https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68197
--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> --- Author: redi Date: Wed May 2 19:04:55 2018 New Revision: 259854 URL: https://gcc.gnu.org/viewcvs?rev=259854&root=gcc&view=rev Log: PR libstdc++/68197 fail on negative iword/pword indices The suggested resolution of LWG 3083 is to make invalid indices undefined, but we can fairly easily check for them and treat them as errors in the same way as allocation failure. This avoids a segfault or worse, setting an error flag on the stream instead. PR libstdc++/68197 * include/bits/ios_base.h (ios_base::iword, ios_base::pword): Cast indices to unsigned. * src/c++11/ios.cc (ios_base::_M_grow_words): Treat negative indices as failure. Refactor error handling. * testsuite/27_io/ios_base/storage/68197.cc: New. Added: trunk/libstdc++-v3/testsuite/27_io/ios_base/storage/68197.cc Modified: trunk/libstdc++-v3/ChangeLog trunk/libstdc++-v3/include/bits/ios_base.h trunk/libstdc++-v3/src/c++11/ios.cc
