n = debug.tracebackancestors
	}
	ancestors := make([]ancestorInfo, n)
	copy(ancestors[1:], callerAncestors)

	var pcs [tracebackInnerFrames]uintptr
	npcs := gcallers(callergp, 0, pcs[:])
	ipcs := make([]uintptr, npcs)
	copy(ipcs, pcs[:])
	ancestors[0] = ancestorInfo{
		pcs:  ipcs,
		goid: callergp.goid,
		gopc: callergp.gopc,
	}

	ancestorsp := new([]ancestorInfo)
	*ancestorsp = ancestors

	data = append(data, s...)
	return data
}

// assign addresses to text
func (ctxt *Link) textaddress() {
	addsection(ctxt.loader, ctxt.Arch, &Segtext, ".text", 05)

	// Assign PCs in text segment.
	// Could parallelize, by assigning to text
	// and then letting threads copy down, but probably not worth it.
	sect := Segtext.Sections[0]

	sect.Align = int32(Funcalign)

	for _, jt := range cursym.Func().JumpTables {
		for i, p := range jt.Targets {
			// The ith jumptable entry points to the p.Pc'th
			// byte in the function symbol s.
			// TODO: try using relative PCs.
			jt.Sym.WriteAddr(ctxt, int64(i)*8, 8, cursym, p.Pc)
		}
	}
}

// isUnsafePoint returns whether p is an unsafe point.
func (c *ctxt7) isUnsafePoint(p *obj.Prog) bool {