| // RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 -Wimplicit-fallthrough %s |
| |
| |
| int fallthrough(int n) { |
| switch (n / 10) { |
| if (n - 1) { |
| n = 100; |
| } else if (n - 2) { |
| n = 101; |
| } else if (n - 3) { |
| n = 102; |
| } |
| case -1: // no warning here, ignore fall-through from unreachable code |
| ; |
| case 0: {// expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert '[[clang::fallthrough]];' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}} |
| } |
| case 1: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert '[[clang::fallthrough]];' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}} |
| n += 100 ; |
| case 3: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert '[[clang::fallthrough]];' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}} |
| if (n > 0) |
| n += 200; |
| case 4: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert '[[clang::fallthrough]];' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}} |
| if (n < 0) |
| ; |
| case 5: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert '[[clang::fallthrough]];' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}} |
| switch (n) { |
| case 111: |
| break; |
| case 112: |
| break; |
| case 113: |
| break ; |
| } |
| case 6: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert '[[clang::fallthrough]];' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}} |
| n += 300; |
| case 66: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert 'break;' to avoid fall-through}} |
| case 67: |
| case 68: |
| break; |
| } |
| switch (n / 15) { |
| label_default: |
| default: |
| n += 333; |
| if (n % 10) |
| goto label_default; |
| break; |
| case 70: |
| n += 335; |
| break; |
| } |
| switch (n / 20) { |
| case 7: |
| n += 400; |
| [[clang::fallthrough]]; |
| case 9: // no warning here, intended fall-through marked with an attribute |
| n += 800; |
| [[clang::fallthrough]]; |
| default: { // no warning here, intended fall-through marked with an attribute |
| if (n % 2 == 0) { |
| return 1; |
| } else { |
| [[clang::fallthrough]]; |
| } |
| } |
| case 10: // no warning here, intended fall-through marked with an attribute |
| if (n % 3 == 0) { |
| n %= 3; |
| } else { |
| [[clang::fallthrough]]; |
| } |
| case 110: // expected-warning{{unannotated fall-through between switch labels}} but no fix-it hint as we have one fall-through annotation! |
| n += 800; |
| } |
| switch (n / 30) { |
| case 11: |
| case 12: // no warning here, intended fall-through, no statement between labels |
| n += 1600; |
| } |
| switch (n / 40) { |
| case 13: |
| if (n % 2 == 0) { |
| return 1; |
| } else { |
| return 2; |
| } |
| case 15: // no warning here, there's no fall-through |
| n += 3200; |
| } |
| switch (n / 50) { |
| case 17: { |
| if (n % 2 == 0) { |
| return 1; |
| } else { |
| return 2; |
| } |
| } |
| case 19: { // no warning here, there's no fall-through |
| n += 6400; |
| return 3; |
| } |
| case 21: { // no warning here, there's no fall-through |
| break; |
| } |
| case 23: // no warning here, there's no fall-through |
| n += 128000; |
| break; |
| case 25: // no warning here, there's no fall-through |
| break; |
| } |
| |
| return n; |
| } |
| |
| class ClassWithDtor { |
| public: |
| ~ClassWithDtor() {} |
| }; |
| |
| void fallthrough2(int n) { |
| switch (n) { |
| case 0: |
| { |
| ClassWithDtor temp; |
| break; |
| } |
| default: // no warning here, there's no fall-through |
| break; |
| } |
| } |
| |
| void fallthrough3(int n) { |
| switch (n) { |
| case 1: |
| do { |
| return; |
| } while (0); |
| case 2: |
| do { |
| ClassWithDtor temp; |
| return; |
| } while (0); |
| case 3: |
| break; |
| } |
| } |
| |
| #define MY_SWITCH(X, Y, Z, U, V) switch (X) { case Y: Z; case U: V; } |
| #define MY_SWITCH2(X, Y, Z) switch (X) { Y; Z; } |
| #define MY_CASE(X, Y) case X: Y |
| #define MY_CASE2(X, Y, U, V) case X: Y; case U: V |
| |
| int fallthrough_macro1(int n) { |
| MY_SWITCH(n, 13, n *= 2, 14, break) // expected-warning{{unannotated fall-through between switch labels}} |
| |
| switch (n + 1) { |
| MY_CASE(33, n += 2); |
| MY_CASE(44, break); // expected-warning{{unannotated fall-through between switch labels}} |
| MY_CASE(55, n += 3); |
| } |
| |
| switch (n + 3) { |
| MY_CASE(333, return 333); |
| MY_CASE2(444, n += 44, 4444, break); // expected-warning{{unannotated fall-through between switch labels}} |
| MY_CASE(555, n += 33); |
| } |
| |
| MY_SWITCH2(n + 4, MY_CASE(17, n *= 3), MY_CASE(19, break)) // expected-warning{{unannotated fall-through between switch labels}} |
| |
| MY_SWITCH2(n + 5, MY_CASE(21, break), MY_CASE2(23, n *= 7, 25, break)) // expected-warning{{unannotated fall-through between switch labels}} |
| |
| return n; |
| } |
| |
| void fallthrough_cfgblock_with_null_successor(int x) { |
| (x && "") ? (void)(0) : (void)(1); |
| switch (x) {} |
| } |
| |
| int fallthrough_position(int n) { |
| switch (n) { |
| n += 300; |
| [[clang::fallthrough]]; // expected-warning{{fallthrough annotation in unreachable code}} |
| case 221: |
| return 1; |
| [[clang::fallthrough]]; // expected-warning{{fallthrough annotation in unreachable code}} |
| case 222: |
| n += 400; |
| case 223: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert '[[clang::fallthrough]];' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}} |
| ; |
| } |
| |
| long p = static_cast<long>(n) * n; |
| switch (sizeof(p)) { |
| case 9: |
| n += static_cast<int>(p >> 32); |
| [[clang::fallthrough]]; // no warning here |
| case 5: |
| n += static_cast<int>(p); |
| [[clang::fallthrough]]; // no warning here |
| default: |
| n += 1; |
| break; |
| } |
| |
| return n; |
| } |
| |
| enum Enum { |
| Value1, Value2 |
| }; |
| |
| int fallthrough_covered_enums(Enum e) { |
| int n = 0; |
| switch (e) { |
| default: |
| n += 17; |
| [[clang::fallthrough]]; // no warning here, this shouldn't be treated as unreachable code |
| case Value1: |
| n += 19; |
| break; |
| case Value2: |
| n += 21; |
| break; |
| } |
| return n; |
| } |
| |
| // Fallthrough annotations in local classes used to generate "fallthrough |
| // annotation does not directly precede switch label" warning. |
| void fallthrough_in_local_class() { |
| class C { |
| void f(int x) { |
| switch (x) { |
| case 0: |
| x++; |
| [[clang::fallthrough]]; // no diagnostics |
| case 1: |
| x++; |
| default: // \ |
| expected-warning{{unannotated fall-through between switch labels}} \ |
| expected-note{{insert 'break;' to avoid fall-through}} |
| break; |
| } |
| } |
| }; |
| } |
| |
| // Fallthrough annotations in lambdas used to generate "fallthrough |
| // annotation does not directly precede switch label" warning. |
| void fallthrough_in_lambda() { |
| (void)[] { |
| int x = 0; |
| switch (x) { |
| case 0: |
| x++; |
| [[clang::fallthrough]]; // no diagnostics |
| case 1: |
| x++; |
| default: // \ |
| expected-warning{{unannotated fall-through between switch labels}} \ |
| expected-note{{insert 'break;' to avoid fall-through}} |
| break; |
| } |
| }; |
| } |
| |
| namespace PR18983 { |
| void fatal() __attribute__((noreturn)); |
| int num(); |
| void test() { |
| switch (num()) { |
| case 1: |
| fatal(); |
| // Don't issue a warning. |
| case 2: |
| break; |
| } |
| } |
| } |
| |
| int fallthrough_placement_error(int n) { |
| switch (n) { |
| [[clang::fallthrough]]; // expected-warning{{fallthrough annotation in unreachable code}} |
| n += 300; |
| case 221: |
| [[clang::fallthrough]]; // expected-error{{fallthrough annotation does not directly precede switch label}} |
| return 1; |
| case 222: |
| [[clang::fallthrough]]; // expected-error{{fallthrough annotation does not directly precede switch label}} |
| n += 400; |
| [[clang::fallthrough]]; |
| case 223: |
| [[clang::fallthrough]]; // expected-error{{fallthrough annotation does not directly precede switch label}} |
| } |
| return n; |
| } |
| |
| int fallthrough_targets(int n) { |
| [[clang::fallthrough]]; // expected-error{{fallthrough annotation is outside switch statement}} |
| |
| [[clang::fallthrough]] // expected-error{{fallthrough attribute is only allowed on empty statements}} |
| switch (n) { |
| case 121: |
| n += 400; |
| [[clang::fallthrough]]; // no warning here, correct target |
| case 123: |
| [[clang::fallthrough]] // expected-error{{fallthrough attribute is only allowed on empty statements}} |
| n += 800; |
| break; |
| [[clang::fallthrough]] // expected-error{{fallthrough attribute is only allowed on empty statements}} expected-note{{did you forget ';'?}} |
| case 125: |
| n += 1600; |
| } |
| return n; |
| } |
| |
| int fallthrough_alt_spelling(int n) { |
| switch (n) { |
| case 0: |
| n++; |
| [[clang::fallthrough]]; |
| case 1: |
| n++; |
| [[clang::__fallthrough__]]; |
| case 2: |
| n++; |
| break; |
| } |
| return n; |
| } |
| |
| int fallthrough_attribute_spelling(int n) { |
| switch (n) { |
| case 0: |
| n++; |
| __attribute__((fallthrough)); |
| case 1: |
| n++; |
| break; |
| } |
| return n; |
| } |