_msg ("invalid use of template template parameter %qT", + TYPE_NAME (type)); + break; + + case TYPENAME_TYPE: + p_msg ("invalid use of dependent type %qT", type); + break; + + case UNKNOWN_TYPE: + if (value && TREE_CODE (value) == COMPONENT_REF) + goto bad_member; + else if (value && TREE_CODE (value) == ADDR_EXPR) + p_msg ("address of overloaded function with no contextual " + "type information"); + else if (value && TREE_CODE (value) == OVERLOAD) + p_msg ("overloaded function with no contextual type information"); + else + p_msg ("insufficient contextual information to determine type"); + break; + + default: + gcc_unreachable (); + } +} + +/* Backward-compatibility interface to incomplete_type_diagnostic; + required by ../tree.c. */ +#undef cxx_incomplete_type_error +void +cxx_incomplete_type_error (tree value, tree type) +{ + cxx_incomplete_type_diagnostic (value, type, 0); +} + + +/* The recursive part of split_nonconstant_init. DEST is an lvalue + expression to which INIT should be assigned. INIT is a CONSTRUCTOR. */ + +static void +split_nonconstant_init_1 (tree dest, tree init) +{ + unsigned HOST_WIDE_INT idx; + tree field_index, value; + tree type = TREE_TYPE (dest); + tree inner_type = NULL; + bool array_type_p = false; + + switch (TREE_CODE (type)) + { + case ARRAY_TYPE: + inner_type = TREE_TYPE (type); + array_type_p = true; + /* FALLTHRU */ + + case RECORD_TYPE: + case UNION_TYPE: + case QUAL_UNION_TYPE: + FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init), idx, + field_index, value) + { + /* The current implementation of this algorithm assumes that + the field was set for all the elements. This is usually done + by process_init_constructor. */ + gcc_assert (field_index); + + if (!array_type_p) + inner_type = TREE_TYPE (field_index); + + if (TREE_CODE (value) == CONSTRUCTOR) + { + tree sub; + + if (array_type_p) + sub = build4 (ARRAY_REF, inner_type, dest, field_index, + NULL_TREE, NULL_TREE); + else + sub = build3 (COMPONENT_REF, inner_type, dest, field_index, + NULL_TREE); + + split_nonconstant_init_1 (sub, value); + } + else if (!initializer_constant_valid_p (value, inner_type)) + { + tree code; + tree sub; + + /* FIXME: Ordered removal is O(1) so the whole function is + worst-case quadratic. This could be fixed using an aside + bitmap to record which elements must be removed and remove + them all at the same time. Or by merging + split_non_constant_init into process_init_constructor_array, + that is separating constants from non-constants while building + the vector. */ + VEC_ordered_remove (constructor_elt, CONSTRUCTOR_ELTS (init), + idx); + --idx; + + if (array_type_p) + sub = build4 (ARRAY_REF, inner_type, dest, field_index, + NULL_TREE, NULL_TREE); + else + sub = build3 (COMPONENT_REF, inner_type, dest, field_index, + NULL_TREE); + + code = build2 (INIT_EXPR, inner_type, sub, value); + code = build_stmt (EXPR_STMT, code); + add_stmt (code); + continue; + } + } + break; + + case VECTOR_TYPE: + if (!initializer_constant_valid_p (init, type)) + { + tree code; + tree cons = copy_node (init); + CONSTRUCTOR_ELTS (init) = NULL; + code = build2 (MODIFY_EXPR, type, dest, cons); + code = build_stmt (EXPR_STMT, code); + add_stmt (code); + } + break; + + default: + gcc_unreachable (); + } + + /* The rest of the initializer is now a constant. */ + TREE_CONSTANT (init) = 1; +} + +/* A subroutine of store_init_value. Splits non-constant static + initializer INIT into a constant part and generates code to + perform the non-constant part of the initialization to DEST. + Returns the code for the runtime init. */ + +static tree +split_nonconstant_init (tree dest, tree init) +{ + tree code; + + if (TREE_CODE (init) == CONSTRUCTOR) + { + code = push_stmt_list (); + split_nonconstant_init_1 (dest, init); + code = pop_stmt_list (code); + DECL_INITIAL (dest) = init; + TREE_READONLY (dest) = 0; + } + else + code = build2 (INIT_EXPR, TREE_TYPE (dest), dest, init); + + return code; +} + +/* 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 code to be executed if initialization could not be performed + for static variable. In that case, caller must emit the code. */ + +tree +store_init_value (tree decl, tree init) +{ + 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 (IS_AGGR_TYPE (type)) + { + gcc_assert (TYPE_HAS_TRIVIAL_INIT_REF (type) + || TREE_CODE (init) == CONSTRUCTOR); + + if (TREE_CODE (init) == TREE_LIST) + { + error ("constructor syntax used, but no constructor declared " + "for type %qT", type); + init = build_constructor_from_list (NULL_TREE, nreverse (init)); + } + } + else if (TREE_CODE (init) == TREE_LIST + && TREE_TYPE (init) != unknown_type_node) + { + if (TREE_CODE (decl) == RESULT_DECL) + init = build_x_compound_expr_from_list (init, + "return value initializer"); + 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);' */ + init = build_x_compound_expr_from_list (init, "initializer"); + } + + /* End of special C++ code. */ + + /* Digest the specified initializer into an expression. */ + value = digest_init (type, init); + /* If the initializer is not a constant, fill in DECL_INITIAL with + the bits that are constant, and then return an expression that + will perform the dynamic initialization. */ + if (value != error_mark_node + && (TREE_SIDE_EFFECTS (value) + || ! initializer_constant_valid_p (value, TREE_TYPE (value)))) + return split_nonconstant_init (decl, value); + /* If the value is a constant, just put it in DECL_INITIAL. If DECL + is an automatic variable, the middle end will turn this into a + dynamic initialization later. */ + DECL_INITIAL (decl) = value; + return NULL_TREE; +} + + +/* Process the initializer INIT for a variable of type TYPE, emitting + diagnostics for invalid initializers and converting the initializer as + appropriate. + + For aggregate types, it assumes that reshape_init has already run, thus the + initializer will have the right shape (brace elision has been undone). */ + +tree +digest_init (tree type, tree init) +{ + enum tree_code code = TREE_CODE (type); + + if (init == error_mark_node) + return error_mark_node; + + gcc_assert (init); + + /* We must strip the outermost array type when completing the type, + because the its bounds might be incomplete at the moment. */ + if (!complete_type_or_else (TREE_CODE (type) == ARRAY_TYPE + ? TREE_TYPE (type) : type, NULL_TREE)) + return error_mark_node; + + /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue + (g++.old-deja/g++.law/casts2.C). */ + if (TREE_CODE (init) == NON_LVALUE_EXPR) + init = TREE_OPERAND (init, 0); + + /* Initialization of an array of chars from a string constant. The initializer + can be optionally enclosed in braces, but reshape_init has already removed + them if they were present. */ + if (code == ARRAY_TYPE) + { + tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type)); + if (char_type_p (typ1) + /*&& init */ + && TREE_CODE (init) == STRING_CST) + { + tree char_type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (init))); + + if (char_type != char_type_node + && TYPE_PRECISION (typ1) == BITS_PER_UNIT) + { + error ("char-array initialized from wide string"); + return error_mark_node; + } + if (char_type == char_type_node + && TYPE_PRECISION (typ1) != BITS_PER_UNIT) + { + error ("int-array initialized from non-wide string"); + return error_mark_node; + } + + TREE_TYPE (init) = type; + if (TYPE_DOMAIN (type) != 0 && TREE_CONSTANT (TYPE_SIZE (type))) + { + 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 (init)) + pedwarn ("initializer-string for array of chars is too long"); + } + return init; + } + } + + /* Handle scalar types (including conversions) and references. */ + if (TREE_CODE (type) != COMPLEX_TYPE + && (SCALAR_TYPE_P (type) || code == REFERENCE_TYPE)) + return convert_for_initialization (0, type, init, LOOKUP_NORMAL, + "initialization", NULL_TREE, 0); + + /* Come here only for aggregates: records, arrays, unions, complex numbers + and vectors. */ + gcc_assert (TREE_CODE (type) == ARRAY_TYPE + || TREE_CODE (type) == VECTOR_TYPE + || TREE_CODE (type) == RECORD_TYPE + || TREE_CODE (type) == UNION_TYPE + || TREE_CODE (type) == COMPLEX_TYPE); + + if (BRACE_ENCLOSED_INITIALIZER_P (init)) + return process_init_constructor (type, init); + else + { + if (COMPOUND_LITERAL_P (init) && TREE_CODE (type) == ARRAY_TYPE) + { + error ("cannot initialize aggregate of type %qT with " + "a compound literal", type); + + return error_mark_node; + } + + if (TREE_CODE (type) == ARRAY_TYPE + && TREE_CODE (init) != CONSTRUCTOR) + { + error ("array must be initialized with a brace-enclosed" + " initializer"); + return error_mark_node; + } + + return convert_for_initialization (NULL_TREE, type, init, + LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING, + "initialization", NULL_TREE, 0); + } +} + + +/* Set of flags used within process_init_constructor to describe the + initializers. */ +#define PICFLAG_ERRONEOUS 1 +#define PICFLAG_NOT_ALL_CONSTANT 2 +#define PICFLAG_NOT_ALL_SIMPLE 4 + +/* Given an initializer INIT, return the flag (PICFLAG_*) which better + describe it. */ + +static int +picflag_from_initializer (tree init) +{ + if (init == error_mark_node) + return PICFLAG_ERRONEOUS; + else if (!TREE_CONSTANT (init)) + return PICFLAG_NOT_ALL_CONSTANT; + else if (!initializer_constant_valid_p (init, TREE_TYPE (init))) + return PICFLAG_NOT_ALL_SIMPLE; + return 0; +} + +/* Subroutine of process_init_constructor, which will process an initializer + INIT for a array or vector of type TYPE. Returns the flags (PICFLAG_*) which + describe the initializers. */ + +static int +process_init_constructor_array (tree type, tree init) +{ + unsigned HOST_WIDE_INT i, len = 0; + int flags = 0; + bool unbounded = false; + constructor_elt *ce; + VEC(constructor_elt,gc) *v = CONSTRUCTOR_ELTS (init); + + gcc_assert (TREE_CODE (type) == ARRAY_TYPE + || TREE_CODE (type) == VECTOR_TYPE); + + if (TREE_CODE (type) == ARRAY_TYPE) + { + tree domain = TYPE_DOMAIN (type); + if (domain) + len = (TREE_INT_CST_LOW (TYPE_MAX_VALUE (domain)) + - TREE_INT_CST_LOW (TYPE_MIN_VALUE (domain)) + + 1); + else + unbounded = true; /* Take as many as there are. */ + } + else + /* Vectors are like simple fixed-size arrays. */ + len = TYPE_VECTOR_SUBPARTS (type); + + /* There cannot be more initializers than needed as otherwise + reshape_init would have already rejected the initializer. */ + if (!unbounded) + gcc_assert (VEC_length (constructor_elt, v) <= len); + + for (i = 0; VEC_iterate (constructor_elt, v, i, ce); ++i) + { + if (ce->index) + { + gcc_assert (TREE_CODE (ce->index) == INTEGER_CST); + if (compare_tree_int (ce->index, i) != 0) + { + ce->value = error_mark_node; + sorry ("non-trivial designated initializers not supported"); + } + } + else + ce->index = size_int (i); + gcc_assert (ce->value); + ce->value = digest_init (TREE_TYPE (type), ce->value); + + if (ce->value != error_mark_node) + gcc_assert (same_type_ignoring_top_level_qualifiers_p + (TREE_TYPE (type), TREE_TYPE (ce->value))); + + flags |= picflag_from_initializer (ce->value); + } + + /* No more initializers. If the array is unbounded, we are done. Otherwise, + we must add initializers ourselves. */ + if (!unbounded) + for (; i < len; ++i) + { + tree next; + + 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))) + next = build_functional_cast (TREE_TYPE (type), NULL_TREE); + else + next = build_constructor (NULL_TREE, NULL); + next = digest_init (TREE_TYPE (type), next); + } + else if (!zero_init_p (TREE_TYPE (type))) + next = build_zero_init (TREE_TYPE (type), + /*nelts=*/NULL_TREE, + /*static_storage_p=*/false); + else + /* The default zero-initialization is fine for us; don't + add anything to the CONSTRUCTOR. */ + break; + + flags |= picflag_from_initializer (next); + CONSTRUCTOR_APPEND_ELT (v, size_int (i), next); + } + + CONSTRUCTOR_ELTS (init) = v; + return flags; +} + +/* Subroutine of process_init_constructor, which will process an initializer + INIT for a class of type TYPE. Returns the flags (PICFLAG_*) which describe + the initializers. */ + +static int +process_init_constructor_record (tree type, tree init) +{ + VEC(constructor_elt,gc) *v = NULL; + int flags = 0; + tree field; + unsigned HOST_WIDE_INT idx = 0; + + gcc_assert (TREE_CODE (type) == RECORD_TYPE); + gcc_assert (!CLASSTYPE_VBASECLASSES (type)); + gcc_assert (!TYPE_BINFO (type) + || !BINFO_N_BASE_BINFOS (TYPE_BINFO (type))); + gcc_assert (!TYPE_POLYMORPHIC_P (type)); + + /* Generally, we will always have an index for each initializer (which is + a FIELD_DECL, put by reshape_init), but compound literals don't go trough + reshape_init. So we need to handle both cases. */ + for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) + { + tree next; + + if (!DECL_NAME (field) && DECL_C_BIT_FIELD (field)) + { + flags |= picflag_from_initializer (integer_zero_node); + CONSTRUCTOR_APPEND_ELT (v, field, integer_zero_node); + continue; + } + + if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field)) + continue; + + if (idx < VEC_length (constructor_elt, CONSTRUCTOR_ELTS (init))) + { + constructor_elt *ce = VEC_index (constructor_elt, + CONSTRUCTOR_ELTS (init), idx); + if (ce->index) + { + /* We can have either a FIELD_DECL or an IDENTIFIER_NODE. The + latter case can happen in templates where lookup has to be + deferred. */ + gcc_assert (TREE_CODE (ce->index) == FIELD_DECL + || TREE_CODE (ce->index) == IDENTIFIER_NODE); + if (ce->index != field + && ce->index != DECL_NAME (field)) + { + ce->value = error_mark_node; + sorry ("non-trivial designated initializers not supported"); + } + } + + gcc_assert (ce->value); + next = digest_init (TREE_TYPE (field), ce->value); + ++idx; + } + 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))) + next = build_functional_cast (TREE_TYPE (field), NULL_TREE); + else + next = build_constructor (NULL_TREE, NULL); + + next = digest_init (TREE_TYPE (field), next); + + /* Warn when some struct elements are implicitly initialized. */ + warning (OPT_Wmissing_field_initializers, + "missing initializer for member %qD", field); + } + else + { + if (TREE_READONLY (field)) + error ("uninitialized const member %qD", field); + else if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (TREE_TYPE (field))) + error ("member %qD with uninitialized const fields", field); + else if (TREE_CODE (TREE_TYPE (field)) == REFERENCE_TYPE) + error ("member %qD is uninitialized reference", field); + + /* Warn when some struct elements are implicitly initialized + to zero. */ + warning (OPT_Wmissing_field_initializers, + "missing initializer for member %qD", field); + + if (!zero_init_p (TREE_TYPE (field))) + next = build_zero_init (TREE_TYPE (field), /*nelts=*/NULL_TREE, + /*static_storage_p=*/false); + else + /* The default zero-initialization is fine for us; don't + add anything to the CONSTRUCTOR. */ + continue; + } + + flags |= picflag_from_initializer (next); + CONSTRUCTOR_APPEND_ELT (v, field, next); + } + + CONSTRUCTOR_ELTS (init) = v; + return flags; +} + +/* Subroutine of process_init_constructor, which will process a single + initializer INIT for a union of type TYPE. Returns the flags (PICFLAG_*) + which describe the initializer. */ + +static int +process_init_constructor_union (tree type, tree init) +{ + constructor_elt *ce; + + /* If the initializer was empty, use default zero initialization. */ + if (VEC_empty (constructor_elt, CONSTRUCTOR_ELTS (init))) + return 0; + + gcc_assert (VEC_length (constructor_elt, CONSTRUCTOR_ELTS (init)) == 1); + ce = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (init), 0); + + /* If this element specifies a field, initialize via that field. */ + if (ce->index) + { + if (TREE_CODE (ce->index) == FIELD_DECL) + ; + else if (TREE_CODE (ce->index) == IDENTIFIER_NODE) + { + /* This can happen within a cast, see g++.dg/opt/cse2.C. */ + tree name = ce->index; + tree field; + for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) + if (DECL_NAME (field) == name) + break; + if (!field) + { + error ("no field %qD found in union being initialized", field); + ce->value = error_mark_node; + } + ce->index = field; + } + else + { + gcc_assert (TREE_CODE (ce->index) == INTEGER_CST + || TREE_CODE (ce->index) == RANGE_EXPR); + error ("index value instead of field name in union initializer"); + ce->value = error_mark_node; + } + } + else + { + /* Find the first named field. ANSI decided in September 1990 + that only named fields count here. */ + tree field = TYPE_FIELDS (type); + while (field && (!DECL_NAME (field) || TREE_CODE (field) != FIELD_DECL)) + field = TREE_CHAIN (field); + gcc_assert (field); + ce->index = field; + } + + if (ce->value && ce->value != error_mark_node) + ce->value = digest_init (TREE_TYPE (ce->index), ce->value); + + return picflag_from_initializer (ce->value); +} + +/* Process INIT, a constructor for a variable of aggregate type TYPE. The + constructor is a brace-enclosed initializer, and will be modified in-place. + + Each element is converted to the right type through digest_init, and + missing initializers are added following the language rules (zero-padding, + etc.). + + After the execution, the initializer will have TREE_CONSTANT if all elts are + constant, and TREE_STATIC set if, in addition, all elts are simple enough + constants that the assembler and linker can compute them. + + The function returns the initializer itself, or error_mark_node in case + of error. */ + +static tree +process_init_constructor (tree type, tree init) +{ + int flags; + + gcc_assert (BRACE_ENCLOSED_INITIALIZER_P (init)); + + if (TREE_CODE (type) == ARRAY_TYPE || TREE_CODE (type) == VECTOR_TYPE) + flags = process_init_constructor_array (type, init); + else if (TREE_CODE (type) == RECORD_TYPE) + flags = process_init_constructor_record (type, init); + else if (TREE_CODE (type) == UNION_TYPE) + flags = process_init_constructor_union (type, init); + else + gcc_unreachable (); + + if (flags & PICFLAG_ERRONEOUS) + return error_mark_node; + + TREE_TYPE (init) = type; + if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type) == NULL_TREE) + cp_complete_array_type (&TREE_TYPE (init), init, /*do_default=*/0); + if (!(flags & PICFLAG_NOT_ALL_CONSTANT)) + { + TREE_CONSTANT (init) = 1; + TREE_INVARIANT (init) = 1; + if (!(flags & PICFLAG_NOT_ALL_SIMPLE)) + TREE_STATIC (init) = 1; + } + return init; +} + +/* Given a structure or union value DATUM, construct and return + the structure or union component which results from narrowing + that value to the base 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. + + I used to think that this was nonconformant, that the standard specified + that first we look up ii in A, then convert x to an L& and pull out the + ii part. But in fact, it does say that we convert x to an A&; A here + is known as the "naming class". (jason 2000-12-19) + + BINFO_P points to a variable initialized either to NULL_TREE or to the + binfo for the specific base subobject we want to convert to. */ + +tree +build_scoped_ref (tree datum, tree basetype, tree* binfo_p) +{ + tree binfo; + + if (datum == error_mark_node) + return error_mark_node; + if (*binfo_p) + binfo = *binfo_p; + else + binfo = lookup_base (TREE_TYPE (datum), basetype, ba_check, NULL); + + if (!binfo || binfo == error_mark_node) + { + *binfo_p = NULL_TREE; + if (!binfo) + error_not_base_type (basetype, TREE_TYPE (datum)); + return error_mark_node; + } + + *binfo_p = binfo; + return build_base_path (PLUS_EXPR, datum, binfo, 1); +} + +/* 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 (tree expr) +{ + tree orig_expr = expr; + tree types_memoized = NULL_TREE; + tree type = TREE_TYPE (expr); + tree last_rval = NULL_TREE; + + if (type == error_mark_node) + return error_mark_node; + + if (processing_template_decl) + { + if (type_dependent_expression_p (expr)) + return build_min_nt (ARROW_EXPR, expr); + expr = build_non_dependent_expr (expr); + } + + if (IS_AGGR_TYPE (type)) + { + while ((expr = build_new_op (COMPONENT_REF, LOOKUP_NORMAL, expr, + NULL_TREE, NULL_TREE, + /*overloaded_p=*/NULL))) + { + if (expr == error_mark_node) + return error_mark_node; + + if (value_member (TREE_TYPE (expr), types_memoized)) + { + error ("circular pointer delegation detected"); + return error_mark_node; + } + else + { + types_memoized = tree_cons (NULL_TREE, TREE_TYPE (expr), + types_memoized); + } + last_rval = expr; + } + + if (last_rval == NULL_TREE) + { + error ("base operand of %<->%> has non-pointer type %qT", type); + return error_mark_node; + } + + if (TREE_CODE (TREE_TYPE (last_rval)) == REFERENCE_TYPE) + last_rval = convert_from_reference (last_rval); + } + else + last_rval = decay_conversion (expr); + + if (TREE_CODE (TREE_TYPE (last_rval)) == POINTER_TYPE) + { + if (processing_template_decl) + { + expr = build_min_non_dep (ARROW_EXPR, last_rval, orig_expr); + /* It will be dereferenced. */ + TREE_TYPE (expr) = TREE_TYPE (TREE_TYPE (last_rval)); + return expr; + } + + return build_indirect_ref (last_rval, NULL); + } + + if (types_memoized) + error ("result of %<operator->()%> yields non-pointer result"); + else + error ("base operand of %<->%> is not a pointer"); + return error_mark_node; +} + +/* Return an expression for "DATUM .* COMPONENT". DATUM has not + already been checked out to be of aggregate type. */ + +tree +build_m_component_ref (tree datum, tree component) +{ + tree ptrmem_type; + tree objtype; + tree type; + tree binfo; + tree ctype; + + if (error_operand_p (datum) || error_operand_p (component)) + return error_mark_node; + + ptrmem_type = TREE_TYPE (component); + if (!TYPE_PTR_TO_MEMBER_P (ptrmem_type)) + { + error ("%qE cannot be used as a member pointer, since it is of " + "type %qT", + component, ptrmem_type); + return error_mark_node; + } + + objtype = TYPE_MAIN_VARIANT (TREE_TYPE (datum)); + if (! IS_AGGR_TYPE (objtype)) + { + error ("cannot apply member pointer %qE to %qE, which is of " + "non-class type %qT", + component, datum, objtype); + return error_mark_node; + } + + type = TYPE_PTRMEM_POINTED_TO_TYPE (ptrmem_type); + ctype = complete_type (TYPE_PTRMEM_CLASS_TYPE (ptrmem_type)); + + if (!COMPLETE_TYPE_P (ctype)) + { + if (!same_type_p (ctype, objtype)) + goto mismatch; + binfo = NULL; + } + else + { + binfo = lookup_base (objtype, ctype, ba_check, NULL); + + if (!binfo) + { + mismatch: + error ("pointer to member type %qT incompatible with object " + "type %qT", + type, objtype); + return error_mark_node; + } + else if (binfo == error_mark_node) + return error_mark_node; + } + + if (TYPE_PTRMEM_P (ptrmem_type)) + { + /* Compute the type of the field, as described in [expr.ref]. + There's no such thing as a mutable pointer-to-member, so + things are not as complex as they are for references to + non-static data members. */ + type = cp_build_qualified_type (type, + (cp_type_quals (type) + | cp_type_quals (TREE_TYPE (datum)))); + + datum = build_address (datum); + + /* Convert object to the correct base. */ + if (binfo) + datum = build_base_path (PLUS_EXPR, datum, binfo, 1); + + /* Build an expression for "object + offset" where offset is the + value stored in the pointer-to-data-member. */ + datum = build2 (PLUS_EXPR, build_pointer_type (type), + datum, build_nop (ptrdiff_type_node, component)); + return build_indirect_ref (datum, 0); + } + else + return build2 (OFFSET_REF, type, datum, component); +} + +/* Return a tree node for the expression TYPENAME '(' PARMS ')'. */ + +tree +build_functional_cast (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) == TYPE_DECL) + type = TREE_TYPE (exp); + else + type = exp; + + if (processing_template_decl) + { + tree t = build_min (CAST_EXPR, type, parms); + /* We don't know if it will or will not have side effects. */ + TREE_SIDE_EFFECTS (t) = 1; + return t; + } + + if (! IS_AGGR_TYPE (type)) + { + if (parms == NULL_TREE) + return cp_convert (type, integer_zero_node); + + /* This must build a C cast. */ + parms = build_x_compound_expr_from_list (parms, "functional cast"); + 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 (!complete_type_or_else (type, NULL_TREE)) + 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. */ + if (parms == NULL_TREE + && !CLASSTYPE_NON_POD_P (type) + && TYPE_HAS_DEFAULT_CONSTRUCTOR (type)) + { + exp = build_zero_init (type, + /*nelts=*/NULL_TREE, + /*static_storage_p=*/false); + return get_target_expr (exp); + } + + exp = build_special_member_call (NULL_TREE, complete_ctor_identifier, parms, + type, LOOKUP_NORMAL); + + if (exp == error_mark_node) + return error_mark_node; + + return build_cplus_new (type, exp); +} + + +/* 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 (tree list, tree spec, int complain) +{ + bool ok; + tree core = spec; + bool is_ptr; + int diag_type = -1; /* none */ + + if (spec == error_mark_node) + return list; + + gcc_assert (spec && (!list || TREE_VALUE (list))); + + /* [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 = true; + else if (VOID_TYPE_P (core)) + ok = is_ptr; + else if (TREE_CODE (core) == TEMPLATE_TYPE_PARM) + ok = true; + else if (processing_template_decl) + ok = true; + else + { + ok = true; + /* 15.4/1 says that types in an exception specifier must be complete, + but it seems more reasonable to only require this on definitions + and calls. So just give a pedwarn at this point; we will give an + error later if we hit one of those two cases. */ + if (!COMPLETE_TYPE_P (complete_type (core))) + diag_type = 2; /* pedwarn */ + } + + if (ok) + { + tree probe; + + for (probe = list; probe; probe = TREE_CHAIN (probe)) + if (same_type_p (TREE_VALUE (probe), spec)) + break; + if (!probe) + list = tree_cons (NULL_TREE, spec, list); + } + else + diag_type = 0; /* error */ + + if (diag_type >= 0 && complain) + cxx_incomplete_type_diagnostic (NULL_TREE, core, diag_type); + + return list; +} + +/* Combine the two exceptions specifier lists LIST and ADD, and return + their union. */ + +tree +merge_exception_specifiers (tree list, tree add) +{ + if (!list || !add) + return NULL_TREE; + else if (!TREE_VALUE (list)) + return add; + else if (!TREE_VALUE (add)) + return list; + else + { + tree orig_list = list; + + for (; add; add = TREE_CHAIN (add)) + { + tree spec = TREE_VALUE (add); + tree probe; + + for (probe = orig_list; probe; probe = TREE_CHAIN (probe)) + if (same_type_p (TREE_VALUE (probe), spec)) + break; + if (!probe) + { + spec = build_tree_list (NULL_TREE, spec); + TREE_CHAIN (spec) = list; + list = spec; + } + } + } + return list; +} + +/* Subroutine of build_call. Ensure that each of the types in the + exception specification is complete. Technically, 15.4/1 says that + they need to be complete when we see a declaration of the function, + but we should be able to get away with only requiring this when the + function is defined or called. See also add_exception_specifier. */ + +void +require_complete_eh_spec_types (tree fntype, tree decl) +{ + tree raises; + /* Don't complain about calls to op new. */ + if (decl && DECL_ARTIFICIAL (decl)) + return; + for (raises = TYPE_RAISES_EXCEPTIONS (fntype); raises; + raises = TREE_CHAIN (raises)) + { + tree type = TREE_VALUE (raises); + if (type && !COMPLETE_TYPE_P (type)) + { + if (decl) + error + ("call to function %qD which throws incomplete type %q#T", + decl, type); + else + error ("call to function which throws incomplete type %q#T", + decl); + } + } +} + + +#include "gt-cp-typeck2.h" |