[Bug c++/84608] Hang in cxx_eval_constant_expression() with -fsanitize=undefined

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84608

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |compile-time-hog
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2018-02-28
                 CC|                            |jason at gcc dot gnu.org,
                   |                            |nathan at gcc dot gnu.org
     Ever confirmed|0                           |1

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed.  I think potential_constant_expression_1 gets exponential with
lots of SAVE_EXPRs UBSAN introduces here.  It should rather have a visited
map like walk_tree_without_duplicates.