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Re: m68k softfloat builds

In article <>, Kurt J. Lidl 
<> wrote:
>A while ago, I ran into a problem trying to build a m68k system
>with -msoft-float.  A reply about the failure is here:
>Any thoughts about whether or not this is the best way to procede?

The patch referenced there should be applied regardless if we don't have it

>I suppose that turning on something like the multilib support in gcc
>is another way of doing this -- at least that is my understanding
>of it.
>I think this is a larger relevance than just the existing m68k ports
>too.  The Freescale Coldfire chips (the 54xx and 54xxx) have an
>MMU but none have a floating point unit.  The gcc 4.3 compiler
>has support for the coldfire instruction sets (there are slight
>differences between them all).  I've fooled around a bit with
>trying to get gcc 4.3 to build as a cross compiler for netbsd-current,
>but haven't had any success yet.
>If anybody wants to get netbsd running on the coldfire (I certainly
>do), I think that this whole issue of no-fpu 68k-ish systems will
>need to be addressed.

We have many choices:
1. always put the softfloat glue in libgcc; pros: no magic library selection,
   easier build process. cons: some size overhead in libgcc [I don't think it
   is much].
2. build the softfloat glue only on machines that need it; pros: efficient.
   cons: complex build process, need to figure out crosscompiling, different
   userland flavors for the same platform.
3. build the softfloat glue in a separate library, and auto-load it using magic. pros: efficient. cons: more complicated than building a
   single library, relies on magic.

My order of preference is best to worst 1, 3, 2. Others? Other ideas?


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