harec

commit fe4556d224d5b26a65843dcc9fe1cd9ac98785a1
parent 6c11668244aa2a3ce4288c24c626ca2225df0156
Author: Sebastian <sebastian@sebsite.pw>
Date:   Wed, 11 Jan 2023 18:25:51 -0500

check: fix type reduction when yielding without value

Previously, using `yield` without a value didn't correctly add a `void`
expression to the list of yields for a scope. So, for instance, code
like this would incorrectly compile:

	let x: int = {
		if (true) yield 0;
		yield;
	};

If the above `yield` was changed to a `yield void` this would correctly
not compile. This has been fixed, by adding a `void` value to a yield
without a value during check.

Signed-off-by: Sebastian <sebastian@sebsite.pw>

Diffstat:
M
src/check.c
 | 
29
++++++++++++++++++-----------
M
tests/30-reduction.c
 | 
5
+++++

2 files changed, 23 insertions(+), 11 deletions(-)
diff --git a/src/check.c b/src/check.c
@@ -1878,22 +1878,29 @@ check_expr_control(struct context *ctx,
 	}
 	expr->control.scope = scope;
 
+	if (expr->type != EXPR_YIELD) {
+		return;
+	}
+
+	expr->control.value = xcalloc(1, sizeof(struct expression));
 	if (aexpr->control.value) {
-		expr->control.value = xcalloc(1, sizeof(struct expression));
 		check_expression(ctx, aexpr->control.value,
 			expr->control.value, scope->hint);
+	} else {
+		expr->control.value->type = EXPR_CONSTANT;
+		expr->control.value->result = &builtin_type_void;
+	}
 
-		struct type_tagged_union *result =
-			xcalloc(1, sizeof(struct type_tagged_union));
-		result->type = expr->control.value->result;
-		result->next = scope->results;
-		scope->results = result;
+	struct type_tagged_union *result =
+		xcalloc(1, sizeof(struct type_tagged_union));
+	result->type = expr->control.value->result;
+	result->next = scope->results;
+	scope->results = result;
 
-		struct yield *yield = xcalloc(1, sizeof(struct yield));
-		yield->expression = &expr->control.value;
-		yield->next = scope->yields;
-		scope->yields = yield;
-	}
+	struct yield *yield = xcalloc(1, sizeof(struct yield));
+	yield->expression = &expr->control.value;
+	yield->next = scope->yields;
+	scope->yields = yield;
 }
 
 static void
diff --git a/tests/30-reduction.c b/tests/30-reduction.c
@@ -128,6 +128,11 @@ int main(void) {
 		"if (true) null: *int "
 		"else if (true) null: const nullable *int "
 		"else null: nullable *int");
+	test(&ctx, "(int | void)",
+		"{ "
+		"if (true) yield; "
+		"yield 0; "
+		"}");
 
 	test(&ctx, "",
 		"if (true) null "