[Bug c++/99610] GCC thinks member function template is a deduction guide

[gcchelp.5.adept at 0sg dot net via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99610

--- Comment #1 from Christian Schüler <gcchelp.5.adept at 0sg dot net> ---
There is a workaround
declaring the function Hash with trailing return will make the error go away.

    template< typename X >
    auto Hash( const X &arg ) const -> unsigned
         { ... }