Note: This is a public test instance of Red Hat Bugzilla. The data contained within is a snapshot of the live data so any changes you make will not be reflected in the production Bugzilla. Email is disabled so feel free to test any aspect of the site that you want. File any problems you find or give feedback at bugzilla.redhat.com.
Bug 1536431 - redhat-rpm-config: Be more explicit about -fasynchronous-unwind-tables
Summary: redhat-rpm-config: Be more explicit about -fasynchronous-unwind-tables
Keywords:
Status: CLOSED RAWHIDE
Alias: None
Product: Fedora
Classification: Fedora
Component: redhat-rpm-config
Version: rawhide
Hardware: Unspecified
OS: Unspecified
unspecified
unspecified
Target Milestone: ---
Assignee: Florian Weimer
QA Contact: Fedora Extras Quality Assurance
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2018-01-19 12:23 UTC by Florian Weimer
Modified: 2018-03-02 09:28 UTC (History)
11 users (show)

Fixed In Version: redhat-rpm-config-82-1.fc28
Doc Type: If docs needed, set a value
Doc Text:
Clone Of:
Environment:
Last Closed: 2018-01-22 15:03:02 UTC
Type: Bug
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Bugzilla 1548847 0 unspecified CLOSED gcc: Generate unwind tables by default on ppc64, ppc64le 2022-05-16 11:32:56 UTC
Red Hat Bugzilla 1550914 0 unspecified CLOSED glibc: Missing unwind tables on ppc64, ppc64le 2022-05-16 11:32:56 UTC

Internal Links: 1548847 1550914

Description Florian Weimer 2018-01-19 12:23:21 UTC 
Upstream GCC enables the flag on i686, x86-64, s390x, and we patch it in for aarch64.  ppc64, ppc64le, armv7hl/armhfp should use it as well.

The flag is needed so that performance/debugging tooling works.  glibc cancellation support needs it as well under certain circumstances.
Comment 1 Jakub Jelinek 2018-01-19 12:26:16 UTC 
Unsure about armv7hl/armhfp, that doesn't use DWARF unwind info, but some EABI stuff, no idea what this option does in that case, maybe nothing, somebody would need to test that.
Comment 2 Florian Weimer 2018-01-22 14:16:47 UTC 
ppc64, ppc64le, armv7hl/armhfp do not need it due to differences in stack management.  Updating summary.
Comment 3 Mark Wielaard 2018-02-25 13:10:41 UTC 
(In reply to Florian Weimer from comment #2)
> ppc64, ppc64le, armv7hl/armhfp do not need it due to differences in stack
> management.  Updating summary.

Disabling this for ppc64/ppc64le (in glibc) seems to have caused a regression causing the elfutils testsuite to be unable to unwind in some cases because of missing CFI in the .eh_frame (CFI only being available through .debug_frame in the external debuginfo package) for glibc functions like raise. See e.g. https://koji.fedoraproject.org/koji/taskinfo?taskID=23812571
Comment 4 Mark Wielaard 2018-02-25 13:12:14 UTC 
(In reply to Mark Wielaard from comment #3)
> (In reply to Florian Weimer from comment #2)
> > ppc64, ppc64le, armv7hl/armhfp do not need it due to differences in stack
> > management.  Updating summary.
> 
> Disabling this for ppc64/ppc64le (in glibc) seems to have caused a
> regression causing the elfutils testsuite to be unable to unwind in some
> cases because of missing CFI in the .eh_frame (CFI only being available
> through .debug_frame in the external debuginfo package) for glibc functions
> like raise. See e.g.
> https://koji.fedoraproject.org/koji/taskinfo?taskID=23812571

Note that this might actually be glibc specific, since this happens on recent f27 too.
Comment 5 Florian Weimer 2018-02-25 13:20:50 UTC 
I filed bug 1548847 against Fedora gcc.  The expectation is that redhat-rpm-config follows the GCC defaults in this area.
Note You need to log in before you can comment on or make changes to this bug.