}

// dwarfSourceLine tries to get file/line information using DWARF.
// This is for C functions that appear in the profile.
// Returns nil if there is no information available.
func (f *file) dwarfSourceLine(addr uint64) []driver.Frame {
	if f.dwarf == nil && !f.triedDwarf {
		// Ignore any error--we don't care exactly why there
		// is no DWARF info.
		f.dwarf, _ = f.file.DWARF()
		f.triedDwarf = true
	}

	if f.dwarf != nil {

		}
		if t.Align = t.Size; t.Align >= c.ptrSize {
			t.Align = c.ptrSize
		}

	case *dwarf.VoidType:
		t.Go = c.goVoid
		t.C.Set("void")
		t.Align = 1
	}

	switch dtype.(type) {
	case *dwarf.AddrType, *dwarf.BoolType, *dwarf.CharType, *dwarf.ComplexType, *dwarf.IntType, *dwarf.FloatType, *dwarf.UcharType, *dwarf.UintType:
		s := dtype.Common().Name
		if s != "" {
			if ss, ok := dwarfToName[s]; ok {

	}
	return binary.Write(r.f, r.order, data)
}

// machoCombineDwarf merges dwarf info generated by dsymutil into a macho executable.
//
// With internal linking, DWARF is embedded into the executable, this lets us do the
// same for external linking.
// exef is the file of the executable with no DWARF. It must have enough room in the macho
// header to add the DWARF sections. (Use ld's -headerpad option)
// exem is the macho representation of exef.

					list = append(list, dwarf.DW_OP_call_frame_cfa)
				} else {
					list = append(list, dwarf.DW_OP_fbreg)
					list = dwarf.AppendSleb128(list, int64(loc.stackOffsetValue()))
				}
			} else {
				regnum := state.ctxt.Arch.DWARFRegisters[state.registers[firstReg(loc.Registers)].ObjNum()]
				if regnum < 32 {
					list = append(list, dwarf.DW_OP_reg0+byte(regnum))
				} else {

	default:
		return errors.New("applyRelocations: not implemented")
	}
}

// canApplyRelocation reports whether we should try to apply a
// relocation to a DWARF data section, given a pointer to the symbol
// targeted by the relocation.
// Most relocations in DWARF data tend to be section-relative, but
// some target non-section symbols (for example, low_PC attrs on
// subprogram or compilation unit DIEs that target function symbols).

	"cmp",
	"cmd/asm",
	"cmd/asm/internal/...",
	"cmd/cgo",
	"cmd/compile",
	"cmd/compile/internal/...",
	"cmd/internal/archive",
	"cmd/internal/bio",
	"cmd/internal/codesign",
	"cmd/internal/dwarf",
	"cmd/internal/edit",
	"cmd/internal/gcprog",
	"cmd/internal/goobj",
	"cmd/internal/notsha256",
	"cmd/internal/obj/...",
	"cmd/internal/objabi",
	"cmd/internal/pgo",
	"cmd/internal/pkgpath",

	flag.Var(&flagExtld, "extld", "use `linker` when linking in external mode")
	flag.Var(&flagExtldflags, "extldflags", "pass `flags` to external linker")
	flag.Var(&flagW, "w", "disable DWARF generation")
}

// Flags used by the linker. The exported flags are used by the architecture-specific packages.
var (
	flagBuildid = flag.String("buildid", "", "record `id` as Go toolchain build id")

	SMACHOINDIRECTPLT
	SMACHOINDIRECTGOT
	SFILEPATH
	SDYNIMPORT
	SHOSTOBJ
	SUNDEFEXT // Undefined symbol for resolution by external linker

	// Sections for debugging information
	SDWARFSECT
	// DWARF symbol types
	SDWARFCUINFO
	SDWARFCONST
	SDWARFFCN
	SDWARFABSFCN
	SDWARFTYPE
	SDWARFVAR
	SDWARFRANGE
	SDWARFLOC
	SDWARFLINES

	// SEH symbol types
	SSEHUNWINDINFO
	SSEHSECT
)

		case objabi.R_DWARFSECREF:
			if ldr.SymSect(rs) == nil {
				st.err.Errorf(s, "missing DWARF section for relocation target %s", ldr.SymName(rs))
			}

			if target.IsExternal() {
				// On most platforms, the external linker needs to adjust DWARF references
				// as it combines DWARF sections. However, on Darwin, dsymutil does the
				// DWARF linking, and it understands how to follow section offsets.

	DwFixups           *DwarfFixupTable
	Imports            []goobj.ImportedPkg
	DiagFunc           func(string, ...interface{})
	DiagFlush          func()
	DebugInfo          func(fn *LSym, info *LSym, curfn Func) ([]dwarf.Scope, dwarf.InlCalls)
	GenAbstractFunc    func(fn *LSym)
	Errors             int

	InParallel    bool // parallel backend phase in effect