contrib/gcc-4.7/gcc/cp/cp-objcp-common.c

   1 /* Some code common to C++ and ObjC++ front ends.
   2    Copyright (C) 2004, 2007, 2008, 2009, 2010, 2011
   3    Free Software Foundation, Inc.
   4    Contributed by Ziemowit Laski  <zlaski@apple.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "tm.h"
  26 #include "tree.h"
  27 #include "cp-tree.h"
  28 #include "c-family/c-common.h"
  29 #include "langhooks.h"
  30 #include "langhooks-def.h"
  31 #include "diagnostic.h"
  32 #include "debug.h"
  33 #include "cxx-pretty-print.h"
  34 #include "cp-objcp-common.h"
  35
  36 /* Special routine to get the alias set for C++.  */
  37
  38 alias_set_type
  39 cxx_get_alias_set (tree t)
  40 {
  41   if (IS_FAKE_BASE_TYPE (t))
  42     /* The base variant of a type must be in the same alias set as the
  43        complete type.  */
  44     return get_alias_set (TYPE_CONTEXT (t));
  45
  46   /* Punt on PMFs until we canonicalize functions properly.  */
  47   if (TYPE_PTRMEMFUNC_P (t)
  48       || (POINTER_TYPE_P (t)
  49           && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))))
  50     return 0;
  51
  52   return c_common_get_alias_set (t);
  53 }
  54
  55 /* Called from check_global_declarations.  */
  56
  57 bool
  58 cxx_warn_unused_global_decl (const_tree decl)
  59 {
  60   if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl))
  61     return false;
  62   if (DECL_IN_SYSTEM_HEADER (decl))
  63     return false;
  64
  65   /* Const variables take the place of #defines in C++.  */
  66   if (TREE_CODE (decl) == VAR_DECL && TREE_READONLY (decl))
  67     return false;
  68
  69   return true;
  70 }
  71
  72 /* Langhook for tree_size: determine size of our 'x' and 'c' nodes.  */
  73 size_t
  74 cp_tree_size (enum tree_code code)
  75 {
  76   switch (code)
  77     {
  78     case PTRMEM_CST:            return sizeof (struct ptrmem_cst);
  79     case BASELINK:              return sizeof (struct tree_baselink);
  80     case TEMPLATE_PARM_INDEX:   return sizeof (template_parm_index);
  81     case DEFAULT_ARG:           return sizeof (struct tree_default_arg);
  82     case DEFERRED_NOEXCEPT:     return sizeof (struct tree_deferred_noexcept);
  83     case OVERLOAD:              return sizeof (struct tree_overload);
  84     case STATIC_ASSERT:         return sizeof (struct tree_static_assert);
  85     case TYPE_ARGUMENT_PACK:
  86     case TYPE_PACK_EXPANSION:
  87       return sizeof (struct tree_common);
  88
  89     case NONTYPE_ARGUMENT_PACK:
  90     case EXPR_PACK_EXPANSION:
  91       return sizeof (struct tree_exp);
  92
  93     case ARGUMENT_PACK_SELECT:
  94       return sizeof (struct tree_argument_pack_select);
  95
  96     case TRAIT_EXPR:
  97       return sizeof (struct tree_trait_expr);
  98
  99     case LAMBDA_EXPR:           return sizeof (struct tree_lambda_expr);
 100
 101     case TEMPLATE_INFO:         return sizeof (struct tree_template_info);
 102
 103     case USERDEF_LITERAL:       return sizeof (struct tree_userdef_literal);
 104
 105     default:
 106       gcc_unreachable ();
 107     }
 108   /* NOTREACHED */
 109 }
 110
 111 /* Returns true if T is a variably modified type, in the sense of C99.
 112    FN is as passed to variably_modified_p.
 113    This routine needs only check cases that cannot be handled by the
 114    language-independent logic in tree.c.  */
 115
 116 bool
 117 cp_var_mod_type_p (tree type, tree fn)
 118 {
 119   /* If TYPE is a pointer-to-member, it is variably modified if either
 120      the class or the member are variably modified.  */
 121   if (TYPE_PTR_TO_MEMBER_P (type))
 122     return (variably_modified_type_p (TYPE_PTRMEM_CLASS_TYPE (type), fn)
 123             || variably_modified_type_p (TYPE_PTRMEM_POINTED_TO_TYPE (type),
 124                                          fn));
 125
 126   /* All other types are not variably modified.  */
 127   return false;
 128 }
 129
 130 /* Construct a C++-aware pretty-printer for CONTEXT.  It is assumed
 131    that CONTEXT->printer is an already constructed basic pretty_printer.  */
 132 void
 133 cxx_initialize_diagnostics (diagnostic_context *context)
 134 {
 135   pretty_printer *base;
 136   cxx_pretty_printer *pp;
 137
 138   c_common_initialize_diagnostics (context);
 139
 140   base = context->printer;
 141   pp = XNEW (cxx_pretty_printer);
 142   memcpy (pp_base (pp), base, sizeof (pretty_printer));
 143   pp_cxx_pretty_printer_init (pp);
 144   context->printer = (pretty_printer *) pp;
 145
 146   /* It is safe to free this object because it was previously malloc()'d.  */
 147   free (base);
 148 }
 149
 150 /* This compares two types for equivalence ("compatible" in C-based languages).
 151    This routine should only return 1 if it is sure.  It should not be used
 152    in contexts where erroneously returning 0 causes problems.  */
 153
 154 int
 155 cxx_types_compatible_p (tree x, tree y)
 156 {
 157   return same_type_ignoring_top_level_qualifiers_p (x, y);
 158 }
 159
 160 /* Return true if DECL is explicit member function.  */
 161
 162 bool
 163 cp_function_decl_explicit_p (tree decl)
 164 {
 165   return (decl
 166           && FUNCTION_FIRST_USER_PARMTYPE (decl) != void_list_node
 167           && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl))
 168           && DECL_NONCONVERTING_P (decl));
 169 }
 170
 171 /* Stubs to keep c-opts.c happy.  */
 172 void
 173 push_file_scope (void)
 174 {
 175 }
 176
 177 void
 178 pop_file_scope (void)
 179 {
 180 }
 181
 182 /* c-pragma.c needs to query whether a decl has extern "C" linkage.  */
 183 bool
 184 has_c_linkage (const_tree decl)
 185 {
 186   return DECL_EXTERN_C_P (decl);
 187 }
 188
 189 static GTY ((if_marked ("tree_decl_map_marked_p"), param_is (struct tree_decl_map)))
 190      htab_t shadowed_var_for_decl;
 191
 192 /* Lookup a shadowed var for FROM, and return it if we find one.  */
 193
 194 tree
 195 decl_shadowed_for_var_lookup (tree from)
 196 {
 197   struct tree_decl_map *h, in;
 198   in.base.from = from;
 199
 200   h = (struct tree_decl_map *)
 201       htab_find_with_hash (shadowed_var_for_decl, &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   void **loc;
 214
 215   h = ggc_alloc_tree_decl_map ();
 216   h->base.from = from;
 217   h->to = to;
 218   loc = htab_find_slot_with_hash (shadowed_var_for_decl, h, DECL_UID (from),
 219                                   INSERT);
 220   *(struct tree_decl_map **) loc = h;
 221 }
 222
 223 void
 224 init_shadowed_var_for_decl (void)
 225 {
 226   shadowed_var_for_decl = htab_create_ggc (512, tree_decl_map_hash,
 227                                            tree_decl_map_eq, 0);
 228 }
 229
 230 /* Return true if stmt can fall thru.  Used by block_may_fallthru
 231    default case.  */
 232
 233 bool
 234 cxx_block_may_fallthru (const_tree stmt)
 235 {
 236   switch (TREE_CODE (stmt))
 237     {
 238     case EXPR_STMT:
 239       return block_may_fallthru (EXPR_STMT_EXPR (stmt));
 240
 241     case THROW_EXPR:
 242       return false;
 243
 244     default:
 245       return true;
 246     }
 247 }
 248
 249 void
 250 cp_common_init_ts (void)
 251 {
 252   MARK_TS_DECL_NON_COMMON (NAMESPACE_DECL);
 253   MARK_TS_DECL_NON_COMMON (USING_DECL);
 254   MARK_TS_DECL_NON_COMMON (TEMPLATE_DECL);
 255
 256   MARK_TS_COMMON (TEMPLATE_TEMPLATE_PARM);
 257   MARK_TS_COMMON (TEMPLATE_TYPE_PARM);
 258   MARK_TS_COMMON (TEMPLATE_PARM_INDEX);
 259   MARK_TS_COMMON (OVERLOAD);
 260   MARK_TS_COMMON (TEMPLATE_INFO);
 261   MARK_TS_COMMON (TYPENAME_TYPE);
 262   MARK_TS_COMMON (TYPEOF_TYPE);
 263   MARK_TS_COMMON (UNDERLYING_TYPE);
 264   MARK_TS_COMMON (BASELINK);
 265   MARK_TS_COMMON (TYPE_PACK_EXPANSION);
 266   MARK_TS_COMMON (TYPE_ARGUMENT_PACK);
 267   MARK_TS_COMMON (DECLTYPE_TYPE);
 268   MARK_TS_COMMON (BOUND_TEMPLATE_TEMPLATE_PARM);
 269   MARK_TS_COMMON (UNBOUND_CLASS_TEMPLATE);
 270
 271   MARK_TS_TYPED (EXPR_PACK_EXPANSION);
 272   MARK_TS_TYPED (SWITCH_STMT);
 273   MARK_TS_TYPED (IF_STMT);
 274   MARK_TS_TYPED (FOR_STMT);
 275   MARK_TS_TYPED (RANGE_FOR_STMT);
 276   MARK_TS_TYPED (AGGR_INIT_EXPR);
 277   MARK_TS_TYPED (EXPR_STMT);
 278   MARK_TS_TYPED (EH_SPEC_BLOCK);
 279   MARK_TS_TYPED (CLEANUP_STMT);
 280   MARK_TS_TYPED (SCOPE_REF);
 281   MARK_TS_TYPED (CAST_EXPR);
 282   MARK_TS_TYPED (NON_DEPENDENT_EXPR);
 283   MARK_TS_TYPED (MODOP_EXPR);
 284   MARK_TS_TYPED (TRY_BLOCK);
 285   MARK_TS_TYPED (THROW_EXPR);
 286   MARK_TS_TYPED (HANDLER);
 287   MARK_TS_TYPED (REINTERPRET_CAST_EXPR);
 288   MARK_TS_TYPED (CONST_CAST_EXPR);
 289   MARK_TS_TYPED (STATIC_CAST_EXPR);
 290   MARK_TS_TYPED (DYNAMIC_CAST_EXPR);
 291   MARK_TS_TYPED (IMPLICIT_CONV_EXPR);
 292   MARK_TS_TYPED (TEMPLATE_ID_EXPR);
 293   MARK_TS_TYPED (ARROW_EXPR);
 294   MARK_TS_TYPED (SIZEOF_EXPR);
 295   MARK_TS_TYPED (ALIGNOF_EXPR);
 296   MARK_TS_TYPED (AT_ENCODE_EXPR);
 297   MARK_TS_TYPED (UNARY_PLUS_EXPR);
 298   MARK_TS_TYPED (TRAIT_EXPR);
 299   MARK_TS_TYPED (TYPE_ARGUMENT_PACK);
 300   MARK_TS_TYPED (NOEXCEPT_EXPR);
 301   MARK_TS_TYPED (NONTYPE_ARGUMENT_PACK);
 302   MARK_TS_TYPED (WHILE_STMT);
 303   MARK_TS_TYPED (NEW_EXPR);
 304   MARK_TS_TYPED (VEC_NEW_EXPR);
 305   MARK_TS_TYPED (BREAK_STMT);
 306   MARK_TS_TYPED (MEMBER_REF);
 307   MARK_TS_TYPED (DOTSTAR_EXPR);
 308   MARK_TS_TYPED (DO_STMT);
 309   MARK_TS_TYPED (DELETE_EXPR);
 310   MARK_TS_TYPED (VEC_DELETE_EXPR);
 311   MARK_TS_TYPED (CONTINUE_STMT);
 312   MARK_TS_TYPED (TAG_DEFN);
 313   MARK_TS_TYPED (PSEUDO_DTOR_EXPR);
 314   MARK_TS_TYPED (TYPEID_EXPR);
 315   MARK_TS_TYPED (MUST_NOT_THROW_EXPR);
 316   MARK_TS_TYPED (STMT_EXPR);
 317   MARK_TS_TYPED (OFFSET_REF);
 318   MARK_TS_TYPED (OFFSETOF_EXPR);
 319   MARK_TS_TYPED (PTRMEM_CST);
 320   MARK_TS_TYPED (EMPTY_CLASS_EXPR);
 321   MARK_TS_TYPED (VEC_INIT_EXPR);
 322   MARK_TS_TYPED (USING_STMT);
 323   MARK_TS_TYPED (LAMBDA_EXPR);
 324   MARK_TS_TYPED (CTOR_INITIALIZER);
 325 }
 326
 327 #include "gt-cp-cp-objcp-common.h"