which are tied to a specific release.
-->

## Introduction {#intro}

Go's emphasis on backwards compatibility is one of its key strengths.
There are, however, times when we cannot maintain complete compatibility.
If code depends on buggy (including insecure) behavior,
then fixing the bug will break that code.
New features can also have similar impacts:
enabling the HTTP/2 use by the HTTP client broke programs

<code>foo+4(SB)</code> is four bytes past the start of <code>foo</code>.
</p>

<p>
The <code>FP</code> pseudo-register is a virtual frame pointer
used to refer to function arguments.
The compilers maintain a virtual frame pointer and refer to the arguments on the stack as offsets from that pseudo-register.
Thus <code>0(FP)</code> is the first argument to the function,
<code>8(FP)</code> is the second (on a 64-bit machine), and so on.

pkg syscall (freebsd-riscv64), const IP_MF = 8192 #53466
pkg syscall (freebsd-riscv64), const IP_MF ideal-int #53466
pkg syscall (freebsd-riscv64), const IP_MINTTL = 66 #53466
pkg syscall (freebsd-riscv64), const IP_MINTTL ideal-int #53466
pkg syscall (freebsd-riscv64), const IP_MIN_MEMBERSHIPS = 31 #53466
pkg syscall (freebsd-riscv64), const IP_MIN_MEMBERSHIPS ideal-int #53466

pkg syscall (netbsd-arm64-cgo), const IP_MINFRAGSIZE = 69
pkg syscall (netbsd-arm64-cgo), const IP_MINFRAGSIZE ideal-int
pkg syscall (netbsd-arm64-cgo), const IP_MINTTL = 24
pkg syscall (netbsd-arm64-cgo), const IP_MINTTL ideal-int
pkg syscall (netbsd-arm64-cgo), const IP_MSS = 576
pkg syscall (netbsd-arm64-cgo), const IP_MSS ideal-int
pkg syscall (netbsd-arm64-cgo), const IP_MULTICAST_IF = 9

pkg syscall (freebsd-arm64), const IP_MIN_MEMBERSHIPS = 31
pkg syscall (freebsd-arm64), const IP_MIN_MEMBERSHIPS ideal-int
pkg syscall (freebsd-arm64), const IP_MINTTL = 66
pkg syscall (freebsd-arm64), const IP_MINTTL ideal-int
pkg syscall (freebsd-arm64), const IP_MSFILTER = 74
pkg syscall (freebsd-arm64), const IP_MSFILTER ideal-int
pkg syscall (freebsd-arm64), const IP_MSS = 576

pkg syscall (freebsd-386), const IP_MAX_SOCK_SRC_FILTER ideal-int
pkg syscall (freebsd-386), const IP_MAX_SOURCE_FILTER ideal-int
pkg syscall (freebsd-386), const IP_MF ideal-int
pkg syscall (freebsd-386), const IP_MINTTL ideal-int
pkg syscall (freebsd-386), const IP_MIN_MEMBERSHIPS ideal-int
pkg syscall (freebsd-386), const IP_MSFILTER ideal-int
pkg syscall (freebsd-386), const IP_MSS ideal-int

pkg syscall (freebsd-386), const IP_MAX_SOCK_SRC_FILTER = 128
pkg syscall (freebsd-386), const IP_MAX_SOURCE_FILTER = 1024
pkg syscall (freebsd-386), const IP_MF = 8192
pkg syscall (freebsd-386), const IP_MINTTL = 66
pkg syscall (freebsd-386), const IP_MIN_MEMBERSHIPS = 31
pkg syscall (freebsd-386), const IP_MSFILTER = 74
pkg syscall (freebsd-386), const IP_MSS = 576
pkg syscall (freebsd-386), const IP_MULTICAST_IF = 9

pkg testing, func Testing() bool #52600
pkg testing/slogtest, func TestHandler(slog.Handler, func() []map[string]interface{}) error #56345
pkg unicode, const Version = "15.0.0" #55079
pkg unicode, var Cypro_Minoan *RangeTable #55079
pkg unicode, var Kawi *RangeTable #55079
pkg unicode, var Nag_Mundari *RangeTable #55079
pkg unicode, var Old_Uyghur *RangeTable #55079
pkg unicode, var Tangsa *RangeTable #55079

pkg syscall (freebsd-386-cgo), const IP_MAX_SOCK_SRC_FILTER ideal-int
pkg syscall (freebsd-386-cgo), const IP_MAX_SOURCE_FILTER ideal-int
pkg syscall (freebsd-386-cgo), const IP_MF ideal-int
pkg syscall (freebsd-386-cgo), const IP_MINTTL ideal-int
pkg syscall (freebsd-386-cgo), const IP_MIN_MEMBERSHIPS ideal-int
pkg syscall (freebsd-386-cgo), const IP_MSFILTER ideal-int
pkg syscall (freebsd-386-cgo), const IP_MSS ideal-int