sparc erc32 FPU confusion

Aleix Conchillo Flaqué aconchillo at
Wed May 31 09:15:49 UTC 2006

On 31 May 2006, at 10:51, Jiri Gaisler wrote:

> Tasks that are not marked as FPU tasks could therefore trap
> unless they are compiled with lower optimization effort,
> OR with -msoft-float.
> an FPU is present and enabled. The kernel can (and must)
> therefore always be compiled with -msoft-float to avoid
> spurious FPU instructions due to gcc optimizations. If
> your application uses the FPU, these parts should be
> compiled without -msoft-float. If you share code between
> FPU tasks and non-FPU tasks, you must decrease the
> optimization level to avoid unexpected FPU instructions
> as explained above.

So, this means that the kernel can still be compiled with -O4 (like  
before) as it is forcing to not use the FPU with the -msoft-float?

Do you know from which version of gcc this is the behaviour?


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