[Bug target/52441] SH Target: Double sign/zero extensions for function arguments

olegendo at gcc dot gnu.org gcc-bugzilla@gcc.gnu.org
Thu Mar 1 22:14:00 GMT 2012


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52441

Oleg Endo <olegendo at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2012-03-01
         AssignedTo|unassigned at gcc dot       |olegendo at gcc dot gnu.org
                   |gnu.org                     |
     Ever Confirmed|0                           |1

--- Comment #2 from Oleg Endo <olegendo at gcc dot gnu.org> 2012-03-01 22:13:23 UTC ---
(In reply to comment #1)
> 
> I don't know any historical reason but x86 uses that double sign/zero
> extension too.  It wouldn't be a safe ABI change.  There can exist hand
> written functions depending that behavior.  It's too late to change
> the default behavior, I think.  Of course, you can add a new -m option
> or function attribute changing it, though it shouldn't be default for
> non Renesas ABI.

Right, thanks!  I haven't thought of the hand-written asm code scenario.  This
can turn into a funny problem indeed.

I'll go the option way, then.



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