[Bug c++/54413] Option for turning off compiler extensions for -std=c++11 with respect to complex/fixed-point numbers missing

["3dw4rd at verizon dot net" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54413

--- Comment #5 from Ed Smith-Rowland <3dw4rd at verizon dot net> 2012-10-01 18:47:33 UTC ---
If I remember correctly, we are supposed to parse compiler-specific extensions
before UDLs - i.e.  The compiler extensions get dibs.  

I guess that's not the issue.  You propose being able to turn off (presumably
all?) gcc-specific suffix extensions.  Presumably, these should be on by
default for C++1*?  I agree we should have something like this.

Detecting at the level of c-family or the lexer whether c++ has seen a
definition of operator"" r or i could be ... real interesting.

Perhaps we could "move" these gnu extensions to:
namespace __gnucxx{
  operator"" r()
}
somehow.