1 /* Some code common to C++ and ObjC++ front ends. 2 Copyright (C) 2004-2015 Free Software Foundation, Inc. 3 Contributed by Ziemowit Laski <zlaski@apple.com> 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify it under 8 the terms of the GNU General Public License as published by the Free 9 Software Foundation; either version 3, or (at your option) any later 10 version. 11 12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 13 WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15 for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING3. If not see 19 <http://www.gnu.org/licenses/>. */ 20 21 #include "config.h" 22 #include "system.h" 23 #include "coretypes.h" 24 #include "tm.h" 25 #include "hash-set.h" 26 #include "machmode.h" 27 #include "vec.h" 28 #include "double-int.h" 29 #include "input.h" 30 #include "alias.h" 31 #include "symtab.h" 32 #include "wide-int.h" 33 #include "inchash.h" 34 #include "tree.h" 35 #include "cp-tree.h" 36 #include "c-family/c-common.h" 37 #include "langhooks.h" 38 #include "langhooks-def.h" 39 #include "diagnostic.h" 40 #include "debug.h" 41 #include "cxx-pretty-print.h" 42 #include "cp-objcp-common.h" 43 44 /* Special routine to get the alias set for C++. */ 45 46 alias_set_type 47 cxx_get_alias_set (tree t) 48 { 49 if (IS_FAKE_BASE_TYPE (t)) 50 /* The base variant of a type must be in the same alias set as the 51 complete type. */ 52 return get_alias_set (TYPE_CONTEXT (t)); 53 54 /* Punt on PMFs until we canonicalize functions properly. */ 55 if (TYPE_PTRMEMFUNC_P (t) 56 || (POINTER_TYPE_P (t) 57 && TYPE_PTRMEMFUNC_P (TREE_TYPE (t)))) 58 return 0; 59 60 return c_common_get_alias_set (t); 61 } 62 63 /* Called from check_global_declarations. */ 64 65 bool 66 cxx_warn_unused_global_decl (const_tree decl) 67 { 68 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl)) 69 return false; 70 if (DECL_IN_SYSTEM_HEADER (decl)) 71 return false; 72 73 /* Const variables take the place of #defines in C++. */ 74 if (VAR_P (decl) && TREE_READONLY (decl)) 75 return false; 76 77 return true; 78 } 79 80 /* Langhook for tree_size: determine size of our 'x' and 'c' nodes. */ 81 size_t 82 cp_tree_size (enum tree_code code) 83 { 84 switch (code) 85 { 86 case PTRMEM_CST: return sizeof (struct ptrmem_cst); 87 case BASELINK: return sizeof (struct tree_baselink); 88 case TEMPLATE_PARM_INDEX: return sizeof (template_parm_index); 89 case DEFAULT_ARG: return sizeof (struct tree_default_arg); 90 case DEFERRED_NOEXCEPT: return sizeof (struct tree_deferred_noexcept); 91 case OVERLOAD: return sizeof (struct tree_overload); 92 case STATIC_ASSERT: return sizeof (struct tree_static_assert); 93 case TYPE_ARGUMENT_PACK: 94 case TYPE_PACK_EXPANSION: 95 return sizeof (struct tree_common); 96 97 case NONTYPE_ARGUMENT_PACK: 98 case EXPR_PACK_EXPANSION: 99 return sizeof (struct tree_exp); 100 101 case ARGUMENT_PACK_SELECT: 102 return sizeof (struct tree_argument_pack_select); 103 104 case TRAIT_EXPR: 105 return sizeof (struct tree_trait_expr); 106 107 case LAMBDA_EXPR: return sizeof (struct tree_lambda_expr); 108 109 case TEMPLATE_INFO: return sizeof (struct tree_template_info); 110 111 case USERDEF_LITERAL: return sizeof (struct tree_userdef_literal); 112 113 case TEMPLATE_DECL: return sizeof (struct tree_template_decl); 114 115 default: 116 if (TREE_CODE_CLASS (code) == tcc_declaration) 117 return sizeof (struct tree_decl_non_common); 118 gcc_unreachable (); 119 } 120 /* NOTREACHED */ 121 } 122 123 /* Returns true if T is a variably modified type, in the sense of C99. 124 FN is as passed to variably_modified_p. 125 This routine needs only check cases that cannot be handled by the 126 language-independent logic in tree.c. */ 127 128 bool 129 cp_var_mod_type_p (tree type, tree fn) 130 { 131 /* If TYPE is a pointer-to-member, it is variably modified if either 132 the class or the member are variably modified. */ 133 if (TYPE_PTRMEM_P (type)) 134 return (variably_modified_type_p (TYPE_PTRMEM_CLASS_TYPE (type), fn) 135 || variably_modified_type_p (TYPE_PTRMEM_POINTED_TO_TYPE (type), 136 fn)); 137 138 /* All other types are not variably modified. */ 139 return false; 140 } 141 142 /* This compares two types for equivalence ("compatible" in C-based languages). 143 This routine should only return 1 if it is sure. It should not be used 144 in contexts where erroneously returning 0 causes problems. */ 145 146 int 147 cxx_types_compatible_p (tree x, tree y) 148 { 149 return same_type_ignoring_top_level_qualifiers_p (x, y); 150 } 151 152 /* Return true if DECL is explicit member function. */ 153 154 bool 155 cp_function_decl_explicit_p (tree decl) 156 { 157 return (decl 158 && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl)) 159 && DECL_NONCONVERTING_P (decl)); 160 } 161 162 /* Return true if DECL is deleted special member function. */ 163 164 bool 165 cp_function_decl_deleted_p (tree decl) 166 { 167 return (decl 168 && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl)) 169 && DECL_DELETED_FN (decl)); 170 } 171 172 /* Stubs to keep c-opts.c happy. */ 173 void 174 push_file_scope (void) 175 { 176 } 177 178 void 179 pop_file_scope (void) 180 { 181 } 182 183 /* c-pragma.c needs to query whether a decl has extern "C" linkage. */ 184 bool 185 has_c_linkage (const_tree decl) 186 { 187 return DECL_EXTERN_C_P (decl); 188 } 189 190 static GTY ((cache)) 191 hash_table<tree_decl_map_cache_hasher> *shadowed_var_for_decl; 192 193 /* Lookup a shadowed var for FROM, and return it if we find one. */ 194 195 tree 196 decl_shadowed_for_var_lookup (tree from) 197 { 198 struct tree_decl_map *h, in; 199 in.base.from = from; 200 201 h = shadowed_var_for_decl->find_with_hash (&in, DECL_UID (from)); 202 if (h) 203 return h->to; 204 return NULL_TREE; 205 } 206 207 /* Insert a mapping FROM->TO in the shadowed var hashtable. */ 208 209 void 210 decl_shadowed_for_var_insert (tree from, tree to) 211 { 212 struct tree_decl_map *h; 213 214 h = ggc_alloc<tree_decl_map> (); 215 h->base.from = from; 216 h->to = to; 217 *shadowed_var_for_decl->find_slot_with_hash (h, DECL_UID (from), INSERT) = h; 218 } 219 220 void 221 init_shadowed_var_for_decl (void) 222 { 223 shadowed_var_for_decl 224 = hash_table<tree_decl_map_cache_hasher>::create_ggc (512); 225 } 226 227 /* Return true if stmt can fall through. Used by block_may_fallthru 228 default case. */ 229 230 bool 231 cxx_block_may_fallthru (const_tree stmt) 232 { 233 switch (TREE_CODE (stmt)) 234 { 235 case EXPR_STMT: 236 return block_may_fallthru (EXPR_STMT_EXPR (stmt)); 237 238 case THROW_EXPR: 239 return false; 240 241 default: 242 return true; 243 } 244 } 245 246 void 247 cp_common_init_ts (void) 248 { 249 MARK_TS_DECL_NON_COMMON (USING_DECL); 250 MARK_TS_DECL_COMMON (TEMPLATE_DECL); 251 252 MARK_TS_COMMON (TEMPLATE_TEMPLATE_PARM); 253 MARK_TS_COMMON (TEMPLATE_TYPE_PARM); 254 MARK_TS_COMMON (TEMPLATE_PARM_INDEX); 255 MARK_TS_COMMON (OVERLOAD); 256 MARK_TS_COMMON (TEMPLATE_INFO); 257 MARK_TS_COMMON (TYPENAME_TYPE); 258 MARK_TS_COMMON (TYPEOF_TYPE); 259 MARK_TS_COMMON (UNDERLYING_TYPE); 260 MARK_TS_COMMON (BASELINK); 261 MARK_TS_COMMON (TYPE_PACK_EXPANSION); 262 MARK_TS_COMMON (TYPE_ARGUMENT_PACK); 263 MARK_TS_COMMON (DECLTYPE_TYPE); 264 MARK_TS_COMMON (BOUND_TEMPLATE_TEMPLATE_PARM); 265 MARK_TS_COMMON (UNBOUND_CLASS_TEMPLATE); 266 267 MARK_TS_TYPED (EXPR_PACK_EXPANSION); 268 MARK_TS_TYPED (SWITCH_STMT); 269 MARK_TS_TYPED (IF_STMT); 270 MARK_TS_TYPED (FOR_STMT); 271 MARK_TS_TYPED (RANGE_FOR_STMT); 272 MARK_TS_TYPED (AGGR_INIT_EXPR); 273 MARK_TS_TYPED (EXPR_STMT); 274 MARK_TS_TYPED (EH_SPEC_BLOCK); 275 MARK_TS_TYPED (CLEANUP_STMT); 276 MARK_TS_TYPED (SCOPE_REF); 277 MARK_TS_TYPED (CAST_EXPR); 278 MARK_TS_TYPED (NON_DEPENDENT_EXPR); 279 MARK_TS_TYPED (MODOP_EXPR); 280 MARK_TS_TYPED (TRY_BLOCK); 281 MARK_TS_TYPED (THROW_EXPR); 282 MARK_TS_TYPED (HANDLER); 283 MARK_TS_TYPED (REINTERPRET_CAST_EXPR); 284 MARK_TS_TYPED (CONST_CAST_EXPR); 285 MARK_TS_TYPED (STATIC_CAST_EXPR); 286 MARK_TS_TYPED (DYNAMIC_CAST_EXPR); 287 MARK_TS_TYPED (IMPLICIT_CONV_EXPR); 288 MARK_TS_TYPED (TEMPLATE_ID_EXPR); 289 MARK_TS_TYPED (ARROW_EXPR); 290 MARK_TS_TYPED (SIZEOF_EXPR); 291 MARK_TS_TYPED (ALIGNOF_EXPR); 292 MARK_TS_TYPED (AT_ENCODE_EXPR); 293 MARK_TS_TYPED (UNARY_PLUS_EXPR); 294 MARK_TS_TYPED (TRAIT_EXPR); 295 MARK_TS_TYPED (TYPE_ARGUMENT_PACK); 296 MARK_TS_TYPED (NOEXCEPT_EXPR); 297 MARK_TS_TYPED (NONTYPE_ARGUMENT_PACK); 298 MARK_TS_TYPED (WHILE_STMT); 299 MARK_TS_TYPED (NEW_EXPR); 300 MARK_TS_TYPED (VEC_NEW_EXPR); 301 MARK_TS_TYPED (BREAK_STMT); 302 MARK_TS_TYPED (MEMBER_REF); 303 MARK_TS_TYPED (DOTSTAR_EXPR); 304 MARK_TS_TYPED (DO_STMT); 305 MARK_TS_TYPED (DELETE_EXPR); 306 MARK_TS_TYPED (VEC_DELETE_EXPR); 307 MARK_TS_TYPED (CONTINUE_STMT); 308 MARK_TS_TYPED (TAG_DEFN); 309 MARK_TS_TYPED (PSEUDO_DTOR_EXPR); 310 MARK_TS_TYPED (TYPEID_EXPR); 311 MARK_TS_TYPED (MUST_NOT_THROW_EXPR); 312 MARK_TS_TYPED (STMT_EXPR); 313 MARK_TS_TYPED (OFFSET_REF); 314 MARK_TS_TYPED (OFFSETOF_EXPR); 315 MARK_TS_TYPED (PTRMEM_CST); 316 MARK_TS_TYPED (EMPTY_CLASS_EXPR); 317 MARK_TS_TYPED (VEC_INIT_EXPR); 318 MARK_TS_TYPED (USING_STMT); 319 MARK_TS_TYPED (LAMBDA_EXPR); 320 MARK_TS_TYPED (CTOR_INITIALIZER); 321 MARK_TS_TYPED (ARRAY_NOTATION_REF); 322 } 323 324 #include "gt-cp-cp-objcp-common.h" 325