Re: cortex-m support?

[Rich Felker <dalias@libc.org>]

On Thu, Dec 15, 2016 at 12:34:00PM -0600, Rob Landley wrote:
> On 12/08/2016 03:11 PM, Rich Felker wrote:
> > On Tue, Dec 06, 2016 at 11:52:29PM -0600, Rob Landley wrote:
> >> Index: src/setjmp/arm/setjmp.S
> >> ===================================================================
> >> --- src/setjmp/arm/setjmp.S	(revision 0)
> >> +++ src/setjmp/arm/setjmp.S	(revision 4920)
> >> @@ -0,0 +1,45 @@
> >> +.global __setjmp
> >> +.global _setjmp
> >> +.global setjmp
> >> +.type __setjmp,%function
> >> +.type _setjmp,%function
> >> +.type setjmp,%function
> >> +__setjmp:
> >> +_setjmp:
> >> +setjmp:
> >> +	mov ip,r0
> >> +#if defined(__thumb__)
> >> +	stmia ip!,{v1,v2,v3,v4,v5,v6,sl,fp,lr}
> >> +        str sp, [ip], #4
> >> +#else
> >> +	stmia ip!,{v1,v2,v3,v4,v5,v6,sl,fp,sp,lr}
> >> +#endif
> > 
> > My leaning is to just always use the version that works on thumb,
> 
> Presumaby there's a longjmp.S bit too because:
> 
>         ldmia ip!, {v1,v2,v3,v4,v5,v6,sl,fp,sp,lr}
> 
> Make sure you're aware of erratum 752419:
> 
>   https://sourceware.org/ml/binutils/2011-05/msg00087.html

Thanks. I wasn't aware of this. But my proposed version of the patch
is already immune; it doesn't use ldr to sp, but instead ldm to a temp
register followed by mov to sp. I grepped for ldr to sp and did not
find any instances that are incrementing forms.

Rich