[Bug bootstrap/58340] [4.9 regression] gcc/cp/pt.c:7064:1: internal compiler error: in propagate_threaded_block_debug_into, at tree-ssa-threadedge.c:623

[law at redhat dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58340

--- Comment #18 from Jeffrey A. Law <law at redhat dot com> ---
I'm seeing ia64 fail with an insn does not match constraints failure when the
stage2 compiler builds the stage2 C++ runtime.  And that's *with* the fix I
checked in last night.  That smells like stage1 mis-compiled stage2.

So I'm going to keep this open while I track down that regression.

There's another ICE I'm aware of (pr58343), but I don't see the root cause of
that PR causing a mis-compilation, just ICEs for certain degenerate cases.