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/Zc:gotoScope (Enforce conformance in goto scope)

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The /Zc:gotoScope compiler option enables checks for Standard C++ behavior around goto statements that jump over the initialization of local variables.

Syntax

/Zc:gotoScope[-]

Remarks

The /Zc:gotoScope compiler option enforces C++ Standard behavior around goto statements that jump over the initialization of one or more local variables. The compiler emits error C2362 in all such cases when /Zc:gotoScope is specified. The /Zc:gotoScope- relaxes this check, but the compiler still emits an error if a goto skips initialization of a local variable that has a non-trivial destructor.

The intent of the /Zc:gotoScope- option is to help ease the migration of older code bases to more conformant code. You may use it to suppress certain errors until you've updated the non-conforming code.

The /Zc:gotoScope compiler option is new in Visual Studio 2022 version 17.4. The option is off by default. It's enabled automatically by the /permissive- option (or an option that implies /permissive-, such as /std:c++20 or /std:c++latest). To enable the error check explicitly, add /Zc:gotoScope to the compiler command line. To explicitly disable the check, use the /Zc:gotoScope- option. The /Zc:gotoScope- must appear after the /permissive- option or any option that implies /permissive-.

Example

This sample generates an error message when compiled using /Zc:gotoScope:

int g(int*);
bool failed(int);

int f() {
    int v1;
    auto result = g(&v1);
    if (failed(result))
        goto OnError;
    int v2 = v1 + 2;
    return v2;
OnError:
    return -1;
}

/* Output:
t.cpp(9): error C2362: initialization of 'v2' is skipped by 'goto OnError'
*/

If the code is compiled with /Zc:gotoScope-, the compiler doesn't emit the error.

Even when /Zc:gotoScope- is specified, the compiler still emits an error if the local variable has a non-trivial destructor. For example:

int g(int*);
bool failed(int);

class S {
public:
    S(int);
    ~S();
    int mf() const;
};

int f()
{
    int v1;
    auto result = g(&v1);
    if (failed(result))
        goto OnError;
    S s(v1);
    return s.mf();

OnError:
    return -1;
}

/* Output:
t.cpp(17): error C2362: initialization of 's' is skipped by 'goto OnError'
*/

To set this compiler option in Visual Studio

  1. Open the project's Property Pages dialog box. For details, see Set C++ compiler and build properties in Visual Studio.

  2. Select the Configuration Properties > C/C++ > Command Line property page.

  3. In Additional options, add /Zc:gotoScope or /Zc:gotoScope-. Choose OK or Apply to save your changes.

See also

/Zc (Conformance)
/permissive-
/std (Specify language standard version)