Incorrect code from EGCS-1.1 on PowerPC

Gary Thomas gdt@linuxppc.org
Wed Aug 19 00:17:00 GMT 1998


On 18-Aug-98 Franz Sirl wrote:
> Am Tue, 18 Aug 1998 schrieb Gary Thomas:
>>>The attached code snippet (from the Linux kernel) generates incorrect
>>code when compiled on Linux/PPC with "-O2" options.
>>
>>The problem stems from inlined functions and a pointer (skb) being
>>dereferenced (skb->sb) before it is tested for NULL as a result of 
>>the loop being reorganized.
> 
> I verified the bug with a cvs checkout 1845UTC 19980818. -fno-schedule-insns
> makes the bug go away.
> 

You reported on the 'egcs' list that the current snapshot is "OK"
for building the latest 2.1.XX kernel.  Don't you see this code generation
error when you build it?  Or is it that pattern sensitive that changes
between 2.0.32 and 2.1.115 keep it from happening?

------------------------------------------------------------------------
Gary Thomas                              |
email: gdt@linuxppc.org                  | "Fine wine is a necessity of
   ... opinions expressed here are mine  |        life for me"
       and no one else would claim them! |
                                         |      Thomas Jefferson
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