Upstream bug/PR 66343: UBSan sometimes generates broken code

[Christian Henz]

gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609

Ran into this today - under certain circumstances, "-fsanitize=undefined" generates ambiguous local labels so that the code cannot be assembled.

This is already fixed upstream, also backported to the gcc-5-branch, but not released as of today.

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66343

[Launchpad Janitor (janitor)]

This bug was fixed in the package gcc-5 - 5.4.1-12ubuntu2

---------------
gcc-5 (5.4.1-12ubuntu2) artful; urgency=medium

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

gcc-5 (5.4.1-12) unstable; urgency=medium

  * Update to SVN 20170820 (r251205, 5.4.1) from the gcc-5-branch.
    - Fix PR libgomp/80394, PR sanitizer/77396, PR sanitizer/80166,
      PR c++/78761, PR gcov-profile/78783, PR c++/79641, PR c/80097,
      PR c++/79512, PR c/77767, PR c/67410, PR c/72816, PR libgomp/80394,
      PR rtl-optimization/80385, PR target/80286 (x86), PR debug/80025,
      PR sanitizer/80168, PR rtl-optimization/80112, PR c++/80129,
      PR sanitizer/79944, PR target/79932 (x86), PR target/79932 (x86),
      PR rtl-optimization/79901, PR rtl-optimization/79901, PR target/79807,
      PR target/79729 (x86), PR middle-end/79396, PR target/79570,
      PR target/79494 (x86), PR target/79568 (x86), PR target/79559 (x86),
      PR tree-optimization/79411, PR middle-end/79399, PR target/79197 (PPC),
      PR ipa/77905, PR target/78796 (AArch64), PR fortran/78298,
      PR middle-end/69183, PR middle-end/78416, PR middle-end/67335,
      PR rtl-optimization/78378, PR target/78227 (x86), PR sanitizer/66343,
      PR rtl-optimization/77919, PR fortran/77665, PR middle-end/77624,
      PR target/77587, PR middle-end/77594, PR sanitizer/68260,
      PR fortran/77516, PR debug/77363, PR middle-end/77377, PR target/71910,
      PR tree-optimization/72824, PR tree-optimization/72824,
      PR sanitizer/71953, PR middle-end/79931, PR ipa/65972, PR lto/50345,
      PR gcov-profile/78783, PR gcov-profile/80413, PR ipa/80212,
      PR sanitizer/70878, PR gcov-profile/80224, PR ipa/80205, PR ipa/80104,
      PR c++/80363, PR c++/80176, PR c++/80141, PR c++/79896, PR c++/79664,
      PR c++/79512, PR c++/78341, PR c++/78949, PR c++/78649, PR c++/77739,
      PR c++/77285, PR c++/78089, PR c++/77467, PR c++/77722, PR c++/77637,
      PR c++/77375, PR c++/72868, PR fortran/78866, PR fortran/77666,
      PR fortran/77500, PR middle-end/50199, PR sanitizer/78992,
      PR sanitizer/78532, PR libstdc++/81002, PR c/81006, PR target/81894 (x86),
      PR target/81861 (x86), PR tree-optimization/81354, PR sanitizer/81604,
      PR tree-optimization/81555, PR tree-optimization/81556,
      PR tree-optimization/81162, PR target/80569 (x86), PR target/81471 (x86),
      PR target/81375 (x86), PR target/81300 (x86), PR tree-optimization/81192,
      PR target/80382 (PPC), PR target/80966 (PPC), PR rtl-optimization/73650,
      PR target/61729 (PPC), PR target/77850 (PPC), PR target/80382 (PPC),
      PR middle-end/80692, PR target/80966 (PPC), PR middle-end/80902,
      PR target/79155 (x86), PR other/80909, PR ipa/80663, PR ipa/79850,
      PR driver/31468, PR other/80589, PR gcov-profile/53915, PR driver/56469,
      PR target/80968 (SPARC), PR target/80968 (SPARC), PR c/81006,
      PR fortran/70601.
    - Fix PR sanitizer/66343. LP: #1704401.
  * Don't build the gc enabled libobjc for cross compilers. Closes: #872233.
  * Fix hangs w/ asan binaries on arm64 (Dann Frazier). LP: #1709727.
  * Linaro branch only: Fix PR target/79041, aarch64 backend em...