[Bug target/47269] New: DSYMUTIL_SPEC doesn't handle -gtoggle

[Bug target/47269] New: DSYMUTIL_SPEC doesn't handle -gtoggle

[howarth at nitro dot med.uc.edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47269

           Summary: DSYMUTIL_SPEC doesn't handle -gtoggle
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: howarth@nitro.med.uc.edu


Currently on darwin, DSYMUTIL_SPEC is unaware of the -gtoggle flag. This
results in dsymutil not being called as expected when '-g0 -gtoggle' is passed
to the compiler despite any resulting object files containing the expected
DWARF debug information. It is unclear how we can code for this in
DSYMUTIL_SPEC since -gtoggle needs to invert the final accumulative setting of
-g.

[Bug target/47269] DSYMUTIL_SPEC doesn't handle -gtoggle

[howarth at nitro dot med.uc.edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47269

--- Comment #1 from Jack Howarth <howarth at nitro dot med.uc.edu> 2011-01-13 05:23:00 UTC ---
This seems impossible to implement without the addition of a logical AND to the
spec language and the ability to place parentheses. We have two cases which
have to be tested as true...

(!g0 & !gtoggle) | (g0 & gtoggle)

in order to properly decided if -dsym should be passed.

[Bug target/47269] DSYMUTIL_SPEC doesn't handle -gtoggle

[mikestump at comcast dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47269

--- Comment #2 from Mike Stump <mikestump at comcast dot net> 2011-02-06 01:10:06 UTC ---
Luckily specs can do this:

  %{!fdump=*:%{!fsyntax-only:foo}}

says to put in foo, if those two flags are not given; this is and.

[Bug target/47269] DSYMUTIL_SPEC doesn't handle -gtoggle

[mikestump at comcast dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47269

--- Comment #3 from Mike Stump <mikestump at comcast dot net> 2011-02-06 01:31:52 UTC ---
If I understand what they intend, though, the documentation isn't clear on this
point:

%{!gtoggle:
  %{gdwarf-2:%{!gstabs*:%{!g0: -idsym}}}\                                       
      %{.c|.cc|.C|.cpp|.cp|.c++|.cxx|.CPP|.m|.mm: \                             
      %{gdwarf-2:%{!gstabs*:%{!g0: -dsym}}}}
}

%(gtoggle:
    %{!gdwarf-2:%{!gstabs*:%{!g0: -idsym}}}\                                    
      %{.c|.cc|.C|.cpp|.cp|.c++|.cxx|.CPP|.m|.mm: \                             
      %{!gdwarf-2:%{!gstabs*:%{!g0: -dsym}}}}
}

that said, I'd have the explain in detail exactly what happens with -g0 and
-gstabs.  You'd have to check to {} nesting to make sure I the } at the very
end is right.

[Bug target/47269] DSYMUTIL_SPEC doesn't handle -gtoggle

[howarth at nitro dot med.uc.edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47269

--- Comment #4 from Jack Howarth <howarth at nitro dot med.uc.edu> 2011-02-06 02:15:08 UTC ---
Mike,
   I thought it was pretty clear in the man page...

       -gtoggle
           Turn off generation of debug info, if leaving out this option would
           have generated it, or turn it on at level 2 otherwise.  The
           position of this argument in the command line does not matter, it
           takes effect after all other options are processed, and it does so
           only once, no matter how many times it is given.  This is mainly
           intended to be used with -fcompare-debug.

It inverts whatever the final status of debug code generation was. I think this
is why
you see it handled in toplev.c...

  if (flag_gtoggle)
    {
      if (debug_info_level == DINFO_LEVEL_NONE)
        {
          debug_info_level = DINFO_LEVEL_NORMAL;

          if (write_symbols == NO_DEBUG)
            write_symbols = PREFERRED_DEBUGGING_TYPE;
        }
      else
        debug_info_level = DINFO_LEVEL_NONE;
    }

rather than in opts.c.