[Bug c++/55425] constexpr does not work in many situations (both built-in and user supplied literals)

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55425



Jakub Jelinek <jakub at gcc dot gnu.org> changed:



           What    |Removed                     |Added

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                 CC|                            |jakub at gcc dot gnu.org



--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-11-21 
13:50:43 UTC ---

Or more efficiently

constexpr unsigned int

bin_number (const char *c, unsigned int x)

{

  return *c ? bin_number (c + 1, (x << 1) + (*c == '0' || *c == '1' ? *c - '0'

: throw 0)) : x;

}



constexpr unsigned int

operator"" _bin (const char *c)

{

  return bin_number (c, 0);

}