1 // RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 -Wimplicit-fallthrough -DCLANG_PREFIX -DCOMMAND_LINE_FALLTHROUGH=[[clang::fallthrough]] -DUNCHOSEN=[[fallthrough]] %s
2 // RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 -Wimplicit-fallthrough -DCOMMAND_LINE_FALLTHROUGH=[[fallthrough]] %s
3 // RUN: %clang_cc1 -fsyntax-only -verify -std=c++1z -Wimplicit-fallthrough -DCLANG_PREFIX -DCOMMAND_LINE_FALLTHROUGH=[[clang::fallthrough]] %s
4 // RUN: %clang_cc1 -fsyntax-only -verify -std=c++1z -Wimplicit-fallthrough -DCOMMAND_LINE_FALLTHROUGH=[[clang::fallthrough]] %s
5 // RUN: %clang_cc1 -fsyntax-only -verify -std=c++1z -Wimplicit-fallthrough -DCOMMAND_LINE_FALLTHROUGH=[[fallthrough]] -DUNCHOSEN=[[clang::fallthrough]] %s
6 
fallthrough_compatibility_macro_from_command_line(int n)7 int fallthrough_compatibility_macro_from_command_line(int n) {
8   switch (n) {
9     case 0:
10       n = n * 10;
11     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}}
12       ;
13   }
14   return n;
15 }
16 
17 #ifdef CLANG_PREFIX
18 #define COMPATIBILITY_FALLTHROUGH   [ [ /* test */  clang /* test */ \
19     ::  fallthrough  ]  ]    // testing whitespace and comments in macro definition
20 #else
21 #define COMPATIBILITY_FALLTHROUGH   [ [ /* test */  /* test */ \
22     fallthrough  ]  ]    // testing whitespace and comments in macro definition
23 #endif
24 
fallthrough_compatibility_macro_from_source(int n)25 int fallthrough_compatibility_macro_from_source(int n) {
26   switch (n) {
27     case 0:
28       n = n * 20;
29     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}}
30       ;
31   }
32   return n;
33 }
34 
35 // Deeper macro substitution
36 #ifdef CLANG_PREFIX
37 #define M1 [[clang::fallthrough]]
38 #else
39 #define M1 [[fallthrough]]
40 #endif
41 #ifdef __clang__
42 #define M2 M1
43 #else
44 #define M2
45 #endif
46 
47 #define WRONG_MACRO1 clang::fallthrough
48 #define WRONG_MACRO2 [[clang::fallthrough]
49 #define WRONG_MACRO3 [[clang::fall through]]
50 #define WRONG_MACRO4 [[clang::fallthrough]]]
51 
fallthrough_compatibility_macro_in_macro(int n)52 int fallthrough_compatibility_macro_in_macro(int n) {
53   switch (n) {
54     case 0:
55       n = n * 20;
56     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}}
57                                                                           // there was an idea that this ^ should be M2
58       ;
59   }
60   return n;
61 }
62 
63 #undef M1
64 #undef M2
65 #undef COMPATIBILITY_FALLTHROUGH
66 #undef COMMAND_LINE_FALLTHROUGH
67 #undef UNCHOSEN
68 
fallthrough_compatibility_macro_undefined(int n)69 int fallthrough_compatibility_macro_undefined(int n) {
70   switch (n) {
71     case 0:
72       n = n * 20;
73 #if __cplusplus <= 201402L
74     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}}
75 #else
76     case 1: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert '[[fallthrough]];' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}}
77 #endif
78       ;
79   }
80 #define TOO_LATE [[clang::fallthrough]]
81   return n;
82 }
83 #undef TOO_LATE
84 
85 #define MACRO_WITH_HISTORY 11111111
86 #undef MACRO_WITH_HISTORY
87 #define MACRO_WITH_HISTORY [[clang::fallthrough]]
88 #undef MACRO_WITH_HISTORY
89 #define MACRO_WITH_HISTORY 2222222
90 
fallthrough_compatibility_macro_history(int n)91 int fallthrough_compatibility_macro_history(int n) {
92   switch (n) {
93     case 0:
94       n = n * 20;
95 #undef MACRO_WITH_HISTORY
96 #if __cplusplus <= 201402L
97     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}}
98 #else
99     case 1: // expected-warning{{unannotated fall-through between switch labels}} expected-note{{insert '[[fallthrough]];' to silence this warning}} expected-note{{insert 'break;' to avoid fall-through}}
100 #endif
101       ;
102 #define MACRO_WITH_HISTORY [[clang::fallthrough]]
103   }
104   return n;
105 }
106 
107 #undef MACRO_WITH_HISTORY
108 #define MACRO_WITH_HISTORY 11111111
109 #undef MACRO_WITH_HISTORY
110 #define MACRO_WITH_HISTORY [[clang::fallthrough]]
111 #undef MACRO_WITH_HISTORY
112 #define MACRO_WITH_HISTORY 2222222
113 #undef MACRO_WITH_HISTORY
114 
fallthrough_compatibility_macro_history2(int n)115 int fallthrough_compatibility_macro_history2(int n) {
116   switch (n) {
117     case 0:
118       n = n * 20;
119 #define MACRO_WITH_HISTORY [[clang::fallthrough]]
120     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}}
121       ;
122 #undef MACRO_WITH_HISTORY
123 #define MACRO_WITH_HISTORY 3333333
124 #undef MACRO_WITH_HISTORY
125 #define MACRO_WITH_HISTORY 4444444
126 #undef MACRO_WITH_HISTORY
127 #define MACRO_WITH_HISTORY 5555555
128   }
129   return n;
130 }
131 
132 template<const int N>
fallthrough_compatibility_macro_history_template(int n)133 int fallthrough_compatibility_macro_history_template(int n) {
134   switch (N * n) {
135     case 0:
136       n = n * 20;
137 #define MACRO_WITH_HISTORY2 [[clang::fallthrough]]
138     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}}
139       ;
140 #undef MACRO_WITH_HISTORY2
141 #define MACRO_WITH_HISTORY2 3333333
142   }
143   return n;
144 }
145 
146 #undef MACRO_WITH_HISTORY2
147 #define MACRO_WITH_HISTORY2 4444444
148 #undef MACRO_WITH_HISTORY2
149 #define MACRO_WITH_HISTORY2 5555555
150 
f()151 void f() {
152   fallthrough_compatibility_macro_history_template<1>(0); // expected-note{{in instantiation of function template specialization 'fallthrough_compatibility_macro_history_template<1>' requested here}}
153 }
154