attempts = max
			}
		}
	}

	if os.Getenv("test18146") == "exec" {
		runtime.GOMAXPROCS(1)
		for n := threads; n > 0; n-- {
			go func() {
				for {
					_ = md5.Sum([]byte("Hello, !"))
				}
			}()
		}
		runtime.GOMAXPROCS(threads)
		argv := append(os.Args, "-test.run=^$")
		if err := syscall.Exec(os.Args[0], argv, os.Environ()); err != nil {
			t.Fatal(err)
		}
	}

# The environment overrides everything else.

# Use the Go module mirror and checksum database by default.
# See https://proxy.golang.org for details.
GOPROXY=https://proxy.golang.org,direct
GOSUMDB=sum.golang.org

# Automatically download newer toolchains as directed by go.mod files.
# See https://go.dev/doc/toolchain for details.

pkg runtime/debug, type Module struct
pkg runtime/debug, type Module struct, Path string
pkg runtime/debug, type Module struct, Replace *Module
pkg runtime/debug, type Module struct, Sum string
pkg runtime/debug, type Module struct, Version string
pkg strings, func ReplaceAll(string, string, string) string
pkg strings, method (*Builder) Cap() int
pkg syscall (freebsd-386), const S_IRWXG = 56

distinct arrays always represent distinct storage.
</p>
<p>
The array underlying a slice may extend past the end of the slice.
The <i>capacity</i> is a measure of that extent: it is the sum of
the length of the slice and the length of the array beyond the slice;
a slice of length up to that capacity can be created by
<a href="#Slice_expressions"><i>slicing</i></a> a new one from the original slice.

        GONOPROXY=""
        GONOSUMDB=""
        GOOS="darwin"
        GOPATH="/Users/gopher/go"
        GOPRIVATE=""
        GOPROXY="https://proxy.golang.org,direct"
        GOROOT="/usr/local/go"
        GOSUMDB="sum.golang.org"
        GOTMPDIR=""
        GOTOOLDIR="/usr/local/go/pkg/tool/darwin_arm64"
        GOVCS=""
        GOVERSION="go1.20.7"
        GCCGO="gccgo"
        AR="ar"
        CC="clang"
        CXX="clang++"

</p>

<pre>
// sum returns the sum (concatenation, for strings) of its arguments.
func sum[T ~int | ~float64 | ~string](x... T) T { … }

x := sum                       // illegal: the type of x is unknown
intSum := sum[int]             // intSum has type func(x... int) int
a := intSum(2, 3)              // a has value 5 of type int
b := sum[float64](2.0, 3)      // b has value 5.0 of type float64

pkg crypto/cipher, type AEAD interface, Overhead() int
pkg crypto/cipher, type AEAD interface, Seal([]uint8, []uint8, []uint8, []uint8) []uint8
pkg crypto/md5, func Sum([]uint8) [16]uint8
pkg crypto/rsa, const PSSSaltLengthAuto = 0
pkg crypto/rsa, const PSSSaltLengthAuto ideal-int
pkg crypto/rsa, const PSSSaltLengthEqualsHash = -1
pkg crypto/rsa, const PSSSaltLengthEqualsHash ideal-int

				t.Fatalf("got %d headers, want %d headers", len(hdrs), len(v.headers))
			}

			for i, sum := range chksums {
				if i >= len(v.chksums) {
					t.Fatalf("entry %d: unexpected sum: got %s", i, sum)
				}
				if sum != v.chksums[i] {
					t.Fatalf("entry %d: incorrect checksum: got %s, want %s", i, sum, v.chksums[i])
				}
			}

			if err != v.err {

	f.formatOctal(field[:7], chksum) // Never fails since 128776 < 262143
	field[7] = ' '
}

// computeChecksum computes the checksum for the header block.
// POSIX specifies a sum of the unsigned byte values, but the Sun tar used
// signed byte values.
// We compute and return both.
func (b *block) computeChecksum() (unsigned, signed int64) {
	for i, c := range b {
		if 148 <= i && i < 156 {

		modPath = parts[2]
		modDir = parts[3]
	}

	return importPath, isStd, modPath, modDir, nil
}

// adbCopyTree copies testdata, go.mod, go.sum files from subdir
// and from parent directories all the way up to the root of subdir.
// go.mod and go.sum files are needed for the go tool modules queries,
// and the testdata directories for tests.  It is common for tests to
// reach out into testdata from parent packages.