X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=parser.c;h=7d9b3347762a90999398158718d0e5bf4fbc0460;hb=65dfc72272eeb6beba7d3a53ebd9a46488000c81;hp=d34696a735cd30a95dd757150edb2991c5fd137a;hpb=64bf64a7a86bc49d31bb0d7a1e9f90f94cf259bb;p=cparser

diff --git a/parser.c b/parser.c
index d34696a..7d9b334 100644
--- a/parser.c
+++ b/parser.c
@@ -49,6 +49,9 @@ static context_t          *context           = NULL;
 static declaration_t      *last_declaration  = NULL;
 static declaration_t      *current_function  = NULL;
 static switch_statement_t *current_switch    = NULL;
+static statement_t        *current_loop      = NULL;
+static goto_statement_t   *goto_first        = NULL;
+static goto_statement_t   *goto_last         = NULL;
 static struct obstack  temp_obst;
 
 /** The current source position. */
@@ -2685,6 +2688,31 @@ static void parse_kr_declaration_list(declaration_t *declaration)
 	declaration->type = type;
 }
 
+/**
+ * Check if all labels are defined in the current function.
+ */
+static void check_for_missing_labels(void)
+{
+	bool first_err = true;
+	for (const goto_statement_t *goto_statement = goto_first;
+	     goto_statement != NULL;
+	     goto_statement = goto_statement->next) {
+		 const declaration_t *label = goto_statement->label;
+
+		 if (label->source_position.input_name == NULL) {
+			 if (first_err) {
+				 first_err = false;
+				 diagnosticf("%s: In function '%Y':\n",
+					 current_function->source_position.input_name,
+					 current_function->symbol);
+			 }
+			 errorf(goto_statement->statement.source_position,
+				 "label '%Y' used but not defined", label->symbol);
+		 }
+	}
+	goto_first = goto_last = NULL;
+}
+
 static void parse_external_declaration(void)
 {
 	/* function-definitions and declarations both start with declaration
@@ -2778,6 +2806,7 @@ static void parse_external_declaration(void)
 		current_function                    = declaration;
 
 		declaration->init.statement = parse_compound_statement();
+		check_for_missing_labels();
 
 		assert(current_function == declaration);
 		current_function = old_current_function;
@@ -4849,23 +4878,44 @@ static statement_t *parse_case_statement(void)
 
 	expect(':');
 
-	if (current_switch != NULL) {
-		/* link all cases into the switch statement */
-		if (current_switch->last_case == NULL) {
-			current_switch->first_case =
-			current_switch->last_case  = &statement->case_label;
+	if (! is_constant_expression(statement->case_label.expression)) {
+		errorf(statement->base.source_position,
+			"case label does not reduce to an integer constant");
+	} else {
+		/* TODO: check if the case label is already known */
+		if (current_switch != NULL) {
+			/* link all cases into the switch statement */
+			if (current_switch->last_case == NULL) {
+				current_switch->first_case =
+				current_switch->last_case  = &statement->case_label;
+			} else {
+				current_switch->last_case->next = &statement->case_label;
+			}
 		} else {
-			current_switch->last_case->next = &statement->case_label;
+			errorf(statement->base.source_position,
+				"case label not within a switch statement");
 		}
-	} else {
-		errorf(statement->base.source_position,
-			"case label not within a switch statement");
 	}
 	statement->case_label.label_statement = parse_statement();
 
 	return statement;
 }
 
+/**
+ * Finds an existing default label of a switch statement.
+ */
+static case_label_statement_t *
+find_default_label(const switch_statement_t *statement)
+{
+	for (case_label_statement_t *label = statement->first_case;
+	     label != NULL;
+		 label = label->next) {
+		if (label->expression == NULL)
+			return label;
+	}
+	return NULL;
+}
+
 /**
  * Parse a default statement.
  */
@@ -4878,6 +4928,25 @@ static statement_t *parse_default_statement(void)
 	statement->base.source_position = token.source_position;
 
 	expect(':');
+	if (current_switch != NULL) {
+		const case_label_statement_t *def_label = find_default_label(current_switch);
+		if (def_label != NULL) {
+			errorf(HERE, "multiple default labels in one switch");
+			errorf(def_label->statement.source_position,
+				"this is the first default label");
+		} else {
+			/* link all cases into the switch statement */
+			if (current_switch->last_case == NULL) {
+				current_switch->first_case =
+					current_switch->last_case  = &statement->case_label;
+			} else {
+				current_switch->last_case->next = &statement->case_label;
+			}
+		}
+	} else {
+		errorf(statement->base.source_position,
+			"'default' label not within a switch statement");
+	}
 	statement->label.label_statement = parse_statement();
 
 	return statement;
@@ -4989,13 +5058,22 @@ static statement_t *parse_switch(void)
 	expect(')');
 
 	switch_statement_t *rem = current_switch;
-	current_switch  = &statement;
+	current_switch  = statement;
 	statement->body = parse_statement();
 	current_switch  = rem;
 
 	return (statement_t*) statement;
 }
 
+static statement_t *parse_loop_body(statement_t *const loop)
+{
+	statement_t *const rem = current_loop;
+	current_loop = loop;
+	statement_t *const body = parse_statement();
+	current_loop = rem;
+	return body;
+}
+
 /**
  * Parse a while statement.
  */
@@ -5010,7 +5088,8 @@ static statement_t *parse_while(void)
 	expect('(');
 	statement->condition = parse_expression();
 	expect(')');
-	statement->body = parse_statement();
+
+	statement->body = parse_loop_body((statement_t*)statement);
 
 	return (statement_t*) statement;
 }
@@ -5026,7 +5105,7 @@ static statement_t *parse_do(void)
 	statement->statement.kind            = STATEMENT_DO_WHILE;
 	statement->statement.source_position = token.source_position;
 
-	statement->body = parse_statement();
+	statement->body = parse_loop_body((statement_t*)statement);
 	expect(T_while);
 	expect('(');
 	statement->condition = parse_expression();
@@ -5072,7 +5151,7 @@ static statement_t *parse_for(void)
 		statement->step = parse_expression();
 	}
 	expect(')');
-	statement->body = parse_statement();
+	statement->body = parse_loop_body((statement_t*)statement);
 
 	assert(context == &statement->context);
 	set_context(last_context);
@@ -5105,6 +5184,13 @@ static statement_t *parse_goto(void)
 
 	statement->label = label;
 
+	/* remember the goto's in a list for later checking */
+	if (goto_last == NULL) {
+		goto_first = goto_last = statement;
+	} else {
+		goto_last->next = statement;
+	}
+
 	expect(';');
 
 	return (statement_t*) statement;
@@ -5115,14 +5201,20 @@ static statement_t *parse_goto(void)
  */
 static statement_t *parse_continue(void)
 {
+	statement_base_t *statement;
+	if (current_loop == NULL) {
+		errorf(HERE, "continue statement not within loop");
+		statement = NULL;
+	} else {
+		statement                  = allocate_ast_zero(sizeof(statement[0]));
+		statement->kind            = STATEMENT_CONTINUE;
+		statement->source_position = token.source_position;
+	}
+
 	eat(T_continue);
 	expect(';');
 
-	statement_t *statement          = allocate_ast_zero(sizeof(statement[0]));
-	statement->kind                 = STATEMENT_CONTINUE;
-	statement->base.source_position = token.source_position;
-
-	return statement;
+	return (statement_t*)statement;
 }
 
 /**
@@ -5130,14 +5222,20 @@ static statement_t *parse_continue(void)
  */
 static statement_t *parse_break(void)
 {
+	statement_base_t *statement;
+	if (current_switch == NULL && current_loop == NULL) {
+		errorf(HERE, "break statement not within loop or switch");
+		statement = NULL;
+	} else {
+		statement                  = allocate_ast_zero(sizeof(statement[0]));
+		statement->kind            = STATEMENT_BREAK;
+		statement->source_position = token.source_position;
+	}
+
 	eat(T_break);
 	expect(';');
 
-	statement_t *statement          = allocate_ast_zero(sizeof(statement[0]));
-	statement->kind                 = STATEMENT_BREAK;
-	statement->base.source_position = token.source_position;
-
-	return statement;
+	return (statement_t*)statement;
 }
 
 /**