internal compiler error: in comparison, at go/gofrontend/expressions.cc:6508

Fixed upstream https://groups.google.com/d/topic/gofrontend-dev/rit51azZQU8/discussion in the 4.9 branch and trunk

fixed in 14.10

libgcc1 updates: libgcc1 had been in use in utopic and vivid without problems. It doesn't add any new functionality, no symbols are removed or added.

looking at the upstream changelog, changes only include bug fixes or slight enhancements. Attached are the changes which affect our release architectures:

2015-02-17 Sandra Loosemore <email address hidden>

        Backported from mainline
        2015-02-17 Sandra Loosemore <email address hidden>

        * config/arm/bpabi.S (test_div_by_zero): Make label names
        consistent between thumb2 and arm mode cases. Separate the
        signed comparison on the high word of the numerator from the
        unsigned comparison on the low word.
        * config/arm/bpabi-v6m.S (test_div_by_zero): Similarly separate
        signed comparison.

2015-02-01 H.J. Lu <email address hidden>

        Backported from mainline
        2015-01-24 H.J. Lu <email address hidden>

        * config/i386/cpuinfo.c (processor_subtypes): Add
        INTEL_COREI7_BROADWELL.
        (get_intel_cpu): Support new Silvermont, Haswell and Broadwell
        model numbers.

2014-09-18 Joseph Myers <email address hidden>

        * config/i386/sfp-machine.h (FP_TRAPPING_EXCEPTIONS): Treat clear
        bits not set bits as indicating trapping exceptions.

2014-08-04 Rohit <email address hidden>

        PR target/60102
        * config/rs6000/linux-unwind.h (ppc_fallback_frame_state): Update
        based on change in SPE high register numbers and 3 HTM registers.

comparing the testsuite runs with the released version, and the proposed version, there are no regressions seen for all builds. The juju-core package was test built using the proposed version.

Hello Dave, or anyone else affected,

Accepted gccgo-4.9 into trusty-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/gccgo-4.9/4.9.3-0ubuntu4 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

I verified the fix in a lxd. Before enabling proposed:

root@trusty:~# gccgo --version
gccgo (Ubuntu 4.9.1-0ubuntu1) 4.9.1
Copyright (C) 2014 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

root@trusty:~# gccgo test.go
In function 'main.$nested1':
go1: internal compiler error: in comparison, at go/gofrontend/expressions.cc:6508
Please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gccgo-4.9/README.Bugs> for instructions.
root@trusty:~#

And after:

root@trusty:~# gccgo --version
gccgo (Ubuntu 4.9.3-0ubuntu4) 4.9.3
Copyright (C) 2015 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

root@trusty:~# gccgo test.go
root@trusty:~#

This bug was fixed in the package gccgo-4.9 - 4.9.3-0ubuntu4

---------------
gccgo-4.9 (4.9.3-0ubuntu4) trusty-proposed; urgency=medium

  * Upload the final GCC 4.9.3 release.
  * Merge changes from gcc-4.9 4.9.3-2ubuntu1, including:
    - Fix PR go/60931, garbage collector issue with non 4kB system page size.
      LP: #1304754.
    - Fix wrong-code issue in the little endian vector API (ppc64el).
      LP: #1311128.
    - Fix ABI incompatibility between POWER and Z HTM builtins and intrinsics.
      LP: #1320292.
    - Fix an ICE with invalid code. PR c++/61046. LP: #1313102.
    - gccgo: Don't overwrite memory if an archive has a bad file name.
    - Fix PR rtl-optimization/61801, sched2 miscompiles syscall sequence with -g.
    - libgo: Fix unexpected GC interfering with closure passing.
    - libgo: Fix PR other/61895, ignore small argv[0] file for backtrace.
    - libgo: Fix unexpected GC interfering with closure passing.
    - Fix ICE in the Go frontend. LP: #1362906.
    - Enable cgo on AArch64 (Michael Hudson). LP: #1361940.
    - libgo: runtime: Use the clone system call on GNU/Linux.
    - libgo: Support arm64 relocations (Michael Hudson).
  * Include the cc1 binary into the gccgo-4.9 package.
  * Do not build-depend on sdt-systemtap for the trusty upload.
  * Warn about ppc ELFv2 ABI issues, which will change in GCC 5.
  * libgo: Fix PR go/67508, rewrite lfstack packing/unpacking to look more
    like that in Go (Michael Hudson). LP: #1472650.

gcc-4.9 (4.9.3-2ubuntu1) wily; urgency=medium

  * Merge with Debian; remaining changes:
    - Build from upstream sources.

gcc-4.9 (4.9.3-2) unstable; urgency=medium

  * Update to SVN 20150714 (r225765) from the gcc-4_9-branch.
  * Update the Linaro support to the 4.9-2015.06 release.

gcc-4.9 (4.9.3-1ubuntu1) wily; urgency=medium

  * Merge with Debian; remaining changes:
    - Build from upstream sources.

gcc-4.9 (4.9.3-1) unstable; urgency=medium

  * GCC 4.9.3 release.
  * Update to SVN 20150629 (r225135) from the gcc-4_9-branch.
  * Refresh patches.

gcc-4.9 (4.9.2-22ubuntu1) wily; urgency=medium

  * Merge with Debian; remaining changes:
    - Build from upstream sources.

gcc-4.9 (4.9.2-22) unstable; urgency=medium

  * Update to SVN 20150623 (r224833) from the gcc-4_9-branch.
  * Fix PR target/66483, taken from the trunk. Closes: #787689.
  * Fix "empty-binary-package" lintian warnings.
  * Fix PR tree-optimization/66233. Closes: #788812.

gcc-4.9 (4.9.2-21) unstable; urgency=medium

  * Update to SVN 20150611 (r224436) from the gcc-4_9-branch.
  * Build libstdc++6 when building the common libraries.

gcc-4.9 (4.9.2-20ubuntu1) wily; urgency=medium

  * Merge with Debian; remaining changes:
    - Build from upstream sources.

gcc-4.9 (4.9.2-20) unstable; urgency=medium

  * Update to SVN 20150531 (r223898) from the gcc-4_9-branch.
  * Fix PR rtl-optimization/63843, taken from the trunk. Closes: #785475.

gcc-4.9 (4.9.2-19ubuntu1) wily; urgency=medium

  * Merge with Debian; remaining changes:
    - Build from upstream sources.

gcc-4.9 (4.9.2-19) unstable; urgency=medium

  * Update to SVN 20150529 (r223861) from the gcc-4_9-branch.
  * Make symbols file symlinking for cross bu...

The verification of the Stable Release Update for gccgo-4.9 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.