llvm-project/clang/test/CXX/dcl.dcl/dcl.attr/dcl.attr.fallthrough/p1.cpp

71 lines
2.4 KiB
C++

// RUN: %clang_cc1 -fsyntax-only -std=c++1z -verify %s
void f(int n) {
switch (n) {
case 0:
n += 1;
[[fallthrough]]; // ok
case 1:
if (n) {
[[fallthrough]]; // ok
} else {
return;
}
case 2:
for (int n = 0; n != 10; ++n)
[[fallthrough]]; // expected-error {{does not directly precede switch label}}
case 3:
while (true)
[[fallthrough]]; // expected-error {{does not directly precede switch label}}
case 4:
while (false)
[[fallthrough]]; // expected-error {{does not directly precede switch label}}
case 5:
do [[fallthrough]]; while (true); // expected-error {{does not directly precede switch label}}
case 6:
do [[fallthrough]]; while (false); // expected-error {{does not directly precede switch label}}
case 7:
switch (n) {
case 0:
// FIXME: This should be an error, even though the next thing we do is to
// fall through in an outer switch statement.
[[fallthrough]];
}
case 8:
[[fallthrough]]; // expected-error {{does not directly precede switch label}}
goto label;
label:
case 9:
n += 1;
case 10: // no warning, -Wimplicit-fallthrough is not enabled in this test, and does not need to
// be enabled for these diagnostics to be produced.
break;
}
}
[[fallthrough]] typedef int n; // expected-error {{'fallthrough' attribute cannot be applied to a declaration}}
typedef int [[fallthrough]] n; // expected-error {{'fallthrough' attribute cannot be applied to types}}
typedef int n [[fallthrough]]; // expected-error {{'fallthrough' attribute cannot be applied to a declaration}}
enum [[fallthrough]] E {}; // expected-error {{'fallthrough' attribute cannot be applied to a declaration}}
class [[fallthrough]] C {}; // expected-error {{'fallthrough' attribute cannot be applied to a declaration}}
[[fallthrough]] // expected-error {{'fallthrough' attribute cannot be applied to a declaration}}
void g() {
[[fallthrough]] int n; // expected-error {{'fallthrough' attribute cannot be applied to a declaration}}
[[fallthrough]] ++n; // expected-error-re {{{{^}}fallthrough attribute is only allowed on empty statements}}
switch (n) {
// FIXME: This should be an error.
[[fallthrough]];
return;
case 0:
[[fallthrough, fallthrough]]; // expected-error {{multiple times}}
case 1:
[[fallthrough(0)]]; // expected-error {{argument list}}
case 2:
break;
}
}