MVME5500 broken with gcc-4.0.2

Kate Feng feng1 at
Tue Nov 1 13:20:40 UTC 2005

Till Straumann wrote:

> rtems/gcc (implicitely) uses -maltivec on all 74xx CPUS and
> the MVME5500 calls for -mcpu=7450.

The 7455 CPU on the mvme5500 is a lot closer to 7450.

> Unfortunately, with -maltivec, gcc uses vector registers for
> some optimizations.
> --> until proper altivec support is implemented in RTEMS random
>      *data corruption* must be expected.
> Workaround:
> make/custom/mvme5500: use -mcpu=750

I can't remember what problems I had with 750.  Can
rtems/gcc-4.0.2  remove  -maltivec on all 74xx CPUS ?
I thought it's better to leave -maltive  as a BSP
option.   Which RTEMS version has implemented
altivec in 74xx CPUs ?


> -- Till

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