The defaults that will be compiled into a main package
are reported by the command:

{{raw `
	go list -f '{{.DefaultGODEBUG}}' my/main/package
`}}

Only differences from the base Go toolchain defaults are reported.

When testing a package, `//go:debug` lines in the `*_test.go`
files are treated as directives for the test's main package.

(the actual output may differ from what you see here):
</p>

<pre>
$ cat x.go
package main

func main() {
	println(3)
}
$ GOOS=linux GOARCH=amd64 go tool compile -S x.go        # or: go build -gcflags -S x.go
"".main STEXT size=74 args=0x0 locals=0x10
	0x0000 00000 (x.go:3)	TEXT	"".main(SB), $16-0
	0x0000 00000 (x.go:3)	MOVQ	(TLS), CX
	0x0009 00009 (x.go:3)	CMPQ	SP, 16(CX)
	0x000d 00013 (x.go:3)	JLS	67

Earlier versions of Go did not collect unstopped `Timer`s until after
they had fired and never collected unstopped `Ticker`s.

Second, the timer channel associated with a `Timer` or `Ticker` is
now unbuffered, with capacity 0.
The main effect of this change is that Go now guarantees
that for any call to a `Reset` or `Stop` method, no stale values
prepared before that call will be sent or received after the call.

<p>
A complete program is created by linking a single, unimported package
called the <i>main package</i> with all the packages it imports, transitively.
The main package must
have package name <code>main</code> and
declare a function <code>main</code> that takes no
arguments and returns no value.
</p>

<pre>
func main() { … }
</pre>

<p>

// license that can be found in the LICENSE file.

// This package computes the exported API of a set of Go packages.
// It is only a test, not a command, nor a usefully importable package.

package main

import (
	"bufio"
	"bytes"
	"encoding/json"
	"fmt"
	"go/ast"
	"go/build"
	"go/parser"
	"go/token"
	"go/types"
	"internal/testenv"
	"io"
	"log"
	"os"
	"os/exec"
	"path/filepath"

<code>q</code>'s <code>init</code> functions happens before the start of any of <code>p</code>'s.
</p>

<p class="rule">
The completion of all <code>init</code> functions is synchronized before
the start of the function <code>main.main</code>.
</p>

<h3 id="go">Goroutine creation</h3>

<p class="rule">
The <code>go</code> statement that starts a new goroutine
is synchronized before the start of the goroutine's execution.
</p>

		*targetAddr = *target
	case target.Type == obj.TYPE_MEM && (target.Name == obj.NAME_EXTERN || target.Name == obj.NAME_STATIC):
		// JMP main·morestack(SB)
		*targetAddr = *target
	case target.Type == obj.TYPE_INDIR && (target.Name == obj.NAME_EXTERN || target.Name == obj.NAME_STATIC):
		// JMP *main·morestack(SB)
		*targetAddr = *target
		targetAddr.Type = obj.TYPE_INDIR