------- Comment #6 from paolo dot carlini at oracle dot com 2008-07-11 21:21 ------- (In reply to comment #5) > Isn't this the kind of thing that -Wstrict-aliasing or -Wstrict-aliasing=n > should warn about?
Hi Benjamin. My guess is that any possible problem can only have to do with some long standing weaknesses that we have in basic_string and we have big troubles changing without breaking the ABI. Back when #pragma system header didn't work with templates we suppressed a "may" aliasing warning in _S_empty_rep (see comment), and there are chances it may have created actual problems in 4_2-branch, per this PR. Currently, AFAIK, isn't possible to reproduce such problems (Ian committed in 4_3 and mainline very important aliasing-related fixes). Anyway, for the record, this patch of mine: http://gcc.gnu.org/ml/libstdc++/2008-07/msg00051.html fixes this problem in 4_2-branch, passes abi-check. I think it's safe, I don't think code linking vs the amended library can tell that the exported _S_empty_rep_storage array changed type, because it's the same size and the same alignment. If you can double-check may analysis we could imagine committing it, somewhere. -- paolo dot carlini at oracle dot com changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |bkoz at redhat dot com Last reconfirmed|2008-07-06 13:40:43 |2008-07-11 21:21:42 date| | http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36742
