[Bug 1815057] Update Released
Ćukasz Zemczak
1815057 at bugs.launchpad.net
Mon Apr 29 19:04:57 UTC 2019
The verification of the Stable Release Update for gcc-8 has completed
successfully and the package has now been released to -updates.
Subsequently, the Ubuntu Stable Release Updates Team is being
unsubscribed and will not receive messages about this bug report. In
the event that you encounter a regression using the package from
-updates please report a new bug using ubuntu-bug and tag the bug report
regression-update so we can easily find any regressions.
--
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to gcc-8 in Ubuntu.
https://bugs.launchpad.net/bugs/1815057
Title:
[UBUNTU] GCC Wrong code generate for floating point workloads Ubuntu
18.04
Status in Ubuntu on IBM z Systems:
Fix Committed
Status in gcc-7 package in Ubuntu:
Fix Released
Status in gcc-8 package in Ubuntu:
Fix Released
Status in gcc-7 source package in Bionic:
Fix Committed
Status in gcc-8 source package in Bionic:
Fix Committed
Status in gcc-7 source package in Cosmic:
Fix Committed
Status in gcc-8 source package in Cosmic:
Fix Released
Bug description:
An IBM Z GCC backend problem leads to wrong code being generated for
some floating point workloads.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88856
A patch has been committed to the GCC 7 and 8 upstream branch and
needs to be picked up for the Ubuntu 18.04 compiler.
https://gcc.gnu.org/viewcvs/gcc?view=revision&revision=268551
This change might require rebuilding floating point related packages.
Although the actual problem is hard to trigger. I could only reproduce
it in case if conversion introduces load on condition instructions in
the ce2 pass. The testcase I've looked into came from the python scipy
package which builds with -funroll-loops. The load on condition
opportunity in that case was introduced with the RTL loop unrolling.
This made the split1 pass to use the problematic splitter generating
wrong code in the end.
According to https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=915738
The patch has been picked up for gcc-8 8.2.0-18 already
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu-z-systems/+bug/1815057/+subscriptions
More information about the foundations-bugs
mailing list