+2004-07-02 Zack Weinberg <zack@codesourcery.com>
+
+ * c-decl.c (struct c_binding): Remove contour field; add
+ depth, invisible, nested fields.
+ (B_IN_SCOPE, B_IN_CURRENT_SCOPE, B_IN_FILE_SCOPE)
+ (B_IN_EXTERNAL_SCOPE): New convenience macros.
+ (bind): Add invisible and nested arguments. Initialize
+ new fields of struct c_binding; adjust loop scanning for
+ insertion point.
+ (free_binding_and_advance): Clear structure with memset.
+ (pop_scope): Adjust to match. Set DECL_CONTEXT on everything
+ in file scope, even if it's in external scope too.
+ (pushdecl): Adjust to match. Create invisible file-scope
+ declarations for block-scope forward declarations of static functions.
+ (pushtag, warn_if_shadowing, pushdecl_top_level, implicitly_declare)
+ (undeclared_variable, lookup_label, declare_label, define_label)
+ (lookup_tag, lookup_name, lookup_name_in_scope, builtin_function)
+ (c_make_fname_decl, store_parm_decls_newstyle, identifier_global_value)
+ (store_parm_decls_oldstyle): Adjust to match.
+ (diagnose_mismatched_decls): Correct handling of linkage clashes.
+ (merge_decls): No need to copy C_DECL_IN_EXTERNAL_SCOPE.
+
+ * c-tree.h (C_DECL_IN_EXTERNAL_SCOPE): Delete.
+ (C_DECL_DECLARED_BUILTIN, C_DECL_REGISTER): Slide down one.
+
2004-07-02 Richard Henderson <rth@redhat.com>
* c-decl.c (grokdeclarator): Don't frob current_function_decl
* c-typeck.c (lvalue_p): Don't handle it.
* expr.c (safe_from_p): Likewise.
(expand_expr_real_1): Likewise.
- * fold-const.c (non_lvalue, operand_equal_p, fold): Likewise.
+ * fold-const.c (non_lvalue, operand_equal_p, fold): Likewise.
(fold_checksum_tree, tree_expr_nonnegative_p): Likewise.
* gengtype.c (adjust_field_tree_exp): Likewise.
* stmt.c (warn_if_unused_value): Likewise.
* builtins.c (expand_builtin_prefetch, expand_builtin_profile_func,
expand_builtin): Likewise.
* calls.c (expand_call, emit_library_call_value_1, store_one_arg):
- Likewise.
+ Likewise.
* combine.c (can_combine_p, combinable_i3pat, try_combine,
find_split_point, combine_simplify_rtx, simplify_set, make_extraction,
rtx_equal_for_field_assignment_p, gen_lowpart_for_combine,
emit_move_insn_1, expand_assignment, store_expr,
store_constructor_field, store_constructor, store_field,
force_operand, safe_from_p, expand_expr_real_1, expand_increment):
- Likewise.
+ Likewise.
* final.c (cleanup_subreg_operands, alter_subreg,
get_mem_expr_from_op): Likewise.
* flow.c (notice_stack_pointer_modification_1,
init_propagate_block_info, insn_dead_p, mark_set_1, mark_used_regs):
- Likewise.
+ Likewise.
* function.c (mark_temp_addr_taken, preserve_temp_slots,
preserve_rtl_expr_result, put_var_into_stack, fixup_var_refs_1,
optimize_bit_field, flush_addressof, purge_addressof_1,
import_export_class.
* target-def.h (TARGET_CXX): Initialise the new field.
(TARGET_CXX_IMPORT_EXPORT_CLASS): Provide a default value for
- the new field.
+ the new field.
* doc/tm.texi: Document the new target hook.
2004-07-01 Paolo Bonzini <bonzini@gnu.org>
chained together by the ->prev field, which (as the name implies)
runs in reverse order. All the decls in a given namespace bound to
a given identifier are chained by the ->shadowed field, which runs
- from inner to outer scopes. Finally, the ->contour field points
- back to the relevant scope structure; this is mainly used to make
- decls in the externals scope invisible (see below).
+ from inner to outer scopes.
The ->decl field usually points to a DECL node, but there are two
exceptions. In the namespace of type tags, the bound entity is a
RECORD_TYPE, UNION_TYPE, or ENUMERAL_TYPE node. If an undeclared
identifier is encountered, it is bound to error_mark_node to
suppress further errors about that identifier in the current
- function. */
+ function.
+
+ The depth field is copied from the scope structure that holds this
+ decl. It is used to preserve the proper ordering of the ->shadowed
+ field (see bind()) and also for a handful of special-case checks.
+ Finally, the invisible bit is true for a decl which should be
+ ignored for purposes of normal name lookup, and the nested bit is
+ true for a decl that's been bound a second time in an inner scope;
+ in all such cases, the binding in the outer scope will have its
+ invisible bit true. */
struct c_binding GTY((chain_next ("%h.prev")))
{
tree id; /* the identifier it's bound to */
struct c_binding *prev; /* the previous decl in this scope */
struct c_binding *shadowed; /* the innermost decl shadowed by this one */
- struct c_scope *contour; /* the scope in which this decl is bound */
+ unsigned int depth : 28; /* depth of this scope */
+ BOOL_BITFIELD invisible : 1; /* normal lookup should ignore this binding */
+ BOOL_BITFIELD nested : 1; /* do not set DECL_CONTEXT when popping */
+ /* two free bits */
};
+#define B_IN_SCOPE(b1, b2) ((b1)->depth == (b2)->depth)
+#define B_IN_CURRENT_SCOPE(b) ((b)->depth == current_scope->depth)
+#define B_IN_FILE_SCOPE(b) ((b)->depth == 1 /*file_scope->depth*/)
+#define B_IN_EXTERNAL_SCOPE(b) ((b)->depth == 0 /*external_scope->depth*/)
#define I_SYMBOL_BINDING(node) \
(((struct lang_identifier *)IDENTIFIER_NODE_CHECK(node))->symbol_binding)
which may be any of several kinds of DECL or TYPE or error_mark_node,
in the scope SCOPE. */
static void
-bind (tree name, tree decl, struct c_scope *scope)
+bind (tree name, tree decl, struct c_scope *scope, bool invisible, bool nested)
{
struct c_binding *b, **here;
b->shadowed = 0;
b->decl = decl;
b->id = name;
- b->contour = scope;
+ b->depth = scope->depth;
+ b->invisible = invisible;
+ b->nested = nested;
b->prev = scope->bindings;
scope->bindings = b;
/* Locate the appropriate place in the chain of shadowed decls
to insert this binding. Normally, scope == current_scope and
this does nothing. */
- while (*here && (*here)->contour->depth > scope->depth)
+ while (*here && (*here)->depth > scope->depth)
here = &(*here)->shadowed;
b->shadowed = *here;
{
struct c_binding *prev = b->prev;
- b->id = 0;
- b->decl = 0;
- b->contour = 0;
- b->shadowed = 0;
+ memset (b, 0, sizeof (struct c_binding));
b->prev = binding_freelist;
binding_freelist = b;
common_symbol:
/* All of these go in BLOCK_VARS, but only if this is the
binding in the home scope. */
- if (!C_DECL_IN_EXTERNAL_SCOPE (p) || scope == external_scope)
+ if (!b->nested)
{
TREE_CHAIN (p) = BLOCK_VARS (block);
BLOCK_VARS (block) = p;
}
- /* If this is the file scope, must set DECL_CONTEXT on these. */
- if (!C_DECL_IN_EXTERNAL_SCOPE (p) && scope == file_scope)
+ /* If this is the file scope, must set DECL_CONTEXT on
+ these. Do so even for externals, so that
+ same_translation_unit_p works. */
+ if (scope == file_scope)
DECL_CONTEXT (p) = context;
/* Fall through. */
start_fname_decls ();
for (decl = visible_builtins; decl; decl = TREE_CHAIN (decl))
- bind (DECL_NAME (decl), decl, file_scope);
+ bind (DECL_NAME (decl), decl, file_scope,
+ /*invisible=*/false, /*nested=*/true);
}
void
/* Record the identifier as the type's name if it has none. */
if (name && !TYPE_NAME (type))
TYPE_NAME (type) = name;
- bind (name, type, current_scope);
+ bind (name, type, current_scope, /*invisible=*/false, /*nested=*/false);
/* Create a fake NULL-named TYPE_DECL node whose TREE_TYPE will be the
tagged type we just added to the current scope. This fake
locate_old_decl (olddecl, error);
return false;
}
- /* Mismatched non-static and static is considered poor style.
- We only diagnose static then non-static if -Wtraditional,
- because it is the most convenient way to get some effects
- (see e.g. what unwind-dw2-fde-glibc.c does to the definition
- of _Unwind_Find_FDE in unwind-dw2-fde.c). Revisit? */
+ /* A non-static declaration (even an "extern") followed by a
+ static declaration is undefined behavior per C99 6.2.2p3-5,7.
+ The same is true for a static forward declaration at block
+ scope followed by a non-static declaration/definition at file
+ scope. Static followed by non-static at the same scope is
+ not undefined behavior, and is the most convenient way to get
+ some effects (see e.g. what unwind-dw2-fde-glibc.c does to
+ the definition of _Unwind_Find_FDE in unwind-dw2-fde.c), but
+ we do diagnose it if -Wtraditional. */
if (TREE_PUBLIC (olddecl) && !TREE_PUBLIC (newdecl))
{
- /* A static function declaration for a predeclared function
- that isn't actually built in, silently overrides the
- default. Objective C uses these. See also above.
- FIXME: Make Objective C use normal builtins. */
- if (TREE_CODE (olddecl) == FUNCTION_DECL
- && DECL_IS_BUILTIN (olddecl))
- return false;
- else
+ /* Two exceptions to the rule. If olddecl is an extern
+ inline, or a predeclared function that isn't actually
+ built in, newdecl silently overrides olddecl. The latter
+ occur only in Objective C; see also above. (FIXME: Make
+ Objective C use normal builtins.) */
+ if (!DECL_IS_BUILTIN (olddecl)
+ && !(DECL_EXTERNAL (olddecl)
+ && DECL_DECLARED_INLINE_P (olddecl)))
{
- warning ("%Jstatic declaration of '%D' follows "
- "non-static declaration", newdecl, newdecl);
- warned = true;
+ error ("%Jstatic declaration of '%D' follows "
+ "non-static declaration", newdecl, newdecl);
+ locate_old_decl (olddecl, error);
}
+ return false;
}
- else if (TREE_PUBLIC (newdecl) && !TREE_PUBLIC (olddecl)
- && warn_traditional)
+ else if (TREE_PUBLIC (newdecl) && !TREE_PUBLIC (olddecl))
{
- warning ("%Jnon-static declaration of '%D' follows "
- "static declaration", newdecl, newdecl);
- warned = true;
+ if (DECL_CONTEXT (olddecl))
+ {
+ error ("%Jnon-static declaration of '%D' follows "
+ "static declaration", newdecl, newdecl);
+ locate_old_decl (olddecl, error);
+ return false;
+ }
+ else if (warn_traditional)
+ {
+ warning ("%Jnon-static declaration of '%D' follows "
+ "static declaration", newdecl, newdecl);
+ warned = true;
+ }
}
}
else if (TREE_CODE (newdecl) == VAR_DECL)
return false;
}
- /* Objects declared at file scope: if at least one is 'extern',
- it's fine (6.2.2p4); otherwise the linkage must agree (6.2.2p7). */
- if (DECL_FILE_SCOPE_P (newdecl))
+ /* Objects declared at file scope: if the first declaration had
+ external linkage (even if it was an external reference) the
+ second must have external linkage as well, or the behavior is
+ undefined. If the first declaration had internal linkage, then
+ the second must too, or else be an external reference (in which
+ case the composite declaration still has internal linkage).
+ As for function declarations, we warn about the static-then-
+ extern case only for -Wtraditional. See generally 6.2.2p3-5,7. */
+ if (DECL_FILE_SCOPE_P (newdecl)
+ && TREE_PUBLIC (newdecl) != TREE_PUBLIC (olddecl))
{
- if (!DECL_EXTERNAL (newdecl)
- && !DECL_EXTERNAL (olddecl)
- && TREE_PUBLIC (newdecl) != TREE_PUBLIC (olddecl))
+ if (DECL_EXTERNAL (newdecl))
+ {
+ if (warn_traditional)
+ {
+ warning ("%Jnon-static declaration of '%D' follows "
+ "static declaration", newdecl, newdecl);
+ warned = true;
+ }
+ }
+ else
{
if (TREE_PUBLIC (newdecl))
error ("%Jnon-static declaration of '%D' follows "
}
/* Two objects with the same name declared at the same block
scope must both be external references (6.7p3). */
- else if (DECL_CONTEXT (newdecl) == DECL_CONTEXT (olddecl)
+ else if (!DECL_FILE_SCOPE_P (newdecl)
+ && DECL_CONTEXT (newdecl) == DECL_CONTEXT (olddecl)
&& (!DECL_EXTERNAL (newdecl) || !DECL_EXTERNAL (olddecl)))
{
if (DECL_EXTERNAL (newdecl))
}
}
- /* This bit must not get wiped out. */
- C_DECL_IN_EXTERNAL_SCOPE (newdecl) |= C_DECL_IN_EXTERNAL_SCOPE (olddecl);
-
/* Copy most of the decl-specific fields of NEWDECL into OLDDECL.
But preserve OLDDECL's DECL_UID. */
{
|| (TREE_CODE (new) == PARM_DECL && current_scope->outer->parm_flag))
return;
- /* Is anything being shadowed? Do not be confused by a second binding
- to the same decl in the externals scope. */
+ /* Is anything being shadowed? Invisible decls do not count. */
for (b = I_SYMBOL_BINDING (DECL_NAME (new)); b; b = b->shadowed)
- if (b->decl && b->decl != new && b->contour != external_scope)
+ if (b->decl && b->decl != new && !b->invisible)
{
tree old = b->decl;
tree name = DECL_NAME (x);
struct c_scope *scope = current_scope;
struct c_binding *b;
+ bool nested = false;
/* Functions need the lang_decl data. */
if (TREE_CODE (x) == FUNCTION_DECL && ! DECL_LANG_SPECIFIC (x))
/* Anonymous decls are just inserted in the scope. */
if (!name)
{
- bind (name, x, scope);
+ bind (name, x, scope, /*invisible=*/false, /*nested=*/false);
return x;
}
diagnostics). In particular, we should not consider possible
duplicates in the external scope, or shadowing. */
b = I_SYMBOL_BINDING (name);
- if (b && b->contour == scope)
+ if (b && B_IN_SCOPE (b, scope))
{
if (duplicate_decls (x, b->decl))
return b->decl;
if (warn_nested_externs
&& scope != file_scope
&& !DECL_IN_SYSTEM_HEADER (x))
- warning ("nested extern declaration of `%s'",
- IDENTIFIER_POINTER (name));
+ warning ("nested extern declaration of '%D'", x);
- while (b && b->contour != external_scope)
+ while (b && !B_IN_EXTERNAL_SCOPE (b))
b = b->shadowed;
/* The point of the same_translation_unit_p check here is,
|| same_translation_unit_p (x, b->decl))
&& duplicate_decls (x, b->decl))
{
- bind (name, b->decl, scope);
+ bind (name, b->decl, scope, /*invisible=*/false, /*nested=*/true);
return b->decl;
}
else if (DECL_EXTERNAL (x) || TREE_PUBLIC (x))
{
- C_DECL_IN_EXTERNAL_SCOPE (x) = 1;
- bind (name, x, external_scope);
+ bind (name, x, external_scope, /*invisible=*/true, /*nested=*/false);
+ nested = true;
}
}
+ /* Similarly, a declaration of a function with static linkage at
+ block scope must be checked against any existing declaration
+ of that function at file scope. */
+ else if (TREE_CODE (x) == FUNCTION_DECL && scope != file_scope
+ && !TREE_PUBLIC (x) && !DECL_INITIAL (x))
+ {
+ if (warn_nested_externs && !DECL_IN_SYSTEM_HEADER (x))
+ warning ("nested static declaration of '%D'", x);
+
+ while (b && !B_IN_FILE_SCOPE (b))
+ b = b->shadowed;
+
+ if (b && same_translation_unit_p (x, b->decl)
+ && duplicate_decls (x, b->decl))
+ {
+ bind (name, b->decl, scope, /*invisible=*/false, /*nested=*/true);
+ return b->decl;
+ }
+ else
+ {
+ bind (name, x, file_scope, /*invisible=*/true, /*nested=*/false);
+ nested = true;
+ }
+ }
warn_if_shadowing (x);
if (TREE_CODE (x) == TYPE_DECL)
clone_underlying_type (x);
- bind (name, x, scope);
+ bind (name, x, scope, /*invisible=*/false, nested);
/* If x's type is incomplete because it's based on a
structure or union which has not yet been fully declared,
pushdecl_top_level (tree x)
{
tree name;
+ bool nested = false;
if (TREE_CODE (x) != VAR_DECL)
abort ();
if (DECL_EXTERNAL (x) || TREE_PUBLIC (x))
{
- C_DECL_IN_EXTERNAL_SCOPE (x) = 1;
- bind (name, x, external_scope);
+ bind (name, x, external_scope, /*invisible=*/true, /*nested=*/false);
+ nested = true;
}
if (file_scope)
- bind (name, x, file_scope);
+ bind (name, x, file_scope, /*invisible=*/false, nested);
return x;
}
file scope. */
if (!DECL_BUILT_IN (decl) && DECL_IS_BUILTIN (decl))
{
- bind (functionid, decl, file_scope);
+ bind (functionid, decl, file_scope,
+ /*invisible=*/false, /*nested=*/true);
return decl;
}
else
implicit_decl_warning (functionid, decl);
C_DECL_IMPLICIT (decl) = 1;
}
- bind (functionid, decl, current_scope);
+ bind (functionid, decl, current_scope,
+ /*invisible=*/false, /*nested=*/true);
return decl;
}
}
will be nonnull but current_function_scope will be null. */
scope = current_function_scope ? current_function_scope : current_scope;
}
- bind (id, error_mark_node, scope);
+ bind (id, error_mark_node, scope, /*invisible=*/false, /*nested=*/false);
}
\f
/* Subroutine of lookup_label, declare_label, define_label: construct a
label = make_label (name, input_location);
/* Ordinary labels go in the current function scope. */
- bind (name, label, current_function_scope);
+ bind (name, label, current_function_scope,
+ /*invisible=*/false, /*nested=*/false);
return label;
}
/* Check to make sure that the label hasn't already been declared
at this scope */
- if (b && b->contour == current_scope)
+ if (b && B_IN_CURRENT_SCOPE (b))
{
error ("duplicate label declaration `%s'", IDENTIFIER_POINTER (name));
locate_old_decl (b->decl, error);
C_DECLARED_LABEL_FLAG (label) = 1;
/* Declared labels go in the current scope. */
- bind (name, label, current_scope);
+ bind (name, label, current_scope,
+ /*invisible=*/false, /*nested=*/false);
return label;
}
label = make_label (name, location);
/* Ordinary labels go in the current function scope. */
- bind (name, label, current_function_scope);
+ bind (name, label, current_function_scope,
+ /*invisible=*/false, /*nested=*/false);
}
if (warn_traditional && !in_system_header && lookup_name (name))
a tag in the file scope. (Primarily relevant to Objective-C
and its builtin structure tags, which get pushed before the
file scope is created.) */
- if (b->contour == current_scope
- || (current_scope == file_scope && b->contour == external_scope))
+ if (B_IN_CURRENT_SCOPE (b)
+ || (current_scope == file_scope && B_IN_EXTERNAL_SCOPE (b)))
thislevel = 1;
}
lookup_name (tree name)
{
struct c_binding *b = I_SYMBOL_BINDING (name);
- if (b && (b->contour != external_scope || TREE_CODE (b->decl) == TYPE_DECL))
+ if (b && !b->invisible)
return b->decl;
return 0;
}
struct c_binding *b;
for (b = I_SYMBOL_BINDING (name); b; b = b->shadowed)
- if (b->contour == scope)
+ if (B_IN_SCOPE (b, scope))
return b->decl;
return 0;
}
if (current_function_decl)
{
DECL_CONTEXT (decl) = current_function_decl;
- bind (id, decl, current_function_scope);
+ bind (id, decl, current_function_scope,
+ /*invisible=*/false, /*nested=*/false);
}
finish_decl (decl, init, NULL_TREE);
if (I_SYMBOL_BINDING (id))
abort ();
- C_DECL_IN_EXTERNAL_SCOPE (decl) = 1;
- bind (id, decl, external_scope);
+ bind (id, decl, external_scope, /*invisible=*/true, /*nested=*/false);
/* Builtins in the implementation namespace are made visible without
needing to be explicitly declared. See push_file_scope. */
{
DECL_CONTEXT (decl) = current_function_decl;
if (DECL_NAME (decl))
- bind (DECL_NAME (decl), decl, current_scope);
+ bind (DECL_NAME (decl), decl, current_scope,
+ /*invisible=*/false, /*nested=*/false);
else
error ("%Jparameter name omitted", decl);
}
{
DECL_CONTEXT (decl) = current_function_decl;
if (DECL_NAME (decl))
- bind (DECL_NAME (decl), decl, current_scope);
+ bind (DECL_NAME (decl), decl, current_scope,
+ /*invisible=*/false, /*nested=*/false);
}
/* And all the tag declarations. */
for (decl = tags; decl; decl = TREE_CHAIN (decl))
if (TREE_PURPOSE (decl))
- bind (TREE_PURPOSE (decl), TREE_VALUE (decl), current_scope);
+ bind (TREE_PURPOSE (decl), TREE_VALUE (decl), current_scope,
+ /*invisible=*/false, /*nested=*/false);
}
/* Subroutine of store_parm_decls which handles old-style function
}
b = I_SYMBOL_BINDING (TREE_VALUE (parm));
- if (b && b->contour == current_scope)
+ if (b && B_IN_CURRENT_SCOPE (b))
{
decl = b->decl;
/* If we got something other than a PARM_DECL it is an error. */
struct c_binding *b;
for (b = I_SYMBOL_BINDING (t); b; b = b->shadowed)
- if (b->contour == file_scope || b->contour == external_scope)
+ if (B_IN_FILE_SCOPE (b) || B_IN_EXTERNAL_SCOPE (b))
return b->decl;
return 0;
projects / gcc.git / commitdiff