// should never return
	CALL	runtime·abort(SB)
	UNDEF

/*
 * support for morestack
 */

// Called during function prolog when more stack is needed.
// Caller has already loaded:
// R3: framesize, R4: argsize, R5: LR
//
// The traceback routines see morestack on a g0 as being
// the top of a stack (for example, morestack calling newstack
// calling the scheduler calling newm calling gc), so we must

	// should never return
	CALL	runtime·abort(SB)
	UNDEF

/*
 * support for morestack
 */

// Called during function prolog when more stack is needed.
// Caller has already loaded:
// R3 prolog's LR (R30)
//
// The traceback routines see morestack on a g0 as being
// the top of a stack (for example, morestack calling newstack
// calling the scheduler calling newm calling gc), so we must

// these functions, which is in
// cmd/compile/internal/devirtualize/pgo.maybeDevirtualizeFunctionCall.
func getclosureptr() uintptr

//go:noescape
func asmcgocall(fn, arg unsafe.Pointer) int32

func morestack()

// morestack_noctxt should be an internal detail,
// but widely used packages access it using linkname.
// Notable members of the hall of shame include:
//   - github.com/cloudwego/frugal
//

			}
			got := runTestProg(t, prog, test)
			t.Log(got)
			want := "SIGSEGV"
			if !strings.Contains(got, want) {
				if runtime.GOOS == "darwin" && runtime.GOARCH == "amd64" && strings.Contains(got, "fatal: morestack on g0") {
					testenv.SkipFlaky(t, 39457)
				}
				t.Errorf("did not see %q in output", want)
			}

			// No runtime errors like "runtime: unknown pc".
			switch runtime.GOOS {

		cmd.Env = append(cmd.Env, "TEST_G0_STACK_OVERFLOW=1")
		out, err := cmd.CombinedOutput()
		t.Logf("output:\n%s", out)
		// Don't check err since it's expected to crash.
		if n := strings.Count(string(out), "morestack on g0\n"); n != 1 {
			t.Fatalf("%s\n(exit status %v)", out, err)
		}
		if runtime.CrashStackImplemented {
			// check for a stack trace
			want := "runtime.stackOverflow"

		if u.flags&unwindJumpStack != 0 && gp == gp.m.g0 && gp.m.curg != nil && gp.m.curg.m == gp.m {
			switch f.funcID {
			case abi.FuncID_morestack:
				// morestack does not return normally -- newstack()
				// gogo's to curg.sched. Match that.
				// This keeps morestack() from showing up in the backtrace,
				// but that makes some sense since it'll never be returned
				// to.
				gp = gp.m.curg
				u.g.set(gp)

		next++
	}

	// Issue an error if we see a function defined as ABIInternal
	// without NOSPLIT. In ABIInternal, obj needs to know the function
	// signature in order to construct the morestack path, so this
	// currently isn't supported for asm functions.
	if nameAddr.Sym.ABI() == obj.ABIInternal && flag&obj.NOSPLIT == 0 {
		p.errorf("TEXT %q: ABIInternal requires NOSPLIT", name)
	}

}

//go:nosplit
//go:nowritebarrierrec
func badmorestackg0() {
	if !crashStackImplemented {
		writeErrStr("fatal: morestack on g0\n")
		return
	}

	g := getg()
	switchToCrashStack(func() {
		print("runtime: morestack on g0, stack [", hex(g.stack.lo), " ", hex(g.stack.hi), "], sp=", hex(g.sched.sp), ", called from\n")
		g.m.traceback = 2 // include pc and sp in stack trace

		// one of the following holds for a function F with pointer-valued register arg X:
		//  0. No GC (so an uninitialized spill slot is okay)
		//  1. GC at entry of F.  GC is precise, but the spills around morestack initialize X's spill slot
		//  2. Stack growth at entry of F.  Same as GC.
		//  3. GC occurs within F itself.  This has to be from preemption, and thus GC is conservative.

			&goTest{
				variant: "runtime:gcstoptheworld2",
				timeout: 300 * time.Second,
				short:   true,
				env:     []string{"GODEBUG=gcstoptheworld=2"},
				pkg:     "archive/zip",
			})
	}

	// morestack tests. We only run these in long-test mode
	// (with GO_TEST_SHORT=0) because the runtime test is
	// already quite long and mayMoreStackMove makes it about
	// twice as slow.
	if !t.compileOnly && !t.short {