libc/libstand for RISC-V

[br]

Replace "This software..." with "Portions of this software..."

[andrew]

lib/libc/riscv/_fpmath.h

39

I should check the packing :-)

lib/libc/xdr/xdr_float.c

63–64

I've been wondering why this exists, all architectures we support (and some we don't) are listed here.

[kib]

lib/libc/xdr/xdr_float.c

63–64

I suspect that ppc64 isn't. The code was written by Sun and then not sanitized.

[andrew]

lib/libc/xdr/xdr_float.c

63–64

I thought (and @jhibbits confirmed) that __ppc__ was defined when building for ppc64.

[emaste]

lib/libc/xdr/xdr_float.c

63–64

Agree, the #if should just be removed.

lib/libstand/Makefile

78–81

perhaps combine aarch64 and riscv case into

.PATH ${LIBC_SRC}/${MACHINE_CPUARCH}/gen

[br]

• arith.h and gd_qnan.h regenerated;
• architectures check in lib/libc/xdr/xdr_float.c removed;
• aarch64 and riscv cases in libstand/Makefile combined.

[andrew]

lib/libc/xdr/xdr_float.c

63–64

I've built a similar change where I also removed all the Vax code. Without it this file is much simpler. I'm happy with just removing the #if for now.