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title: "Using setjmp-longjmp | Microsoft Docs"
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# Using setjmp/longjmp
When [setjmp](../c-runtime-library/reference/setjmp.md) and [longjmp](../c-runtime-library/reference/longjmp.md) are used together, they provide a way to execute a non-local `goto`. They are typically used to pass execution control to error-handling or recovery code in a previously called routine without using the standard calling or return conventions.  
  
> [!CAUTION]
>  However, because `setjmp` and `longjmp` do not support C++ object semantics, and because they might degrade performance by preventing optimization on local variables, we recommend that you do not use them in C++ programs. We recommend that you use `try`/`catch` constructs instead.  
  
 If you decide to use `setjmp`/`longjmp` in a C++ program, also include SETJMP.H or SETJMPEX.H to assure correct interaction between the functions and C++ exception handling. If you use [/EH](../build/reference/eh-exception-handling-model.md) to compile, destructors for local objects are called during the stack unwind. If you use **/EHs** to compile, and one of your functions calls a function that uses [nothrow](../cpp/nothrow-cpp.md) and the function that uses `nothrow` calls `longjmp`, then the destructor unwind might not occur, depending on the optimizer.  
  
 In portable code, when a non-local `goto` that calls `longjmp` is executed, correct destruction of frame-based objects might be unreliable.  
  
## See Also  
 [Mixing C (Structured) and C++ Exceptions](../cpp/mixing-c-structured-and-cpp-exceptions.md)