**Describe the bug**

-2147483648 is the minimum integer representable with Int32, but ``toInt32OrNull('-2147483648')`` returns ``NULL``. On the other hand ``toInt32('-2147483648')`` correctly returns ``-2147483648``.

**Does it reproduce on recent release?**

Yes. It happens on 21.7.5.29-stable

**How to reproduce**

```
SELECT
    toInt32('-2147483648'),
    toInt32OrNull('-2147483648')

Query id: 94f4e069-6c0e-44d9-8e94-7ee83b90a529

┌─toInt32('-2147483648')─┬─toInt32OrNull('-2147483648')─┐
│            -2147483648 │                         ᴺᵁᴸᴸ │
└────────────────────────┴──────────────────────────────┘
```

**Expected behavior**

``toInt32('-2147483648')`` and ``toInt32OrNull('-2147483648')`` should both return ``-2147483648``.

{
    switch (c)
    {
        case 'a':
            return '\a';
        case 'b':
            return '\b';
        case 'e':
            return '\x1B';      
        case 'f':
            return '\f';
        case 'n':
            return '\n';
        case 'r':
            return '\r';
        case 't':
            return '\t';
        case 'v':
            return '\v';
        case '0':
            return '\0';
        default:
            return c;
    }
}
inline void readChar(char & x, ReadBuffer & buf)