fix wrong type of case statements

§6.8.4.2:3 The expression of each case label shall be an integer
           constant expression
§6.8.4.2:5 The constant expression in each case label is converted to the
           promoted type of the controlling expression.

diff --git a/parser.c b/parser.c
index 23d6405..8986376 100644 (file)
--- a/parser.c
+++ b/parser.c
@@ -9103,7 +9103,22 @@ static statement_t *parse_case_statement(void)
 
        eat(T_case);
 
-       expression_t *const expression   = parse_expression();
+       expression_t *expression = parse_expression();
+       type_t *expression_type = expression->base.type;
+       type_t *skipped         = skip_typeref(expression_type);
+       if (!is_type_integer(skipped) && is_type_valid(skipped)) {
+               errorf(pos, "case expression '%E' must have integer type but has type '%T'",
+                      expression, expression_type);
+       }
+
+       type_t *type = expression_type;
+       if (current_switch != NULL) {
+               type_t *switch_type = current_switch->expression->base.type;
+               if (is_type_valid(switch_type)) {
+                       expression = create_implicit_cast(expression, switch_type);
+               }
+       }
+
        statement->case_label.expression = expression;
        expression_classification_t const expr_class = is_constant_expression(expression);
        if (expr_class != EXPR_CLASS_CONSTANT) {
@@ -9119,7 +9134,15 @@ static statement_t *parse_case_statement(void)
 
        if (GNU_MODE) {
                if (next_if(T_DOTDOTDOT)) {
-                       expression_t *const end_range   = parse_expression();
+                       expression_t *end_range = parse_expression();
+                       expression_type = expression->base.type;
+                       skipped         = skip_typeref(expression_type);
+                       if (!is_type_integer(skipped) && is_type_valid(skipped)) {
+                               errorf(pos, "case expression '%E' must have integer type but has type '%T'",
+                                          expression, expression_type);
+                       }
+
+                       end_range = create_implicit_cast(end_range, type);
                        statement->case_label.end_range = end_range;
                        expression_classification_t const end_class = is_constant_expression(end_range);
                        if (end_class != EXPR_CLASS_CONSTANT) {