lower-case letter. Exception: static variables in the preamble may
not be referenced from Go code; static functions are permitted.

See $GOROOT/cmd/cgo/internal/teststdio and $GOROOT/misc/cgo/gmp for examples. See
"C? Go? Cgo!" for an introduction to using cgo:
https://golang.org/doc/articles/c_go_cgo.html.

CFLAGS, CPPFLAGS, CXXFLAGS, FFLAGS and LDFLAGS may be defined with pseudo
#cgo directives within these comments to tweak the behavior of the C, C++

<!--{
	"Title": "The Go Programming Language Specification",
	"Subtitle": "Version of Oct 15, 2021",
	"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>.

<!--{
	"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>

set fixed-width phrases with non-fixed-width spaces, as in
`hello` `world`.
-->

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  main ul li { margin: 0.5em 0; }
</style>

set fixed-width phrases with non-fixed-width spaces, as in
`hello` `world`.
-->

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layout: article
---

<!--
This document is kept in the Go repo, not x/website,
because it documents the full list of known GODEBUG settings,
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,

<!--{
	"Title": "A Quick Guide to Go's Assembler",
	"Path":  "/doc/asm"
}-->

<h2 id="introduction">A Quick Guide to Go's Assembler</h2>

<p>
This document is a quick outline of the unusual form of assembly language used by the <code>gc</code> Go compiler.
The document is not comprehensive.
</p>

<p>
The assembler is based on the input style of the Plan 9 assemblers, which is documented in detail

<!--{
	"Title": "The Go Memory Model",
	"Subtitle": "Version of June 6, 2022",
	"Path": "/ref/mem"
}-->

<style>
p.rule {
  font-style: italic;
}
</style>

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

<p>
The Go memory model specifies the conditions under which
reads of a variable in one goroutine can be guaranteed to
observe values produced by writes to the same variable in a different goroutine.
</p>

<code>hello</code> <code>world</code>.
Do not send CLs removing the interior tags from such phrases.
-->

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  main ul li { margin: 0.5em 0; }
</style>

<h2 id="introduction">DRAFT RELEASE NOTES — Introduction to Go 1.22</h2>

<p>
  <strong>
    Go 1.22 is not yet released. These are work-in-progress
    release notes. Go 1.22 is expected to be released in February 2024.
  </strong>
</p>