Re: Use DWARF CFI frame unwinder on powerpc

["David S. Miller" <davem@davemloft.net>]

From: Andreas Schwab <schwab@suse.de>
Date: Tue, 09 May 2006 19:46:13 +0200

> That is presumably a gcc problem:
> 
> 	/* NOTE: cagney/2003-09-05: CFI should specify the disposition
> 	   of all debug info registers.  If it doesn't, complain (but
> 	   not too loudly).  It turns out that GCC assumes that an
> 	   unspecified register implies "same value" when CFI (draft
> 	   7) specifies nothing at all.  Such a register could equally
> 	   be interpreted as "undefined".  Also note that this check
> 	   isn't sufficient; it only checks that all registers in the
> 	   range [0 .. max column] are specified, and won't detect
> 	   problems when a debug info register falls outside of the
> 	   table.  We need a way of iterating through all the valid
> 	   DWARF2 register numbers.  */
> 
> Andreas.

I really think this warning message should be off by default,
9 times out of 10 when it triggers the situation is completely
harmless.