While we're here, fix Syscall9 on NetBSD and OpenBSD:
it was storing the results into the wrong memory locations.
I guess no one uses that function's results on those systems.
Part of cleaning up stack traces and argument frame information.
R=golang-dev, dvyukov
CC=golang-dev
https://golang.org/cl/11355044
Change 231af8ac63aa (CL 7314062) made runtime.enteryscall()
set m->mcache = nil, which means that we can no longer use
syscall.errstr in syscall.Syscall and syscall.Syscall6, since it
requires a new buffer to be allocated for holding the error string.
Instead, we use pre-allocated per-M storage to hold error strings
from syscalls made while in entersyscall mode, and call
runtime.findnull to calculate the lengths.
Fixes#4994.
R=rsc, rminnich, ality, dvyukov, rminnich, r
CC=golang-dev
https://golang.org/cl/7567043
Syscalls return `-1' on error and the representation is always
32-bits. The `$-1' literal in 64-bit assembly is always the
64-bit representation. So this change makes sure that we
always do a 32-bit comparison when checking for error.
Also makes sure that in the error case, we return a 64-bit
`-1' from runtime.seek.
Fixes the arithmetic for handling the error-string in
runtime.Syscall6.
R=golang-dev, rminnich, rsc, ality, minux.ma
CC=golang-dev
https://golang.org/cl/7399052
Offsets for return values from seek were miscalculated
and a translation from 32-bit code for error handling
was incorrect.
R=rsc, rminnich, npe
CC=golang-dev
https://golang.org/cl/7181045
This set of changes extends the Plan 9 support
to include the AMD64 architecture and should
work on all versions of Plan 9.
R=golang-dev, rminnich, noah.evans, rsc, minux.ma, npe
CC=akskuma, golang-dev, jfflore, noah.evans
https://golang.org/cl/6479052
