RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

This bug was initially created as a copy of Bug #2211506

I am copying this bug because: 



User is experiencing the issue in upstream bug report
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99074
[gcc 8 and above is crashing with dynamic_cast<>() on null pointer with optimization level -O1 and above]
and would like a backport for gcc-toolset-9-gcc-9.2* as it is being used
for their product.

While it is agreed it is UB, previous source code relied on this working.

While GCC Toolset 11 is still supported, the fix is for libstdc++.so.6, which is not included in the toolset.
The fix will happen to be included in the next update of the system GCC in RHEL 9 (but currently I have no
plans to rebuild the system gcc in RHEL8).

*** Bug 2211509 has been marked as a duplicate of this bug. ***