https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94655
Jeffrey A. Law <law at redhat dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Resolution|--- |DUPLICATE
Status|NEW |RESOLVED
CC| |law at redhat dot com
--- Comment #6 from Jeffrey A. Law <law at redhat dot com> ---
Fundamentally if we're relying on the type of the MEM_REF, then we're going to
run into problems. It simply does not map back to what the user originally
wrote. That's the key issue Richi and Jakub are raising.
pr94675 is another recently reported example. In that case as well FRE creates
a MEM_REF from address arithmetic, but the type isn't useful and leads to a
false positive out of bounds array warning. Forwprop can do this stuff as
well, and I suspect if we were to dig elsewhere we'd find more examples.
While I don't want to lose these warnings, they are proving problematical in
the MEM_REF cases and I'm wondering if we need a distinct knob to disable them
in the MEM_REF cases given the fundamental incompatibility between giving good
diagnostics and the actions of various optimization passes.
In the immediate term I'm going to mark this as a dup of 94675 (and any others
I encounter in my BZ wanderings).
*** This bug has been marked as a duplicate of bug 94675 ***
