[Bug c++/60249] [c++11] Compiler goes into semi-infinite loop with wrong usage of user defined string literals

[3dw4rd at verizon dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60249

--- Comment #4 from Ed Smith-Rowland <3dw4rd at verizon dot net> ---
Created attachment 33022
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=33022&action=edit
Patch 58781, 59867, 60249, ...

I think I got it.

Don't mess with the token stream.

PR C++/58781 - Unicode strings broken in a strange way
PR C++/59867 - Template string literal loses first symbol
PR C++/60249 - Compiler goes into semi-infinite loop with wrong usage of user
defined string literals
Plus I fixed an misleading error message for string literal operator templates
(not available in C++11).