On Mon, Oct 6, 2014 at 12:16 PM, Eric Botcazou <ebotca...@adacore.com> wrote: > Hi, > > this is a regression from GCC 4.8.x: gnat1 (uintp.adb:UI_Lt) is miscompiled > during a LTO boostrap when Init_Operand is inlined into it. A store is > wrongly deleted by GIMPLE DSE because of a missed aliasing relationship > between 2 array types with TYPE_NONALIASED_COMPONENT set, one being a derived > of the other in Ada, hence the latter being allowed to alias the former. > > Tested on x86_64-suse-linux, OK for the mainline and 4.9 branch?
Testcase? I think it would be better to handle this in the canonical type merging code in lto.c - or how does it end up working without LTO? That is, what does the Ada frontend do to make sure get_alias_set handles this correctly? Thanks, Richard. > > 2014-10-06 Eric Botcazou <ebotca...@adacore.com> > > * gimple.c (gimple_get_alias_set): Return 0 for array types with non- > aliased component and that contain PLACEHOLDER_EXPRs. > > > -- > Eric Botcazou
