Lpc2000

Tom Walsh wrote:
> Sten wrote:
> 
> 
>>Hello Tom,
>>
>>some days ago I discovered a GCC bug on interrupt service routines for functions with
>>__attribute__((interrupt("IRQ"))). At GCC-Bugzilla I found that this bug has still been reported in
>>2005 under bug report #16634 in which you are involved in. Do you know why this bug is still
>>"UNCONFIRMED"?!?
>>
>>The bug still persists in:
>>arm-elf-gcc (GCC) 4.0.1
>>arm-elf-gcc (GCC) 4.1.0
>>
>>Do you (or somebody else) have a gcc-patch to solve this problem? I took a look to the gcc sources
>>by myself but the problem occurs in conjunction with optimization under conditions, where LR
>>register is used for subroutine branches, and this could a little bit more tricky to solve it than
>>just hacking the ARM section of GCC!
>>
>>Can somebody confirm this bug in the binary-tool-chain from www.gnuarm.com or on other GCC-based
>>cross compiler versions? It seems gnuarm don't have any special patches against this problem, too.
>>(See test-case below!)
>> 
>>
> 
> I am not sure what your question is. Why do you feel you have to 
> intentionally suppress the apcs stack frame?
> 

With -mapcs-frame the code produced looks good but due to the APCS a lot of overhead at entry and
exit of my functions is generated. Without that option (or with -mno-apcs-frame) gcc generates wrong
entry/exit code but the code footprint is more slim.
In my opinion an arm-elf-gcc should produce correct code for ARM cores in any case.

GCC manual says for ARM option -mapcs-frame:
"Generate a stack frame that is compliant with the ARM Procedure Call Standard for all functions,
even if this is not strictly necessary for correct execution of the code."

My question was if you know something about the detailed status of bug report #16634? I'm wondering
why it is still UNCONFIRMED since 2005.

Maybe there is somebody out there, who knows something about a patch to fix this problem in GCC
directly.

Regards,
  Sten

-- 
/************************************************
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************************************************/