https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87274
--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> --- This is not a bug. If you want to use the non-standard extensions in <quadmath.h> then either use -std=gnu++11 instead of -std=c++11, or use -fext-numeric-literals to enable the non-standard suffixes, as suggested. Using -std=c++11 says you want to disable GNU extensions that conflict with ISO C++11.
