Re: [CRIS] dwarf2 frame sniffer problem?

[Orjan Friberg <orjan.friberg@axis.com>]

Andrew Cagney wrote:
> 
> Does this:
> 
>         /* 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.  */
>         if (fs->regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED)
>           complaint (&symfile_complaints,
>                      "Incomplete CFI data; unspecified registers at 0x%s",
>                      paddr (fs->pc));
>         else
>           cache->reg[regnum] = fs->regs.reg[column];
> 
> sound like your problem?  It's possible to specify initial values of 
> such registers with:

I do get that complaint, and it seems a lot of registers are set to 
DWARF2_FRAME_REG_UNSPECIFIED.

> /* Set the architecture-specific register state initialization
>    function for GDBARCH to INIT_REG.  */
> 
> extern void dwarf2_frame_set_init_reg (struct gdbarch *gdbarch,
>                                        void (*init_reg) (struct gdbarch 
> *, int,
>                                              struct 
> dwarf2_frame_state_reg *));

Thanks for the tip, I hadn't seen that.  Reading the s390 implementation 
of dwarf2_frame_init_reg I get the impression that that information 
should have been there from the beginning (emitted by gcc that is) since 
it seems to be ABI/calling convention related.  But I'll try and 
implement something similar.

-- 
Orjan Friberg
Axis Communications