1 // RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 -Wimplicit-fallthrough -DCOMMAND_LINE_FALLTHROUGH=[[clang::fallthrough]] %s 2 3 int fallthrough_compatibility_macro_from_command_line(int n) { 4 switch (n) { 5 case 0: 6 n = n * 10; 7 case 1: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert 'COMMAND_LINE_FALLTHROUGH;' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}} 8 ; 9 } 10 return n; 11 } 12 13 #ifdef __clang__ 14 #if __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough") 15 #define COMPATIBILITY_FALLTHROUGH [ [ /* test */ clang /* test */ \ 16 :: fallthrough ] ] // testing whitespace and comments in macro definition 17 #endif 18 #endif 19 20 #ifndef COMPATIBILITY_FALLTHROUGH 21 #define COMPATIBILITY_FALLTHROUGH do { } while (0) 22 #endif 23 24 int fallthrough_compatibility_macro_from_source(int n) { 25 switch (n) { 26 case 0: 27 n = n * 20; 28 case 1: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert 'COMPATIBILITY_FALLTHROUGH;' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}} 29 ; 30 } 31 return n; 32 } 33 34 // Deeper macro substitution 35 #define M1 [[clang::fallthrough]] 36 #ifdef __clang__ 37 #define M2 M1 38 #else 39 #define M2 40 #endif 41 42 #define WRONG_MACRO1 clang::fallthrough 43 #define WRONG_MACRO2 [[clang::fallthrough] 44 #define WRONG_MACRO3 [[clang::fall through]] 45 #define WRONG_MACRO4 [[clang::fallthrough]]] 46 47 int fallthrough_compatibility_macro_in_macro(int n) { 48 switch (n) { 49 case 0: 50 n = n * 20; 51 case 1: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert 'M1;' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}} 52 // there was an idea that this ^ should be M2 53 ; 54 } 55 return n; 56 } 57 58 #undef M1 59 #undef M2 60 #undef COMPATIBILITY_FALLTHROUGH 61 #undef COMMAND_LINE_FALLTHROUGH 62 63 int fallthrough_compatibility_macro_undefined(int n) { 64 switch (n) { 65 case 0: 66 n = n * 20; 67 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}} 68 ; 69 } 70 #define TOO_LATE [[clang::fallthrough]] 71 return n; 72 } 73 #undef TOO_LATE 74 75 #define MACRO_WITH_HISTORY 11111111 76 #undef MACRO_WITH_HISTORY 77 #define MACRO_WITH_HISTORY [[clang::fallthrough]] 78 #undef MACRO_WITH_HISTORY 79 #define MACRO_WITH_HISTORY 2222222 80 81 int fallthrough_compatibility_macro_history(int n) { 82 switch (n) { 83 case 0: 84 n = n * 20; 85 #undef MACRO_WITH_HISTORY 86 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}} 87 ; 88 #define MACRO_WITH_HISTORY [[clang::fallthrough]] 89 } 90 return n; 91 } 92 93 #undef MACRO_WITH_HISTORY 94 #define MACRO_WITH_HISTORY 11111111 95 #undef MACRO_WITH_HISTORY 96 #define MACRO_WITH_HISTORY [[clang::fallthrough]] 97 #undef MACRO_WITH_HISTORY 98 #define MACRO_WITH_HISTORY 2222222 99 #undef MACRO_WITH_HISTORY 100 101 int fallthrough_compatibility_macro_history2(int n) { 102 switch (n) { 103 case 0: 104 n = n * 20; 105 #define MACRO_WITH_HISTORY [[clang::fallthrough]] 106 case 1: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert 'MACRO_WITH_HISTORY;' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}} 107 ; 108 #undef MACRO_WITH_HISTORY 109 #define MACRO_WITH_HISTORY 3333333 110 #undef MACRO_WITH_HISTORY 111 #define MACRO_WITH_HISTORY 4444444 112 #undef MACRO_WITH_HISTORY 113 #define MACRO_WITH_HISTORY 5555555 114 } 115 return n; 116 } 117 118 template<const int N> 119 int fallthrough_compatibility_macro_history_template(int n) { 120 switch (N * n) { 121 case 0: 122 n = n * 20; 123 #define MACRO_WITH_HISTORY2 [[clang::fallthrough]] 124 case 1: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert 'MACRO_WITH_HISTORY2;' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}} 125 ; 126 #undef MACRO_WITH_HISTORY2 127 #define MACRO_WITH_HISTORY2 3333333 128 } 129 return n; 130 } 131 132 #undef MACRO_WITH_HISTORY2 133 #define MACRO_WITH_HISTORY2 4444444 134 #undef MACRO_WITH_HISTORY2 135 #define MACRO_WITH_HISTORY2 5555555 136 137 void f() { 138 fallthrough_compatibility_macro_history_template<1>(0); // expected-note{{in instantiation of function template specialization 'fallthrough_compatibility_macro_history_template<1>' requested here}} 139 } 140