fmt.Fprintf(&buf, "\t"+`.section .go.buildid,"e"`+"\n")
	} else if cfg.Goarch == "sparc" || cfg.Goarch == "sparc64" {
		fmt.Fprintf(&buf, "\t"+`.section ".go.buildid",#exclude`+"\n")
	} else { // cfg.Goarch == "386" || cfg.Goarch == "amd64"
		fmt.Fprintf(&buf, "\t"+`.section .go.buildid,#exclude`+"\n")
	}
	fmt.Fprintf(&buf, "\t.byte ")
	for i := 0; i < len(a.buildID); i++ {
		if i > 0 {
			if i%8 == 0 {

	gcBgMarkWorkerCount int32

	// Information about what cpu features are available.
	// Packages outside the runtime should not use these
	// as they are not an external api.
	// Set on startup in asm_{386,amd64}.s
	processorVersionInfo uint32
	isIntel              bool
)

// set by cmd/link on arm systems
// accessed using linkname by internal/runtime/atomic.
//
// goarm should be an internal detail,

	// Use a deadline to try to get some output even if the program hangs.
	ctx := context.Background()
	if deadline, ok := t.Deadline(); ok {
		// Leave a 20% grace period to flush output, which may be large on the
		// linux/386 builders because we're running the subprocess under strace.
		deadline = deadline.Add(-time.Until(deadline) / 5)

		var cancel context.CancelFunc
		ctx, cancel = context.WithDeadline(ctx, deadline)
		defer cancel()
	}

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
	// #cgo amd64 386 CFLAGS: -DX86=1
	// #cgo LDFLAGS: -lpng
	// #include <png.h>
	import "C"

Alternatively, CPPFLAGS and LDFLAGS may be obtained via the pkg-config tool
using a '#cgo pkg-config:' directive followed by the package names.