[Bug 1815057] [NEW] [UBUNTU] GCC Wrong code generate for floating point workloads Ubuntu 18.04

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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

** Affects: gcc-8 (Ubuntu)
     Importance: Undecided
     Assignee: Skipper Bug Screeners (skipper-screen-team)
         Status: New


** Tags: architecture-s39064 bugnameltc-175326 severity-high targetmilestone-inin18041
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[UBUNTU] GCC Wrong code generate for floating point workloads Ubuntu 18.04
https://bugs.launchpad.net/bugs/1815057
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