[Bug libstdc++/85442] New: [8 Regression] cxx11-ios_failure.lo build fails for microblaze

[jsm28 at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85442

            Bug ID: 85442
           Summary: [8 Regression] cxx11-ios_failure.lo build fails for
                    microblaze
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jsm28 at gcc dot gnu.org
                CC: redi at gcc dot gnu.org
  Target Milestone: ---
            Target: microblaze-linux-gnu

My glibc bot building with build-many-glibcs.py shows the libstdc++ build
failing for microblaze:

https://sourceware.org/ml/libc-testresults/2018-q2/msg00051.html

cxx11-ios_failure-lt.s: Assembler messages:
cxx11-ios_failure-lt.s: Fatal error: duplicate .debug_line sections
Makefile:766: recipe for target 'cxx11-ios_failure.lo' failed
make[6]: *** [cxx11-ios_failure.lo] Error 1

Introduced by r259281.  I don't know whether this is a bug in the microblaze
compiler or in the special makefile code that generates this .s file.