[Bug target/65233] [5 Regression] ICE (segfault) on arm-linux-gnueabihf and aarch64-linux-gnu

[law at redhat dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65233

Jeffrey A. Law <law at redhat dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |law at redhat dot com

--- Comment #14 from Jeffrey A. Law <law at redhat dot com> ---
Presumably this is a case where a block has become unreachable?  Or is it a
case where the block previously had multiple preds, then by way of jump
threading we've got just a single pred and ultimately we try to merge it with
its single predecessor?

In the former case, I'd expect cleanup_tree_cfg_noloop (called from
cleanup_tree_cfg) to have removed the unreachable block(s).

Just to be clear, I'm not saying the patch is wrong, I'm just trying to
understand the events that led to a PHI with no args and whether or not it
should have already been cleaned up.