<a href="#Expressions">expression</a>; it is the most recent value
<a href="#Assignments">assigned</a> to the variable.
If a variable has not yet been assigned a value, its value is the
<a href="#The_zero_value">zero value</a> for its type.
</p>


<h2 id="Types">Types</h2>

<p>
A type determines a set of values together with operations and methods specific

#cgo directives within these comments to tweak the behavior of the C, C++
or Fortran compiler. Values defined in multiple directives are concatenated
together. The directive can include a list of build constraints limiting its
effect to systems satisfying one of the constraints
(see https://golang.org/pkg/go/build/#hdr-Build_Constraints for details about the constraint syntax).
For example:

	// #cgo CFLAGS: -DPNG_DEBUG=1

// value. Unlike new, make's return type is the same as the type of its
// argument, not a pointer to it. The specification of the result depends on
// the type:
//
//	Slice: The size specifies the length. The capacity of the slice is
//	equal to its length. A second integer argument may be provided to
//	specify a different capacity; it must be no smaller than the

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build ignore

// Mkzip writes a zoneinfo.zip with the content of the current directory
// and its subdirectories, with no compression, suitable for package time.
//
// Usage:
//
//	go run ../../mkzip.go ../../zoneinfo.zip
//
// We use this program instead of 'zip -0 -r ../../zoneinfo.zip *' to get

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,
then fixing the bug will break that code.
New features can also have similar impacts:

  x.go:3		0x1050203		e83882ffff		CALL runtime.morestack_noctxt(SB)
  x.go:3		0x1050208		ebb6			JMP main.main(SB)
</pre>

<h3 id="constants">Constants</h3>

<p>
Although the assembler takes its guidance from the Plan 9 assemblers,
it is a distinct program, so there are some differences.
One is in constant evaluation.
Constant expressions in the assembler are parsed using Go's operator

The new [GODEBUG setting](/doc/godebug) [`asynctimerchan=1`](/pkg/time/#NewTimer)
can be used to revert back to asynchronous channel behaviors

<a href="#Expressions">expression</a>; it is the most recent value
<a href="#Assignment_statements">assigned</a> to the variable.
If a variable has not yet been assigned a value, its value is the
<a href="#The_zero_value">zero value</a> for its type.
</p>


<h2 id="Types">Types</h2>

<p>
A type determines a set of values together with operations and methods specific

The [Alias] type now has an [Rhs] method that returns the type on the
right-hand side of its declaration: given `type A = B`, the `Rhs` of A

The [SetCrashOutput] function allows the user to specify an alternate
file to which the runtime should write its fatal crash report.
It may be used to construct an automated reporting mechanism for all
unexpected crashes, not just those in goroutines that explicitly use