llvm-project

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// RUN: %clang_cc1 -fsyntax-only -verify -Wdangling-else %s
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void f(int a, int b, int c, int d, int e) {
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  // should warn
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  { if (a) if (b) d++; else e++; } // expected-warning {{add explicit braces to avoid dangling else}}
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  { if (a) while (b) if (c) d++; else e++; } // expected-warning {{add explicit braces to avoid dangling else}}
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  { if (a) switch (b) if (c) d++; else e++; } // expected-warning {{add explicit braces to avoid dangling else}}
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  { if (a) for (;;) if (c) d++; else e++; } // expected-warning {{add explicit braces to avoid dangling else}}
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  { if (a) if (b) if (d) d++; else e++; else d--; } // expected-warning {{add explicit braces to avoid dangling else}}
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  if (a)
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    if (b) {
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      d++;
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    } else e++; // expected-warning {{add explicit braces to avoid dangling else}}
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  // shouldn't
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  { if (a) if (b) d++; }
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  { if (a) if (b) if (c) d++; }
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  { if (a) if (b) d++; else e++; else d--; }
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  { if (a) if (b) if (d) d++; else e++; else d--; else e--; }
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  { if (a) do if (b) d++; else e++; while (c); }
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  if (a) {
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    if (b) d++;
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    else e++;
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  }
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  if (a) {
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    if (b) d++;
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  } else e++;
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}
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// Somewhat more elaborate case that shouldn't warn.
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class A {
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 public:
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  void operator<<(const char* s) {}
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};
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void HandleDisabledThing() {}
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A GetThing() { return A(); }
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#define FOO(X) \
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   switch (0) default: \
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     if (!(X)) \
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       HandleDisabledThing(); \
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     else \
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       GetThing()
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void f(bool cond) {
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  int x = 0;
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  if (cond)
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    FOO(x) << "hello"; // no warning
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}
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