Synopsis

(Required) The operand to typeid shall not be an expression of polymorphic class type

Enabled by default

Yes

Severity/Certainty

Medium/Medium

Full description

It is undefined whether such an expression is evaluated in runtime or not.

Coding standards

This check does not correspond to any coding standard rules.

Code examples

The following code example fails the check and will give a warning:

#include <typeinfo>

struct P { virtual void foo() {} }; // Polymorphic

void example( P * p ) {
  auto& t = typeid( *p ); // Non-compliant
}

The following code example passes the check and will not give a warning about this issue:

#include <typeinfo>

struct S { }; // Non-polymorphic

void example( S* s ) {
  auto& t = typeid( *s ); // Compliant
}