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What is equivalent of GCC __attribute__ ((noreturn)) attribution in C#? To suppress warning about no return statement in a method on bad execution flow. My code will throw an error by calling error thrower function. I am using Mono included in Unity3D 4.0.

eonil
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  • this might help (?) Maybe harder with mono... http://msdn.microsoft.com/en-us/library/441722ys%28v=vs.100%29.aspx and also http://stackoverflow.com/questions/942238/list-of-pragma-warning-disable-codes-and-what-they-mean – Raphaël Althaus Jan 26 '13 at 22:23
  • Can you not just `throw` ? Or just out a throw underneath the method that already throws? – Marc Gravell Jan 26 '13 at 22:26
  • @MarcGravell First, just throwing is not an option, because I want to reduce complexity by abstracting everything into one function call like C style. Second, I don't understand what you mean latter statement. Can you explain me a little more? – eonil Jan 26 '13 at 22:28
  • @RaphaëlAlthaus And writing `#pragma` for each occurrence is not an option too because it increases code to write which is just opposite of what I want to do. – eonil Jan 26 '13 at 22:30
  • @Eonil if you know `SomeMethod` throws, but the compiler doesn't know that - then you could just `throw new Whatever()` after that call - it won't get hit anyway – Marc Gravell Jan 26 '13 at 22:30
  • @MarcGravell Unfortunately, it doesn't reduce code amount or complexity too. I know C# has nice attribute like `Conditional` which changes compiler behavior, so I am betting on method-level attribution which will make compiler to treat a function call like a `throw`. – eonil Jan 26 '13 at 22:32
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    Write a method that returns an exception. You can have it perform side-effects as required. – Hans Passant Jan 26 '13 at 22:51
  • http://stackoverflow.com/questions/1999181/is-there-a-standard-never-returns-attribute-for-c-sharp-functions – zahir Jun 19 '14 at 16:22

1 Answers1

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The C# is smart. If you a have a method that returns a values, but you throw an exception then it will not generate a warning. 

int foo(int bar)
{
    if (bar > 0) return bar + 1;
    throw new NotSupportedException(); 
}

No warnings are generated.

However, if it did generate a warning you can use #pragma warning. See http://msdn.microsoft.com/en-us/library/441722ys(v=vs.80).aspx

Richard Schneider
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