be inefficient for allocating only small amounts of small Go values. They're
best used in bulk, on the order of MiB of memory allocated on each use.

Note that by allowing for this limited form of manual memory allocation
that use-after-free bugs are possible with regular Go values. This package
limits the impact of these use-after-free bugs by preventing reuse of freed

	"Path": "/ref/spec"
}-->

<h2 id="Introduction">Introduction</h2>

<p>
This is the reference manual for the Go programming language as it was for
language version 1.17, in October 2021, before the introduction of generics.
It is provided for historical interest.
The current reference manual can be found <a href="/doc/go_spec.html">here</a>.
For more information and other documents, see <a href="/">go.dev</a>.
</p>

to a gcc-compiled function that can be called early during program
startup, and _cgo_thread_start to a gcc-compiled function that can be
used to create a new thread, in place of the runtime's usual direct
system calls.

Internal and External Linking

The text above describes "internal" linking, in which cmd/link parses and
links host object files (ELF, Mach-O, PE, and so on) into the final

	if in.peek {
		in.peek = false
		tok := in.peekToken
		in.text = in.peekText
		return tok
	}
	// If we cannot generate a token after 100 macro invocations, we're in trouble.
	// The usual case is caught by Push, below, but be safe.
	for nesting := 0; nesting < 100; {
		tok := in.Stack.Next()
		switch tok {
		case '#':
			if !in.beginningOfLine {
				in.Error("'#' must be first item on line")
			}

// The panic built-in function stops normal execution of the current
// goroutine. When a function F calls panic, normal execution of F stops
// immediately. Any functions whose execution was deferred by F are run in
// the usual way, and then F returns to its caller. To the caller G, the
// invocation of F then behaves like a call to panic, terminating G's
// execution and running any deferred functions. This continues until all

// For ARM, only R0 through R15 may appear.
// For ARM64, V0 through V31 with arrangement may appear.
//
// For 386/AMD64 register list specifies 4VNNIW-style multi-source operand.
// For range of 4 elements, Intel manual uses "+3" notation, for example:
//
//	VP4DPWSSDS zmm1{k1}{z}, zmm2+3, m128
//
// Given asm line:
//
//	VP4DPWSSDS Z5, [Z10-Z13], (AX)
//

<!--{
	"Title": "The Go Programming Language Specification",
	"Subtitle": "Language version go1.22 (April 25, 2024)",
	"Path": "/ref/spec"
}-->

<h2 id="Introduction">Introduction</h2>

<p>
This is the reference manual for the Go programming language.
The pre-Go1.18 version, without generics, can be found
<a href="/doc/go1.17_spec.html">here</a>.
For more information and other documents, see <a href="/">go.dev</a>.
</p>

<p>

Go on iOS
=========

To run the standard library tests, run all.bash as usual, but with the compiler
set to the clang wrapper that invokes clang for iOS. For example, this command runs
 all.bash on the iOS emulator:

	GOOS=ios GOARCH=amd64 CGO_ENABLED=1 CC_FOR_TARGET=$(pwd)/../misc/ios/clangwrap.sh ./all.bash

If CC_FOR_TARGET is not set when the toolchain is built (make.bash or all.bash), CC
can be set on the command line. For example,

			case 1:
				tr = NewReader(&reader{strings.NewReader(v.input)})
				s1, s2 = "io.Reader", "manual"
			case 2:
				tr = NewReader(&readSeeker{strings.NewReader(v.input)})
				s1, s2 = "io.ReadSeeker", "auto"
			case 3:
				tr = NewReader(&readSeeker{strings.NewReader(v.input)})
				s1, s2 = "io.ReadSeeker", "manual"
			case 4:
				tr = NewReader(&readBadSeeker{strings.NewReader(v.input)})

		return true
	}
	return false
}

// ARMMRCOffset implements the peculiar encoding of the MRC and MCR instructions.
// The difference between MRC and MCR is represented by a bit high in the word, not
// in the usual way by the opcode itself. Asm must use AMRC for both instructions, so
// we return the opcode for MRC so that asm doesn't need to import obj/arm.