profile](/pkg/runtime/pprof#Profile). Contention on these locks is always
reported at `runtime._LostContendedRuntimeLock`. Complete stack traces of
runtime locks can be enabled with the [`runtimecontentionstacks`
setting](/pkg/runtime#hdr-Environment_Variable). These stack traces have
non-standard semantics, see setting documentation for details.

	BCL 20,undefined_symbol,CTR     // BCL $20,CR0LT,CTR // 4e800421
	BCL 20,undefined_symbol+1,CTR   // BCL $20,CR0GT,CTR // 4e810421

	// Verify bc encoding (without pic enabled)
	BC $16,CR0LT,0(PC)              // 42000000
	BCL $16,CR0LT,0(PC)             // 42000001
	BC $18,CR0LT,0(PC)              // 42400000

	MOVD SPR(3), 4(R1)              // 7fe302a6fbe10004

	    and a signed binary exponent of at least 16 bits.</li>

	<li>Give an error if unable to represent an integer constant
	    precisely.</li>

	<li>Give an error if unable to represent a floating-point or
	    complex constant due to overflow.</li>

	<li>Round to the nearest representable constant if unable to
	    represent a floating-point or complex constant due to limits
	    on precision.</li>
</ul>

	export GOARCH=$(echo $target | sed 's/.*-//')
	unset GOARM
	if [ "$GOARCH" = "arm5" ]; then
		export GOARCH=arm
		export GOARM=5
	fi

	# Build and vet everything.
	# cmd/go/internal/work/exec.go enables the same vet flags during go test of std cmd
	# and should be kept in sync with any vet flag changes here.
	if ! "$GOROOT/bin/go" build std cmd || ! "$GOROOT/bin/go" vet -unsafeptr=false std cmd; then
		failed=true