- replaced set_scope by scope_push()/scope_pop()

- detect access to variables of outer functions and set the address_taken flag
- detect redeclaration of parameters and issue an error
- set last_declaration in the parameter scope
- mark the scope of parameters

[r22060]

diff --git a/ast_t.h b/ast_t.h
index 360b35b..79e75b1 100644 (file)
--- a/ast_t.h
+++ b/ast_t.h
@@ -189,6 +189,9 @@ typedef enum funcname_kind_t {
 struct scope_t {
        declaration_t *declarations;      /**< List of declarations in this scope. */
        declaration_t *last_declaration;  /**< last declaration in this scope. */
+       scope_t       *parent;            /**< points to the parent scope. */
+       unsigned      depth;              /**< while parsing, the depth of this scope in the scope stack. */
+       bool          is_parameter;       /**< Set if this scope is a parameter scope. */
 };
 
 struct expression_base_t {

diff --git a/parser.c b/parser.c
index 68e6670..f3b6082 100644 (file)
--- a/parser.c
+++ b/parser.c
@@ -114,9 +114,12 @@ static int                 lookahead_bufpos;
 static stack_entry_t      *environment_stack = NULL;
 static stack_entry_t      *label_stack       = NULL;
 static stack_entry_t      *local_label_stack = NULL;
+/** The global file scope. */
 static scope_t            *global_scope      = NULL;
+/** The current scope. */
 static scope_t            *scope             = NULL;
 static declaration_t      *last_declaration  = NULL;
+/** Point to the current function declaration if inside a function. */
 static declaration_t      *current_function  = NULL;
 static declaration_t      *current_init_decl = NULL;
 static switch_statement_t *current_switch    = NULL;
@@ -713,16 +716,25 @@ static void type_error_incompatible(const char *msg,
                next_token();                                     \
        } while (0)
 
-static void set_scope(scope_t *new_scope)
+static void scope_push(scope_t *new_scope)
 {
        if (scope != NULL) {
                scope->last_declaration = last_declaration;
+               new_scope->depth        = scope->depth + 1;
        }
-       scope = new_scope;
+       new_scope->parent = scope;
+       scope             = new_scope;
 
        last_declaration = new_scope->last_declaration;
 }
 
+static void scope_pop(void)
+{
+       scope->last_declaration = last_declaration;
+       scope = scope->parent;
+       last_declaration = scope->last_declaration;
+}
+
 /**
  * Search a symbol in a given namespace and returns its declaration or
  * NULL if this symbol was not found.
@@ -3674,7 +3686,13 @@ static type_qualifiers_t parse_type_qualifiers(void)
        }
 }
 
-static declaration_t *parse_identifier_list(void)
+/**
+ * Parses an K&R identifier list and return a list of declarations.
+ *
+ * @param last  points to the last declaration in the list
+ * @return the list of declarations
+ */
+static declaration_t *parse_identifier_list(declaration_t **last)
 {
        declaration_t *declarations     = NULL;
        declaration_t *last_declaration = NULL;
@@ -3698,6 +3716,7 @@ static declaration_t *parse_identifier_list(void)
                next_token();
        } while (token.type == T_IDENTIFIER);
 
+       *last = last_declaration;
        return declarations;
 }
 
@@ -3750,7 +3769,13 @@ static declaration_t *parse_parameter(void)
        return declaration;
 }
 
-static declaration_t *parse_parameters(function_type_t *type)
+/**
+ * Parses a function type parameter list and return a list of declarations.
+ *
+ * @param last  point to the last element of the list
+ * @return the parameter list
+ */
+static declaration_t *parse_parameters(function_type_t *type, declaration_t **last)
 {
        declaration_t *declarations = NULL;
 
@@ -3763,7 +3788,7 @@ static declaration_t *parse_parameters(function_type_t *type)
                token_type_t la1_type = (token_type_t)look_ahead(1)->type;
                if (la1_type == ',' || la1_type == ')') {
                        type->kr_style_parameters = true;
-                       declarations = parse_identifier_list();
+                       declarations = parse_identifier_list(last);
                        goto parameters_finished;
                }
        }
@@ -3829,10 +3854,12 @@ parameters_finished:
        expect(')');
 
        restore_anchor_state(',', saved_comma_state);
+       *last = last_declaration;
        return declarations;
 
 end_error:
        restore_anchor_state(',', saved_comma_state);
+       *last = NULL;
        return NULL;
 }
 
@@ -3968,9 +3995,12 @@ static construct_type_t *parse_function_declarator(declaration_t *declaration)
                type = allocate_type_zero(TYPE_FUNCTION, HERE);
        }
 
-       declaration_t *parameters = parse_parameters(&type->function);
+       declaration_t *last;
+       declaration_t *parameters = parse_parameters(&type->function, &last);
        if (declaration != NULL) {
-               declaration->scope.declarations = parameters;
+               declaration->scope.declarations     = parameters;
+               declaration->scope.last_declaration = last;
+               declaration->scope.is_parameter     = true;
        }
 
        construct_function_type_t *construct_function_type =
@@ -4394,8 +4424,16 @@ static declaration_t *record_declaration(
        }
 
        assert(declaration != previous_declaration);
-       if (previous_declaration != NULL
-                       && previous_declaration->parent_scope == scope) {
+       if (previous_declaration != NULL &&
+           previous_declaration->parent_scope->is_parameter) {
+               errorf(&declaration->source_position,
+                       "declaration '%#T' redeclares the parameter '%#T' (declared %P)",
+                       orig_type, symbol, previous_declaration->type, symbol,
+                       &previous_declaration->source_position);
+               goto finish;
+       }
+       if (previous_declaration != NULL &&
+           previous_declaration->parent_scope == scope) {
                /* can happen for K&R style declarations */
                if (previous_declaration->type == NULL) {
                        previous_declaration->type = declaration->type;
@@ -4527,7 +4565,7 @@ warn_redundant_declaration:
                                 "no previous declaration for '%#T'", orig_type, symbol);
                }
        }
-
+finish:
        assert(declaration->parent_scope == NULL);
        assert(scope != NULL);
 
@@ -4764,8 +4802,7 @@ static void parse_kr_declaration_list(declaration_t *declaration)
 
        /* push function parameters */
        int       top        = environment_top();
-       scope_t  *last_scope = scope;
-       set_scope(&declaration->scope);
+       scope_push(&declaration->scope);
 
        declaration_t *parameter = declaration->scope.declarations;
        for ( ; parameter != NULL; parameter = parameter->next) {
@@ -4781,7 +4818,7 @@ static void parse_kr_declaration_list(declaration_t *declaration)
 
        /* pop function parameters */
        assert(scope == &declaration->scope);
-       set_scope(last_scope);
+       scope_pop();
        environment_pop_to(top);
 
        /* update function type */
@@ -5479,9 +5516,8 @@ static void parse_external_declaration(void)
        type = skip_typeref(declaration->type);
 
        /* push function parameters and switch scope */
-       int       top        = environment_top();
-       scope_t  *last_scope = scope;
-       set_scope(&declaration->scope);
+       int top = environment_top();
+       scope_push(&declaration->scope);
 
        declaration_t *parameter = declaration->scope.declarations;
        for( ; parameter != NULL; parameter = parameter->next) {
@@ -5536,7 +5572,7 @@ static void parse_external_declaration(void)
        }
 
        assert(scope == &declaration->scope);
-       set_scope(last_scope);
+       scope_pop();
        environment_pop_to(top);
 }
 
@@ -6124,6 +6160,12 @@ static expression_t *parse_reference(void)
        /* this declaration is used */
        declaration->used = true;
 
+       if (declaration->parent_scope != global_scope &&
+               declaration->parent_scope->depth < current_function->scope.depth) {
+               /* access of a variable from an outer function */
+               declaration->address_taken = true;
+       }
+
        /* check for deprecated functions */
        if (warning.deprecated_declarations &&
            declaration->modifiers & DM_DEPRECATED) {
@@ -9153,9 +9195,8 @@ static statement_t *parse_for(void)
 
        PUSH_PARENT(statement);
 
-       int      top        = environment_top();
-       scope_t *last_scope = scope;
-       set_scope(&statement->fors.scope);
+       int top = environment_top();
+       scope_push(&statement->fors.scope);
 
        expect('(');
        add_anchor_token(')');
@@ -9197,7 +9238,7 @@ static statement_t *parse_for(void)
        statement->fors.body = parse_loop_body(statement);
 
        assert(scope == &statement->fors.scope);
-       set_scope(last_scope);
+       scope_pop();
        environment_pop_to(top);
 
        POP_PARENT;
@@ -9207,7 +9248,7 @@ end_error:
        POP_PARENT;
        rem_anchor_token(')');
        assert(scope == &statement->fors.scope);
-       set_scope(last_scope);
+       scope_pop();
        environment_pop_to(top);
 
        return create_invalid_statement();
@@ -9763,10 +9804,9 @@ static statement_t *parse_compound_statement(bool inside_expression_statement)
        eat('{');
        add_anchor_token('}');
 
-       int      top        = environment_top();
-       int      top_local  = local_label_top();
-       scope_t *last_scope = scope;
-       set_scope(&statement->compound.scope);
+       int top       = environment_top();
+       int top_local = local_label_top();
+       scope_push(&statement->compound.scope);
 
        statement_t **anchor            = &statement->compound.statements;
        bool          only_decls_so_far = true;
@@ -9825,7 +9865,7 @@ static statement_t *parse_compound_statement(bool inside_expression_statement)
 end_error:
        rem_anchor_token('}');
        assert(scope == &statement->compound.scope);
-       set_scope(last_scope);
+       scope_pop();
        environment_pop_to(top);
        local_label_pop_to(top_local);
 
@@ -9989,15 +10029,16 @@ void start_parsing(void)
        global_scope = &unit->scope;
 
        assert(scope == NULL);
-       set_scope(&unit->scope);
+       scope_push(&unit->scope);
 
        initialize_builtin_types();
 }
 
 translation_unit_t *finish_parsing(void)
 {
+       /* do NOT use scope_pop() here, this will crash, will it by hand */
        assert(scope == &unit->scope);
-       scope          = NULL;
+       scope            = NULL;
        last_declaration = NULL;
 
        assert(global_scope == &unit->scope);