[gcc r13-6887] Remove Negative(gwarf-) from gdwarf

[gcc r13-6887] Remove Negative(gwarf-) from gdwarf

[Richard Biener]

https://gcc.gnu.org/g:33312336d576a0aaa4f425686d652b09151a7c24

commit r13-6887-g33312336d576a0aaa4f425686d652b09151a7c24
Author: Richard Biener <rguenther@suse.de>
Date:   Fri Mar 24 10:19:55 2023 +0100

    Remove Negative(gwarf-) from gdwarf
    
    Prior to the removal of STABS support the gdwarf, gstabs, ... options
    formed a cycle with their Negative(..) option attribute.  But that
    didn't actually have any effect since most of the options also
    are Joined or JoinedOrMissing for which there's no pruning of options
    and so once ran into the set_debug_level diagnostics reporting
    conflicting debug formats.
    
    The following removes the remains of that cycle, which is a
    Negative option from gdwarf to gdwarf-.  With RejectNegative
    added the expected effect of -gdwarf-4 -gdwarf would be to
    enable DWARF5 support (but this doesn't happen for some reason).
    I think the more sensible behavior is that seen and implemented
    in opts.cc, the more specific -gdwarf-4 determines the DWARF level
    and a later or earlier -gdwarf becomes a no-op.  So the
    Negative(..) annotation on gdwarf is just confusing.
    
            * common.opt (gdwarf): Remove Negative(gdwarf-).

Diff:
---
 gcc/common.opt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/common.opt b/gcc/common.opt
index 4546acb5b81..862c474d3c8 100644
--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -3349,7 +3349,7 @@ Common Driver RejectNegative JoinedOrMissing
 Generate BTF debug information at default level.
 
 gdwarf
-Common Driver JoinedOrMissing Negative(gdwarf-) RejectNegative
+Common Driver JoinedOrMissing RejectNegative
 Generate debug information in default version of DWARF format.
 
 gdwarf-