71 lines · cpp
1// RUN: %clang_cc1 -fsyntax-only -std=c++1z -verify %s2 3void f(int n) {4 switch (n) {5 case 0:6 n += 1;7 [[fallthrough]]; // ok8 case 1:9 if (n) {10 [[fallthrough]]; // ok11 } else {12 return;13 }14 case 2:15 for (int n = 0; n != 10; ++n)16 [[fallthrough]]; // expected-error {{does not directly precede switch label}}17 case 3:18 while (true)19 [[fallthrough]]; // expected-error {{does not directly precede switch label}}20 case 4:21 while (false)22 [[fallthrough]]; // expected-error {{does not directly precede switch label}}23 case 5:24 do [[fallthrough]]; while (true); // expected-error {{does not directly precede switch label}}25 case 6:26 do [[fallthrough]]; while (false); // expected-error {{does not directly precede switch label}}27 case 7:28 switch (n) {29 case 0:30 // FIXME: This should be an error, even though the next thing we do is to31 // fall through in an outer switch statement.32 [[fallthrough]];33 }34 case 8:35 [[fallthrough]]; // expected-error {{does not directly precede switch label}}36 goto label;37 label:38 case 9:39 n += 1;40 case 10: // no warning, -Wimplicit-fallthrough is not enabled in this test, and does not need to41 // be enabled for these diagnostics to be produced.42 break;43 }44}45 46[[fallthrough]] typedef int n; // expected-error {{'fallthrough' attribute cannot be applied to a declaration}}47typedef int [[fallthrough]] n; // expected-error {{'fallthrough' attribute cannot be applied to types}}48typedef int n [[fallthrough]]; // expected-error {{'fallthrough' attribute cannot be applied to a declaration}}49 50enum [[fallthrough]] E {}; // expected-error {{'fallthrough' attribute cannot be applied to a declaration}}51class [[fallthrough]] C {}; // expected-error {{'fallthrough' attribute cannot be applied to a declaration}}52 53[[fallthrough]] // expected-error {{'fallthrough' attribute cannot be applied to a declaration}}54void g() {55 [[fallthrough]] int n; // expected-error {{'fallthrough' attribute cannot be applied to a declaration}}56 [[fallthrough]] ++n; // expected-error {{'fallthrough' attribute only applies to empty statements}}57 58 switch (n) {59 // FIXME: This should be an error.60 [[fallthrough]];61 return;62 63 case 0:64 [[fallthrough, fallthrough]]; // ok65 case 1:66 [[fallthrough(0)]]; // expected-error {{argument list}}67 case 2:68 break;69 }70}71