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[MiNT] -m68030 vs -m68020-60



Hi,

I've bumped into this issue by concidence. I think implementation of the -m68xxx flags isn't 100% as described in the man page:

-m68030
Generate output for a 68030.  This is the default when the compiler is configured for 68030-based systems.  It is equivalent to -march=68030.

-m68020-60
Generate output for a 68060, without using any of the new instructions.  This results in code that can run relatively efficiently on either a 68020/68881 or a 68030 or a
68040.  The generated code does use the 68881 instructions that are emulated on the 68060.

-march=arch
Generate code for a specific M680x0 or ColdFire instruction set architecture. 

But in reality what happens is that -m68030 is only alias for -m68020-60. So if you multiply two float numbers, fxxx instructions are generated. Of course, this can be overriden by -msoft-float but that's not the point. I'd imagine that if I specify that I want code for 68030, it wont generate it for FPU.

--
MiKRO / Mystic Bytes
http://mikro.atari.org