compiler-warning-level-4-c4670.md

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Learn more about: Compiler Warning (level 4) C4670	Compiler Warning (level 4) C4670	11/04/2016	C4670	C4670	e172b134-b1fb-4dfe-8e9d-209ea08b73c7

Compiler Warning (level 4) C4670

'identifier' : this base class is inaccessible

The specified base class of an object to be thrown in a try block is not accessible. The object cannot be instantiated if it is thrown. Check that the base class is inherited with the correct access specifier.

The following sample generates C4670:

// C4670.cpp
// compile with: /EHsc /W4
class A
{
};

class B : /* public */ A
{
} b;   // inherits A with private access by default

int main()
{
    try
    {
       throw b;   // C4670
    }
    catch( B )
    {
    }
}