auto p = new int[2];

becomes

int * p = new int[22;

The same happens for the decltype(auto) placeholder.
For multidimensional arrays, each index gets screwed, e.g. [2][3] becomes [22[33.
For index ranges > 9, e.g. [123][456], only the first digit is doubled: [1123[4456.
Hexadecimal integer literals screw it even more. new int[0x02] becomes new in2.
Octal integer literals in multidimensional array new expressions also result in a very funny output. new int[02][03] becomes new int 2][3.

Also note the additional newline added after every such declaration.

There is no problem with non-array new expressions and with array new expression when variable type is not deduced.