gcc/cp/cp-objcp-common.c

   1 /* Some code common to C++ and ObjC++ front ends.
   2    Copyright (C) 2004-2013 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 "tree.h"
  26 #include "cp-tree.h"
  27 #include "c-family/c-common.h"
  28 #include "langhooks.h"
  29 #include "langhooks-def.h"
  30 #include "diagnostic.h"
  31 #include "debug.h"
  32 #include "cxx-pretty-print.h"
  33 #include "cp-objcp-common.h"
  34
  35 /* Special routine to get the alias set for C++.  */
  36
  37 alias_set_type
  38 cxx_get_alias_set (tree t)
  39 {
  40   if (IS_FAKE_BASE_TYPE (t))
  41     /* The base variant of a type must be in the same alias set as the
  42        complete type.  */
  43     return get_alias_set (TYPE_CONTEXT (t));
  44
  45   /* Punt on PMFs until we canonicalize functions properly.  */
  46   if (TYPE_PTRMEMFUNC_P (t)
  47       || (POINTER_TYPE_P (t)
  48           && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))))
  49     return 0;
  50
  51   return c_common_get_alias_set (t);
  52 }
  53
  54 /* Called from check_global_declarations.  */
  55
  56 bool
  57 cxx_warn_unused_global_decl (const_tree decl)
  58 {
  59   if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl))
  60     return false;
  61   if (DECL_IN_SYSTEM_HEADER (decl))
  62     return false;
  63
  64   /* Const variables take the place of #defines in C++.  */
  65   if (TREE_CODE (decl) == VAR_DECL && TREE_READONLY (decl))
  66     return false;
  67
  68   return true;
  69 }
  70
  71 /* Langhook for tree_size: determine size of our 'x' and 'c' nodes.  */
  72 size_t
  73 cp_tree_size (enum tree_code code)
  74 {
  75   switch (code)
  76     {
  77     case PTRMEM_CST:            return sizeof (struct ptrmem_cst);
  78     case BASELINK:              return sizeof (struct tree_baselink);
  79     case TEMPLATE_PARM_INDEX:   return sizeof (template_parm_index);
  80     case DEFAULT_ARG:           return sizeof (struct tree_default_arg);
  81     case DEFERRED_NOEXCEPT:     return sizeof (struct tree_deferred_noexcept);
  82     case OVERLOAD:              return sizeof (struct tree_overload);
  83     case STATIC_ASSERT:         return sizeof (struct tree_static_assert);
  84     case TYPE_ARGUMENT_PACK:
  85     case TYPE_PACK_EXPANSION:
  86       return sizeof (struct tree_common);
  87
  88     case NONTYPE_ARGUMENT_PACK:
  89     case EXPR_PACK_EXPANSION:
  90       return sizeof (struct tree_exp);
  91
  92     case ARGUMENT_PACK_SELECT:
  93       return sizeof (struct tree_argument_pack_select);
  94
  95     case TRAIT_EXPR:
  96       return sizeof (struct tree_trait_expr);
  97
  98     case LAMBDA_EXPR:           return sizeof (struct tree_lambda_expr);
  99
 100     case TEMPLATE_INFO:         return sizeof (struct tree_template_info);
 101
 102     case USERDEF_LITERAL:       return sizeof (struct tree_userdef_literal);
 103
 104     default:
 105       gcc_unreachable ();
 106     }
 107   /* NOTREACHED */
 108 }
 109
 110 /* Returns true if T is a variably modified type, in the sense of C99.
 111    FN is as passed to variably_modified_p.
 112    This routine needs only check cases that cannot be handled by the
 113    language-independent logic in tree.c.  */
 114
 115 bool
 116 cp_var_mod_type_p (tree type, tree fn)
 117 {
 118   /* If TYPE is a pointer-to-member, it is variably modified if either
 119      the class or the member are variably modified.  */
 120   if (TYPE_PTRMEM_P (type))
 121     return (variably_modified_type_p (TYPE_PTRMEM_CLASS_TYPE (type), fn)
 122             || variably_modified_type_p (TYPE_PTRMEM_POINTED_TO_TYPE (type),
 123                                          fn));
 124
 125   /* All other types are not variably modified.  */
 126   return false;
 127 }
 128
 129 /* Construct a C++-aware pretty-printer for CONTEXT.  It is assumed
 130    that CONTEXT->printer is an already constructed basic pretty_printer.  */
 131 void
 132 cxx_initialize_diagnostics (diagnostic_context *context)
 133 {
 134   pretty_printer *base;
 135   cxx_pretty_printer *pp;
 136
 137   c_common_initialize_diagnostics (context);
 138
 139   base = context->printer;
 140   pp = XNEW (cxx_pretty_printer);
 141   memcpy (pp_base (pp), base, sizeof (pretty_printer));
 142   pp_cxx_pretty_printer_init (pp);
 143   context->printer = (pretty_printer *) pp;
 144
 145   /* It is safe to free this object because it was previously malloc()'d.  */
 146   free (base);
 147 }
 148
 149 /* This compares two types for equivalence ("compatible" in C-based languages).
 150    This routine should only return 1 if it is sure.  It should not be used
 151    in contexts where erroneously returning 0 causes problems.  */
 152
 153 int
 154 cxx_types_compatible_p (tree x, tree y)
 155 {
 156   return same_type_ignoring_top_level_qualifiers_p (x, y);
 157 }
 158
 159 /* Return true if DECL is explicit member function.  */
 160
 161 bool
 162 cp_function_decl_explicit_p (tree decl)
 163 {
 164   return (decl
 165           && FUNCTION_FIRST_USER_PARMTYPE (decl) != void_list_node
 166           && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl))
 167           && DECL_NONCONVERTING_P (decl));
 168 }
 169
 170 /* Stubs to keep c-opts.c happy.  */
 171 void
 172 push_file_scope (void)
 173 {
 174 }
 175
 176 void
 177 pop_file_scope (void)
 178 {
 179 }
 180
 181 /* c-pragma.c needs to query whether a decl has extern "C" linkage.  */
 182 bool
 183 has_c_linkage (const_tree decl)
 184 {
 185   return DECL_EXTERN_C_P (decl);
 186 }
 187
 188 static GTY ((if_marked ("tree_decl_map_marked_p"), param_is (struct tree_decl_map)))
 189      htab_t shadowed_var_for_decl;
 190
 191 /* Lookup a shadowed var for FROM, and return it if we find one.  */
 192
 193 tree
 194 decl_shadowed_for_var_lookup (tree from)
 195 {
 196   struct tree_decl_map *h, in;
 197   in.base.from = from;
 198
 199   h = (struct tree_decl_map *)
 200       htab_find_with_hash (shadowed_var_for_decl, &in, DECL_UID (from));
 201   if (h)
 202     return h->to;
 203   return NULL_TREE;
 204 }
 205
 206 /* Insert a mapping FROM->TO in the shadowed var hashtable.  */
 207
 208 void
 209 decl_shadowed_for_var_insert (tree from, tree to)
 210 {
 211   struct tree_decl_map *h;
 212   void **loc;
 213
 214   h = ggc_alloc_tree_decl_map ();
 215   h->base.from = from;
 216   h->to = to;
 217   loc = htab_find_slot_with_hash (shadowed_var_for_decl, h, DECL_UID (from),
 218                                   INSERT);
 219   *(struct tree_decl_map **) loc = h;
 220 }
 221
 222 void
 223 init_shadowed_var_for_decl (void)
 224 {
 225   shadowed_var_for_decl = htab_create_ggc (512, tree_decl_map_hash,
 226                                            tree_decl_map_eq, 0);
 227 }
 228
 229 /* Return true if stmt can fall thru.  Used by block_may_fallthru
 230    default case.  */
 231
 232 bool
 233 cxx_block_may_fallthru (const_tree stmt)
 234 {
 235   switch (TREE_CODE (stmt))
 236     {
 237     case EXPR_STMT:
 238       return block_may_fallthru (EXPR_STMT_EXPR (stmt));
 239
 240     case THROW_EXPR:
 241       return false;
 242
 243     default:
 244       return true;
 245     }
 246 }
 247
 248 void
 249 cp_common_init_ts (void)
 250 {
 251   MARK_TS_DECL_NON_COMMON (NAMESPACE_DECL);
 252   MARK_TS_DECL_NON_COMMON (USING_DECL);
 253   MARK_TS_DECL_NON_COMMON (TEMPLATE_DECL);
 254
 255   MARK_TS_COMMON (TEMPLATE_TEMPLATE_PARM);
 256   MARK_TS_COMMON (TEMPLATE_TYPE_PARM);
 257   MARK_TS_COMMON (TEMPLATE_PARM_INDEX);
 258   MARK_TS_COMMON (OVERLOAD);
 259   MARK_TS_COMMON (TEMPLATE_INFO);
 260   MARK_TS_COMMON (TYPENAME_TYPE);
 261   MARK_TS_COMMON (TYPEOF_TYPE);
 262   MARK_TS_COMMON (UNDERLYING_TYPE);
 263   MARK_TS_COMMON (BASELINK);
 264   MARK_TS_COMMON (TYPE_PACK_EXPANSION);
 265   MARK_TS_COMMON (TYPE_ARGUMENT_PACK);
 266   MARK_TS_COMMON (DECLTYPE_TYPE);
 267   MARK_TS_COMMON (BOUND_TEMPLATE_TEMPLATE_PARM);
 268   MARK_TS_COMMON (UNBOUND_CLASS_TEMPLATE);
 269
 270   MARK_TS_TYPED (EXPR_PACK_EXPANSION);
 271   MARK_TS_TYPED (SWITCH_STMT);
 272   MARK_TS_TYPED (IF_STMT);
 273   MARK_TS_TYPED (FOR_STMT);
 274   MARK_TS_TYPED (RANGE_FOR_STMT);
 275   MARK_TS_TYPED (AGGR_INIT_EXPR);
 276   MARK_TS_TYPED (EXPR_STMT);
 277   MARK_TS_TYPED (EH_SPEC_BLOCK);
 278   MARK_TS_TYPED (CLEANUP_STMT);
 279   MARK_TS_TYPED (SCOPE_REF);
 280   MARK_TS_TYPED (CAST_EXPR);
 281   MARK_TS_TYPED (NON_DEPENDENT_EXPR);
 282   MARK_TS_TYPED (MODOP_EXPR);
 283   MARK_TS_TYPED (TRY_BLOCK);
 284   MARK_TS_TYPED (THROW_EXPR);
 285   MARK_TS_TYPED (HANDLER);
 286   MARK_TS_TYPED (REINTERPRET_CAST_EXPR);
 287   MARK_TS_TYPED (CONST_CAST_EXPR);
 288   MARK_TS_TYPED (STATIC_CAST_EXPR);
 289   MARK_TS_TYPED (DYNAMIC_CAST_EXPR);
 290   MARK_TS_TYPED (IMPLICIT_CONV_EXPR);
 291   MARK_TS_TYPED (TEMPLATE_ID_EXPR);
 292   MARK_TS_TYPED (ARROW_EXPR);
 293   MARK_TS_TYPED (SIZEOF_EXPR);
 294   MARK_TS_TYPED (ALIGNOF_EXPR);
 295   MARK_TS_TYPED (AT_ENCODE_EXPR);
 296   MARK_TS_TYPED (UNARY_PLUS_EXPR);
 297   MARK_TS_TYPED (TRAIT_EXPR);
 298   MARK_TS_TYPED (TYPE_ARGUMENT_PACK);
 299   MARK_TS_TYPED (NOEXCEPT_EXPR);
 300   MARK_TS_TYPED (NONTYPE_ARGUMENT_PACK);
 301   MARK_TS_TYPED (WHILE_STMT);
 302   MARK_TS_TYPED (NEW_EXPR);
 303   MARK_TS_TYPED (VEC_NEW_EXPR);
 304   MARK_TS_TYPED (BREAK_STMT);
 305   MARK_TS_TYPED (MEMBER_REF);
 306   MARK_TS_TYPED (DOTSTAR_EXPR);
 307   MARK_TS_TYPED (DO_STMT);
 308   MARK_TS_TYPED (DELETE_EXPR);
 309   MARK_TS_TYPED (VEC_DELETE_EXPR);
 310   MARK_TS_TYPED (CONTINUE_STMT);
 311   MARK_TS_TYPED (TAG_DEFN);
 312   MARK_TS_TYPED (PSEUDO_DTOR_EXPR);
 313   MARK_TS_TYPED (TYPEID_EXPR);
 314   MARK_TS_TYPED (MUST_NOT_THROW_EXPR);
 315   MARK_TS_TYPED (STMT_EXPR);
 316   MARK_TS_TYPED (OFFSET_REF);
 317   MARK_TS_TYPED (OFFSETOF_EXPR);
 318   MARK_TS_TYPED (PTRMEM_CST);
 319   MARK_TS_TYPED (EMPTY_CLASS_EXPR);
 320   MARK_TS_TYPED (VEC_INIT_EXPR);
 321   MARK_TS_TYPED (USING_STMT);
 322   MARK_TS_TYPED (LAMBDA_EXPR);
 323   MARK_TS_TYPED (CTOR_INITIALIZER);
 324 }
 325
 326 #include "gt-cp-cp-objcp-common.h"