[Bug rtl-optimization/77844] [5/7 Regression] Compilation of simple C++ example exhaust memory

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77844

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |compile-time-hog
                 CC|                            |aoliva at gcc dot gnu.org,
                   |                            |jakub at gcc dot gnu.org
          Component|middle-end                  |rtl-optimization

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
It's fast with -fno-var-tracking.  We have lots of cse-lim stuff in test()
which gets down to a single BB with lots of DEBUG stmts (mostly resets).  I
suspect a previous missed optimization became "latent" again (optimizing to a
single BB again).  And we're running into one of the var-tracking limits (on
expr depth I assume).

Interestingly with max-vartrack-size == 1 we still run into the compile-time
isse.

I suppose the data-flow problem doesn't converge.