diff --git a/src/Sema.zig b/src/Sema.zig index c9dacd1185..559f5d2731 100644 --- a/src/Sema.zig +++ b/src/Sema.zig @@ -9846,11 +9846,19 @@ fn analyzeAs( const mod = sema.mod; const operand = try sema.resolveInst(zir_operand); if (zir_dest_type == .var_args_param_type) return operand; - const dest_ty = sema.resolveType(block, src, zir_dest_type) catch |err| switch (err) { + const operand_air_inst = sema.resolveInst(zir_dest_type) catch |err| switch (err) { error.GenericPoison => return operand, else => |e| return e, }; - if (dest_ty.zigTypeTag(mod) == .NoReturn) { + if (operand_air_inst == .var_args_param_type) return operand; + const dest_ty = sema.analyzeAsType(block, src, operand_air_inst) catch |err| switch (err) { + error.GenericPoison => return operand, + else => |e| return e, + }; + const dest_ty_tag = dest_ty.zigTypeTagOrPoison(mod) catch |err| switch (err) { + error.GenericPoison => return operand, + }; + if (dest_ty_tag == .NoReturn) { return sema.fail(block, src, "cannot cast to noreturn", .{}); } const is_ret = if (Zir.refToIndex(zir_dest_type)) |ptr_index| diff --git a/test/behavior/var_args.zig b/test/behavior/var_args.zig index 134c302160..a2a00506f7 100644 --- a/test/behavior/var_args.zig +++ b/test/behavior/var_args.zig @@ -150,6 +150,15 @@ test "simple variadic function" { try std.testing.expectEqual(@as(c_int, 0), S.add(0)); try std.testing.expectEqual(@as(c_int, 1), S.add(1, @as(c_int, 1))); try std.testing.expectEqual(@as(c_int, 3), S.add(2, @as(c_int, 1), @as(c_int, 2))); + + { + // Test type coercion of a var args argument. + // Originally reported at https://github.com/ziglang/zig/issues/16197 + var runtime: bool = true; + var a: i32 = 1; + var b: i32 = 2; + try expect(1 == S.add(1, if (runtime) a else b)); + } } test "variadic functions" {