- Passing a compile time type implicitly converted to a typeid would crash instead of producing an error. #2568

lib/std/collections/list.c3

@@ -532,7 +532,8 @@ fn bool List.remove_first_item(&self, Type value) @if(ELEMENT_IS_EQUATABLE)
 fn usz List.remove_item(&self, Type value) @if(ELEMENT_IS_EQUATABLE)
 {
 	usz old_size = self.size;
-	defer {
+	defer
+	{
 		if (old_size != self.size) self._update_size_change(old_size, self.size);
 	}
 	return list_common::list_remove_item(self, value);

releasenotes.md

@@ -16,6 +16,7 @@
 - Fix fmod `a %= 0f`.
 - Regression vector ABI: initializing a struct containing a NPOT vector with a constant value would crash LLVM. #2559
 - Error message with hashmap shows "mangled" name instead of original #2562.
+- Passing a compile time type implicitly converted to a typeid would crash instead of producing an error. #2568
 
 ### Stdlib changes
 

src/compiler/compiler_internal.h

@@ -4183,6 +4183,7 @@ INLINE void expr_rewrite_const_slice(Expr *expr, Type *type, ConstInitializer *i
 
 INLINE void expr_rewrite_const_typeid(Expr *expr, Type *type)
 {
+	ASSERT(type->type_kind != TYPE_UNTYPED_LIST);
 	expr->expr_kind = EXPR_CONST;
 	expr->const_expr.const_kind = CONST_TYPEID;
 	expr->const_expr.typeid = type->canonical;

src/compiler/sema_expr.c

@@ -6103,11 +6103,7 @@ static inline bool sema_expr_analyse_access(SemaContext *context, Expr *expr, bo
 				case CT_TYPES:
 					RETURN_SEMA_ERROR(parent, "You cannot take the typeid of a compile time type.");
 				default:
-					expr->type = type_typeid;
-					expr->expr_kind = EXPR_CONST;
-					expr->const_expr.const_kind = CONST_TYPEID;
-					expr->const_expr.typeid = parent->type_expr->type->canonical;
-					expr->resolve_status = RESOLVE_DONE;
+					expr_rewrite_const_typeid(expr, parent->type_expr->type->canonical);
 					return true;
 			}
 			UNREACHABLE
@@ -11737,8 +11733,15 @@ static inline bool sema_cast_rvalue(SemaContext *context, Expr *expr, bool mutat
 			if (mutate) sema_expr_flatten_const_ident(expr->access_resolved_expr.parent);
 			return true;
 		case EXPR_TYPEINFO:
-			expr_rewrite_const_typeid(expr, expr->type_expr->type);
-			return true;
+			switch (expr->type_expr->type->type_kind)
+			{
+				case CT_TYPES:
+					RETURN_SEMA_ERROR(expr, "You cannot take the typeid of a compile time type.");
+				default:
+					expr_rewrite_const_typeid(expr, expr->type_expr->type);
+					return true;
+			}
+			UNREACHABLE
 		case EXPR_CT_IDENT:
 			if (mutate && !sema_cast_ct_ident_rvalue(context, expr)) return false;
 			break;

test/test_suite/compile_time/typeid_implicit_ct.c3

@@ -0,0 +1,11 @@
+module test;
+import std;
+macro test(x)
+{
+	var $Type = $typeof(x);
+}
+fn int main()
+{
+	test($typeof({})); // #error: You cannot take the typeid of a compile time type
+	return 0;
+}