if off+strLen > int64(len(sb.data)) {
		panic("attempt to write past end of buffer")
	}
	copy(sb.data[off:off+strLen], str)
	return off + strLen
}

// AddCStringAt adds str plus a null terminating byte.
func (sb *SymbolBuilder) AddCStringAt(off int64, str string) int64 {
	strLen := int64(len(str))
	if off+strLen+1 > int64(len(sb.data)) {
		panic("attempt to write past end of buffer")
	}

	// Write the null terminated strings.
	writeFuncNameTab := func(ctxt *Link, s loader.Sym) {
		symtab := ctxt.loader.MakeSymbolUpdater(s)
		for s, off := range nameOffsets {
			symtab.AddCStringAt(int64(off), ctxt.loader.SymName(s))
		}
	}

	// Loop through the CUs, and calculate the size needed.
	var size int64
	walkFuncs(ctxt, funcs, func(s loader.Sym) {
		nameOffsets[s] = uint32(size)