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Re: [MiNT] PML trouble with -m68020-60



Vincent Rivière wrote:
I noticed these problems last year when compiling POV-Ray. The 68000 and
ColdFire versions worked well (return to d0/d1), while the -m68020-60
produced almost black pictures. I think it is a good testcase :-)

I have patched PML to match the current GCC behavior with -m68020-60, I believe I did it right... but the result is still wrong.

Then I have discovered something surprising... PML uses some math support functions provided by the MiNTLib, such as ldexp().

And the MiNTLib is wrong for 2 reasons :
- it tests the wrong define for detecting the FPU presence
- when the FPU is present, it returns to d0/d1 instead of fp0

Also, when compiling with -m68020-60:
- GCC 2.95.3 sets __M68881__
- GCC 4.x sets __HAVE_68881__

Big mess.
I'm going to more tests and provide patches, but this will take time.

--
Vincent Rivière