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Is a pointer to the return-value of the typeid operator always valid in C++?

December 8, 2023

I assume it is the case, because e.g. &typeid(int) should be known already at compile-time, i.e. the pointer should never be invalidated when running out of any scope.

Example:
If my assumption is correct, then the following code should not lead to any undefined behavior (at least it works on my PC).

int main() {
    const std::type_info* pType = nullptr; 
    {
        pType = &typeid(int);
    }
    std::cout << pType->name() << std::endl;
}

My goal:
Let’s say I have a class called MyTest defined as follows.

struct MyTest {
    const std::type_info* pType;
    MyTest(const std::type_info& type) : pType(&type) {}
    void printType() { std::cout << pType->name() << std::endl; }
};

Then the following code should hopefully lead to no undefined behavior, even when the argument in the constructor of MyTest is just "local".

int main() {
    MyTest myTest(typeid(double));
    myTest.printType();
}

I know there is another thread about whether you can compare two types by comparing the pointers to the return value of typeid, but that is not my problem here.