incorrect enum value parsing

[houzhengtao]

constexpr   int   BASE = 7;

enum enum_test {
    A = BASE + 10,
    B
};

int test()
{
    return 100 / B;
}

error report :
test_5.cpp:10:16: error: Division by zero. [zerodiv]
        return 100 / B;
                                 ^

Incorrectly parse enum value B into 0 which is really 18.

[CHR]

This does not reproduce in 2.3.