[Bug c++/52654] [C++11] Warn on overflow in user-defined literals

[3dw4rd at verizon dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52654

--- Comment #9 from Ed Smith-Rowland <3dw4rd at verizon dot net> 2012-04-05 19:30:41 UTC ---
Created attachment 27103
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27103
Patch including testcases - warn and only when necessary on literal overflow.

Pass a flag indicating overflow (or underflow) through the preprocessor and
lexer down to the C++ parser.  Only if a numeric argument literal operator is
found do we finally warn.  Otherwise block all warnings for over/under-flow of
user-defined literals in the preprocessor and lexer.

Waiting for a complete regtest.