[Bug c/106087] New: Segmentation fault in GIMPLE pass: ccp

[nyh at math dot technion.ac.il]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106087

            Bug ID: 106087
           Summary: Segmentation fault in GIMPLE pass: ccp
           Product: gcc
           Version: 9.1.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: nyh at math dot technion.ac.il
  Target Milestone: ---

When building the attached file, part of the open-source OSv project, in gcc
12.1.1 (on Fedora 36), I get:


during GIMPLE pass: ccp
bsd/sys/dev/hyperv/vmbus/hyperv.cc: In function ‘bool hyperv_identify()’:
bsd/sys/dev/hyperv/vmbus/hyperv.cc:117:1: internal compiler error: Segmentation
fault
  117 | hyperv_identify()
      | ^~~~~~~~~~~~~~~
Please submit a full bug report, with preprocessed source.
See <http://bugzilla.redhat.com/bugzilla> for instructions.
Preprocessed source stored into /tmp/ccCg8LNL.out file, please attach this to
your bugreport.

The preprocessed source file is attached.

I discovered that removing the two static variables hyperv_pm_features and
hyperv_features3 makes the compilation succeed. These two variables are static,
and are only set by the function which failed compilation and never read
anywhere else in the source file, so these variables are not needed. So I would
have accepted a warning about them being unused - but not a compiler crash.