[Bug libstdc++/86112] New: Python printers don't work on Python 2.6

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86112

            Bug ID: 86112
           Summary: Python printers don't work on Python 2.6
           Product: gcc
           Version: 8.1.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: redi at gcc dot gnu.org
  Target Milestone: ---

Traceback (most recent call last):
  File "blah/libstdc++.so.6.0.25-gdb.py", line 61, in <module>
    register_libstdcxx_printers(gdb.current_objfile())
  File "blah/../share/gcc-8.1.0/python/libstdcxx/v6/__init__.py", line 28, in
register_libstdcxx_printers
    from .printers import register_libstdcxx_printers
  File "blah/../share/gcc-8.1.0/python/libstdcxx/v6/printers.py", line 1441
    defargs = { n: d.replace('std::', ns) for n,d in defargs.items() }
                                            ^
SyntaxError: invalid syntax

The dict comprehension syntax is only supported from Python 2.7 onwards.

It needs to be:

  defargs = dict((n, d.replace('std::', ns)) for  (n,d) in defargs.items())