diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 9c899443..71bf277b 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -33,10 +33,14 @@ jobs:
           restore-keys: ${{ runner.os }}-protocompile-ci-
       - name: Test
         run: make test
+      - name: Benchmarks
+        # no need to run benchmarks for every Go version
+        if: matrix.go-version == '1.19.x'
+        run: make benchmarks
       - name: Lint
         # Often, lint & gofmt guidelines depend on the Go version. To prevent
         # conflicting guidance, run only on the most recent supported version.
         # For the same reason, only check generated code on the most recent
         # supported version.
         if: matrix.go-version == '1.19.x'
-        run: make checkgenerate && make lint
+        run: make checkgenerate lint
diff --git a/.golangci.yml b/.golangci.yml
index 006366b1..8ec8d758 100644
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -85,3 +85,8 @@ issues:
     # Don't ban use of fmt.Errorf to create new errors, but the remaining
     # checks from err113 are useful.
     - "err113: do not define dynamic errors.*"
+  exclude-rules:
+    # Benchmarks can't be run in parallel
+    - path: benchmark_test\.go
+      linters:
+        - paralleltest
\ No newline at end of file
diff --git a/Makefile b/Makefile
index cf98def8..47d87c7d 100644
--- a/Makefile
+++ b/Makefile
@@ -15,6 +15,7 @@ TOOLS_MOD_DIR := ./internal/tools
 UNAME_OS := $(shell uname -s)
 UNAME_ARCH := $(shell uname -m)
 
+# NB: this must be kept in sync with constant in internal/benchmarks.
 PROTOC_VERSION ?= 21.7
 PROTOC_DIR := $(abspath ./internal/testdata/protoc/$(PROTOC_VERSION))
 PROTOC := $(PROTOC_DIR)/bin/protoc
@@ -50,6 +51,10 @@ clean: ## Delete intermediate build artifacts
 test: build ## Run unit tests
 	$(GO) test -vet=off -race -cover ./...
 
+.PHONY: benchmarks
+benchmarks: build ## Run benchmarks
+	cd internal/benchmarks && $(GO) test -bench=. -benchmem -v ./...
+
 .PHONY: build
 build: generate ## Build all packages
 	$(GO) build ./...
@@ -60,12 +65,14 @@ install: ## Install all binaries
 
 .PHONY: lint
 lint: $(BIN)/golangci-lint ## Lint Go
-	$(GO) vet ./...
+	$(GO) vet ./... ./internal/benchmarks/...
 	$(BIN)/golangci-lint run
+	cd internal/benchmarks && $(BIN)/golangci-lint run
 
 .PHONY: lintfix
 lintfix: $(BIN)/golangci-lint ## Automatically fix some lint errors
 	$(BIN)/golangci-lint run --fix
+	cd internal/benchmarks && $(BIN)/golangci-lint run --fix
 
 .PHONY: generate
 generate: $(BIN)/license-header $(BIN)/goyacc test-descriptors ## Regenerate code and licenses
diff --git a/compiler.go b/compiler.go
index c97b95cd..e188f46d 100644
--- a/compiler.go
+++ b/compiler.go
@@ -80,6 +80,13 @@ type Compiler struct {
 	// concludes. Similarly, if they already have source code info but this flag
 	// is false, existing info will be left in place.
 	SourceInfoMode SourceInfoMode
+
+	// If true, ASTs are retained in compilation results for which an AST was
+	// constructed. So any linker.Result value in the resulting compiled files
+	// will have an AST, in addition to descriptors. If left false, the AST
+	// will be removed as soon as it's no longer needed. This can help reduce
+	// total memory usage for operations involving a large number of files.
+	RetainASTs bool
 }
 
 // SourceInfoMode indicates how source code info is generated by a Compiler.
@@ -518,6 +525,10 @@ func (t *task) link(parseRes parser.Result, deps linker.Files) (linker.File, err
 		}
 		file.PopulateSourceCodeInfo()
 	}
+
+	if !t.e.c.RetainASTs {
+		file.RemoveAST()
+	}
 	return file, nil
 }
 
diff --git a/go.work b/go.work
new file mode 100644
index 00000000..de1c41a8
--- /dev/null
+++ b/go.work
@@ -0,0 +1,7 @@
+go 1.19
+
+use (
+	.
+	./internal/benchmarks
+	./internal/tools
+)
diff --git a/go.work.sum b/go.work.sum
new file mode 100644
index 00000000..8cf92817
--- /dev/null
+++ b/go.work.sum
@@ -0,0 +1,183 @@
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diff --git a/internal/benchmarks/benchmark_test.go b/internal/benchmarks/benchmark_test.go
new file mode 100644
index 00000000..278b9289
--- /dev/null
+++ b/internal/benchmarks/benchmark_test.go
@@ -0,0 +1,524 @@
+// Copyright 2020-2022 Buf Technologies, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package benchmarks
+
+import (
+	"archive/tar"
+	"bytes"
+	"compress/gzip"
+	"context"
+	"fmt"
+	"io"
+	"io/fs"
+	"net/http"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"reflect"
+	"runtime"
+	"sort"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/jhump/protoreflect/desc"
+	"github.com/jhump/protoreflect/desc/protoparse"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/types/descriptorpb"
+
+	"github.com/bufbuild/protocompile"
+	"github.com/bufbuild/protocompile/ast"
+	"github.com/bufbuild/protocompile/linker"
+	"github.com/bufbuild/protocompile/parser"
+	"github.com/bufbuild/protocompile/protoutil"
+	"github.com/bufbuild/protocompile/reporter"
+)
+
+const (
+	// NB: this must be kept in sync with PROTOC_VERSION in Makefile.
+	protocVersion = "21.7"
+
+	googleapisCommit = "cb6fbe8784479b22af38c09a5039d8983e894566"
+)
+
+var (
+	protocPath        = fmt.Sprintf("../testdata/protoc/%s/bin/protoc", protocVersion)
+	googleapisURI     = fmt.Sprintf("https://github.com/googleapis/googleapis/archive/%s.tar.gz", googleapisCommit)
+	googleapisDir     string
+	googleapisSources []string
+)
+
+func TestMain(m *testing.M) {
+	if runtime.GOOS == "windows" {
+		protocPath += ".exe"
+	}
+	if info, err := os.Stat(protocPath); err != nil {
+		if os.IsNotExist(err) {
+			_, _ = fmt.Fprintf(os.Stderr, "Path %s not found. Run `make generate` in the project root first.\n", protocPath)
+		} else {
+			_, _ = fmt.Fprintf(os.Stderr, "Error querying for path %s: %v\n", protocPath, err)
+		}
+		os.Exit(1)
+	} else if info.IsDir() {
+		_, _ = fmt.Fprintf(os.Stderr, "Path %s is a directory but expecting an executable file.\n", protocPath)
+		os.Exit(1)
+	}
+
+	var stat int
+	defer func() {
+		os.Exit(stat)
+	}()
+	// After this point, we can set stat and return instead of directly calling os.Exit.
+	// That allows deferred functions to execute, to perform cleanup, before exiting.
+
+	dir, err := os.MkdirTemp("", "testdownloads")
+	if err != nil {
+		_, _ = fmt.Fprintf(os.Stderr, "Could not create temporary directory: %v\n", err)
+		stat = 1
+		return
+	}
+	defer func() {
+		if err := os.RemoveAll(dir); err != nil {
+			_, _ = fmt.Fprintf(os.Stderr, "Failed to cleanup temp directory %s: %v\n", dir, err)
+		}
+	}()
+
+	if err := downloadAndExpand(googleapisURI, dir); err != nil {
+		_, _ = fmt.Fprintf(os.Stderr, "Failed to download and expand googleapis: %v\n", err)
+		stat = 1
+		return
+	}
+
+	googleapisDir = filepath.Join(dir, fmt.Sprintf("googleapis-%s", googleapisCommit)) + "/"
+	var sourceSize int64
+	err = filepath.Walk(googleapisDir, func(path string, info fs.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if !info.IsDir() && strings.HasSuffix(path, ".proto") {
+			relPath := strings.TrimPrefix(path, googleapisDir)
+			googleapisSources = append(googleapisSources, relPath)
+			sourceSize += info.Size()
+		}
+		return nil
+	})
+	if err != nil {
+		_, _ = fmt.Fprintf(os.Stderr, "Failed to enumerate googleapis source files: %v\n", err)
+		stat = 1
+		return
+	}
+	sort.Strings(googleapisSources)
+	fmt.Printf("%d total source files found in googleapis (%d bytes).\n", len(googleapisSources), sourceSize)
+
+	stat = m.Run()
+}
+
+func downloadAndExpand(url, targetDir string) (e error) {
+	start := time.Now()
+	req, err := http.NewRequestWithContext(context.Background(), http.MethodGet, url, nil)
+	if err != nil {
+		return err
+	}
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return err
+	}
+	if resp.Body != nil {
+		defer func() {
+			if err = resp.Body.Close(); err != nil && e == nil {
+				e = err
+			}
+		}()
+	}
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("downloading %s resulted in status code %s", url, resp.Status)
+	}
+	if err := os.MkdirAll(targetDir, 0777); err != nil {
+		return err
+	}
+	f, err := os.CreateTemp(targetDir, "testdownload.*.tar.gz")
+	if err != nil {
+		return err
+	}
+	defer func() {
+		if f != nil {
+			if err := f.Close(); err != nil {
+				_, _ = fmt.Fprintf(os.Stderr, "warning: failed to close %s: %v\n", f.Name(), err)
+			}
+		}
+	}()
+	n, err := io.Copy(f, resp.Body)
+	if err != nil {
+		return err
+	}
+	fmt.Printf("Downloaded %v; %d bytes (%v).\n", url, n, time.Since(start))
+	archiveName := f.Name()
+	if err := f.Close(); err != nil {
+		_, _ = fmt.Fprintf(os.Stderr, "warning: failed to close %s: %v\n", f.Name(), err)
+	}
+	f = nil
+
+	f, err = os.OpenFile(archiveName, os.O_RDONLY, 0)
+	if err != nil {
+		return err
+	}
+
+	gzr, err := gzip.NewReader(f)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		if err = gzr.Close(); err != nil && e == nil {
+			e = err
+		}
+	}()
+
+	tr := tar.NewReader(gzr)
+	count := 0
+	for {
+		hdr, err := tr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return err
+		}
+		if hdr == nil {
+			continue
+		}
+		target := filepath.Join(targetDir, hdr.Name)
+		switch hdr.Typeflag {
+		case tar.TypeDir:
+			if err := os.MkdirAll(target, 0777); err != nil {
+				return err
+			}
+		case tar.TypeReg:
+			f, err := os.OpenFile(target, os.O_WRONLY|os.O_CREATE|os.O_EXCL, os.FileMode(hdr.Mode))
+			if err != nil {
+				return err
+			}
+			if _, err := io.Copy(f, tr); err != nil {
+				return err
+			}
+			count++
+		default:
+			// skip anything else
+		}
+	}
+	fmt.Printf("Expanded archive into %d files.\n", count)
+
+	return nil
+}
+
+func BenchmarkGoogleapisProtocompile(b *testing.B) {
+	benchmarkGoogleapisProtocompile(b, false, func() *protocompile.Compiler {
+		return &protocompile.Compiler{
+			Resolver: protocompile.WithStandardImports(&protocompile.SourceResolver{
+				ImportPaths: []string{googleapisDir},
+			}),
+			SourceInfoMode: protocompile.SourceInfoExtraComments,
+			// leave MaxParallelism unset to let it use all cores available
+		}
+	})
+}
+
+func BenchmarkGoogleapisProtocompileCanonical(b *testing.B) {
+	benchmarkGoogleapisProtocompile(b, true, func() *protocompile.Compiler {
+		return &protocompile.Compiler{
+			Resolver: protocompile.WithStandardImports(&protocompile.SourceResolver{
+				ImportPaths: []string{googleapisDir},
+			}),
+			SourceInfoMode: protocompile.SourceInfoStandard,
+			// leave MaxParallelism unset to let it use all cores available
+		}
+	})
+}
+
+func BenchmarkGoogleapisProtocompileNoSourceInfo(b *testing.B) {
+	benchmarkGoogleapisProtocompile(b, false, func() *protocompile.Compiler {
+		return &protocompile.Compiler{
+			Resolver: protocompile.WithStandardImports(&protocompile.SourceResolver{
+				ImportPaths: []string{googleapisDir},
+			}),
+			SourceInfoMode: protocompile.SourceInfoNone,
+			// leave MaxParallelism unset to let it use all cores available
+		}
+	})
+}
+
+func benchmarkGoogleapisProtocompile(b *testing.B, canonicalBytes bool, factory func() *protocompile.Compiler) {
+	for i := 0; i < b.N; i++ {
+		benchmarkProtocompile(b, factory(), googleapisSources, canonicalBytes)
+	}
+}
+
+func benchmarkProtocompile(b *testing.B, c *protocompile.Compiler, sources []string, canonicalBytes bool) {
+	fds, err := c.Compile(context.Background(), sources...)
+	require.NoError(b, err)
+	var fdSet descriptorpb.FileDescriptorSet
+	fdSet.File = make([]*descriptorpb.FileDescriptorProto, len(fds))
+	for i, fd := range fds {
+		if canonicalBytes {
+			fdSet.File[i] = fd.(linker.Result).CanonicalProto()
+		} else {
+			fdSet.File[i] = protoutil.ProtoFromFileDescriptor(fd)
+		}
+	}
+	// protoc is writing output to file descriptor set, so we should, too
+	writeToNull(b, &fdSet)
+}
+
+func BenchmarkGoogleapisProtoparse(b *testing.B) {
+	benchmarkGoogleapisProtoparse(b, func() *protoparse.Parser {
+		return &protoparse.Parser{
+			ImportPaths:           []string{googleapisDir},
+			IncludeSourceCodeInfo: true,
+		}
+	})
+}
+
+func BenchmarkGoogleapisProtoparseNoSourceInfo(b *testing.B) {
+	benchmarkGoogleapisProtoparse(b, func() *protoparse.Parser {
+		return &protoparse.Parser{
+			ImportPaths:           []string{googleapisDir},
+			IncludeSourceCodeInfo: false,
+		}
+	})
+}
+
+func benchmarkGoogleapisProtoparse(b *testing.B, factory func() *protoparse.Parser) {
+	par := runtime.GOMAXPROCS(-1)
+	cpus := runtime.NumCPU()
+	if par > cpus {
+		par = cpus
+	}
+	for i := 0; i < b.N; i++ {
+		// Buf currently batches files into chunks and then runs all chunks in parallel
+		chunks := make([][]string, par)
+		j := 0
+		total := 0
+		for ch := 0; ch < par; ch++ {
+			chunkStart := j
+			chunkEnd := (ch + 1) * len(googleapisSources) / par
+			chunks[ch] = googleapisSources[chunkStart:chunkEnd]
+			j = chunkEnd
+			total += len(chunks[ch])
+		}
+		require.Equal(b, total, len(googleapisSources))
+		var wg sync.WaitGroup
+		results := make([][]*desc.FileDescriptor, par)
+		errors := make([]error, par)
+		for ch, chunk := range chunks {
+			ch, chunk := ch, chunk
+			wg.Add(1)
+			go func() {
+				defer wg.Done()
+				p := factory()
+				results[ch], errors[ch] = p.ParseFiles(chunk...)
+			}()
+		}
+		wg.Wait()
+		for _, err := range errors {
+			require.NoError(b, err)
+		}
+		var fdSet descriptorpb.FileDescriptorSet
+		fdSet.File = make([]*descriptorpb.FileDescriptorProto, 0, len(googleapisSources))
+		for _, chunk := range results {
+			for _, fd := range chunk {
+				fdSet.File = append(fdSet.File, fd.AsFileDescriptorProto())
+			}
+		}
+		writeToNull(b, &fdSet)
+	}
+}
+
+func BenchmarkGoogleapisProtoc(b *testing.B) {
+	benchmarkGoogleapisProtoc(b, "--include_source_info")
+}
+
+func BenchmarkGoogleapisProtocNoSourceInfo(b *testing.B) {
+	benchmarkGoogleapisProtoc(b)
+}
+
+func benchmarkGoogleapisProtoc(b *testing.B, extraArgs ...string) {
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			args := make([]string, 0, len(googleapisSources)+5)
+			args = append(args, "-I", googleapisDir, "-o", os.DevNull)
+			args = append(args, extraArgs...)
+			args = append(args, googleapisSources...)
+			cmd := exec.Command(protocPath, args...)
+			cmd.Stdin = nil
+			cmd.Stdout = nil
+			var errBuffer bytes.Buffer
+			cmd.Stderr = &errBuffer
+
+			err := cmd.Run()
+			if err != nil {
+				_, _ = os.Stderr.Write(errBuffer.Bytes())
+				b.Fatalf("failed to invoke protoc: %v", err)
+			}
+		}
+	})
+}
+
+func BenchmarkGoogleapisProtocompileSingleThreaded(b *testing.B) {
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			c := &protocompile.Compiler{
+				Resolver: protocompile.WithStandardImports(&protocompile.SourceResolver{
+					ImportPaths: []string{googleapisDir},
+				}),
+				SourceInfoMode: protocompile.SourceInfoExtraComments,
+				// to really test performance compared to protoc and protoparse, we
+				// need to run a single-threaded compile
+				MaxParallelism: 1,
+			}
+			benchmarkProtocompile(b, c, googleapisSources, false)
+		}
+	})
+}
+
+func BenchmarkGoogleapisProtoparseSingleThreaded(b *testing.B) {
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			p := protoparse.Parser{
+				ImportPaths:           []string{googleapisDir},
+				IncludeSourceCodeInfo: true,
+			}
+			fds, err := p.ParseFiles(googleapisSources...)
+			require.NoError(b, err)
+			var fdSet descriptorpb.FileDescriptorSet
+			fdSet.File = make([]*descriptorpb.FileDescriptorProto, len(fds))
+			for i, fd := range fds {
+				fdSet.File[i] = fd.AsFileDescriptorProto()
+			}
+			writeToNull(b, &fdSet)
+		}
+	})
+}
+
+func writeToNull(b *testing.B, fds *descriptorpb.FileDescriptorSet) {
+	f, err := os.OpenFile(os.DevNull, os.O_WRONLY, 0)
+	if err != nil {
+		b.Fatalf("failed to open output file %s: %v", os.DevNull, err)
+	}
+	defer func() {
+		if err := f.Close(); err != nil {
+			_, _ = fmt.Fprintf(os.Stderr, "warning: failed to close %s: %v\n", f.Name(), err)
+		}
+	}()
+	data, err := proto.Marshal(fds)
+	if err != nil {
+		b.Fatalf("failed to marshal file descriptor set: %v", err)
+	}
+	_, err = f.Write(data)
+	if err != nil {
+		b.Fatalf("failed to write file descriptor set to file: %v", err)
+	}
+}
+
+func TestGoogleapisProtocompileResultMemory(t *testing.T) {
+	c := protocompile.Compiler{
+		Resolver: protocompile.WithStandardImports(&protocompile.SourceResolver{
+			ImportPaths: []string{googleapisDir},
+		}),
+		SourceInfoMode: protocompile.SourceInfoExtraComments,
+	}
+	fds, err := c.Compile(context.Background(), googleapisSources...)
+	require.NoError(t, err)
+	measure(t, fds)
+}
+
+func TestGoogleapisProtocompileResultMemoryNoSourceInfo(t *testing.T) {
+	c := protocompile.Compiler{
+		Resolver: protocompile.WithStandardImports(&protocompile.SourceResolver{
+			ImportPaths: []string{googleapisDir},
+		}),
+		SourceInfoMode: protocompile.SourceInfoNone,
+	}
+	fds, err := c.Compile(context.Background(), googleapisSources...)
+	require.NoError(t, err)
+	measure(t, fds)
+}
+
+func TestGoogleapisProtocompileASTMemory(t *testing.T) {
+	var asts []*ast.FileNode
+	for _, file := range googleapisSources {
+		func() {
+			f, err := os.OpenFile(filepath.Join(googleapisDir, file), os.O_RDONLY, 0)
+			require.NoError(t, err)
+			defer func() {
+				if err := f.Close(); err != nil {
+					_, _ = fmt.Fprintf(os.Stderr, "warning: failed to close %s: %v\n", f.Name(), err)
+				}
+			}()
+			h := reporter.NewHandler(nil)
+			ast, err := parser.Parse(file, f, h)
+			require.NoError(t, err)
+			asts = append(asts, ast)
+		}()
+	}
+	measure(t, asts)
+}
+
+func TestGoogleapisProtoparseResultMemory(t *testing.T) {
+	p := protoparse.Parser{
+		ImportPaths:           []string{googleapisDir},
+		IncludeSourceCodeInfo: true,
+	}
+	fds, err := p.ParseFiles(googleapisSources...)
+	require.NoError(t, err)
+	measure(t, fds)
+}
+
+func TestGoogleapisProtoparseResultMemoryNoSourceInfo(t *testing.T) {
+	p := protoparse.Parser{
+		ImportPaths:           []string{googleapisDir},
+		IncludeSourceCodeInfo: false,
+	}
+	fds, err := p.ParseFiles(googleapisSources...)
+	require.NoError(t, err)
+	measure(t, fds)
+}
+
+func TestGoogleapisProtoparseASTMemory(t *testing.T) {
+	p := protoparse.Parser{
+		IncludeSourceCodeInfo: true,
+	}
+	// NB: ParseToAST fails to respect import paths, so we have to pass full names
+	filenames := make([]string, len(googleapisSources))
+	for i := range googleapisSources {
+		filenames[i] = filepath.Join(googleapisDir, googleapisSources[i])
+	}
+	asts, err := p.ParseToAST(filenames...)
+	require.NoError(t, err)
+	measure(t, asts)
+}
+
+func measure(t *testing.T, v any) {
+	// log heap allocations
+	runtime.GC()
+	var m runtime.MemStats
+	runtime.ReadMemStats(&m)
+	t.Logf("(heap used: %d bytes)", m.Alloc)
+
+	// and then try to directly measure just the given value
+	mt := newMeasuringTape()
+	mt.measure(reflect.ValueOf(v))
+	t.Logf("memory used: %d bytes", mt.memoryUsed())
+}
diff --git a/internal/benchmarks/go.mod b/internal/benchmarks/go.mod
new file mode 100644
index 00000000..7a6fbbf3
--- /dev/null
+++ b/internal/benchmarks/go.mod
@@ -0,0 +1,21 @@
+module github.com/jhump/protocompile/internal/benchmarks
+
+go 1.19
+
+require (
+	github.com/bufbuild/protocompile v0.0.0-20221004230924-06a336f5b6be
+	github.com/igrmk/treemap/v2 v2.0.1
+	github.com/jhump/protoreflect v1.13.0
+	github.com/stretchr/testify v1.8.0
+	google.golang.org/protobuf v1.28.2-0.20220831092852-f930b1dc76e8
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/golang/protobuf v1.5.0 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	golang.org/x/exp v0.0.0-20220317015231-48e79f11773a // indirect
+	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c // indirect
+	google.golang.org/genproto v0.0.0-20200526211855-cb27e3aa2013 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)
diff --git a/internal/benchmarks/go.sum b/internal/benchmarks/go.sum
new file mode 100644
index 00000000..c2ad6fe6
--- /dev/null
+++ b/internal/benchmarks/go.sum
@@ -0,0 +1,128 @@
+cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
+github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/bufbuild/protocompile v0.0.0-20221004230924-06a336f5b6be h1:nj/vRT4P6Kz2Hr8lvyYe3EgTKfg9fNMJKHaZZXHvt9g=
+github.com/bufbuild/protocompile v0.0.0-20221004230924-06a336f5b6be/go.mod h1:ix/MMMdsT3fzxfw91dvbfzKW3fRRnuPCP47kpAm5m/4=
+github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
+github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
+github.com/cncf/udpa/go v0.0.0-20201120205902-5459f2c99403/go.mod h1:WmhPx2Nbnhtbo57+VJT5O0JRkEi1Wbu0z5j0R8u5Hbk=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/envoyproxy/go-control-plane v0.9.0/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymFceY/DCBVvsKhRF0iEA4=
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+github.com/envoyproxy/go-control-plane v0.9.9-0.20210217033140-668b12f5399d/go.mod h1:cXg6YxExXjJnVBQHBLXeUAgxn2UodCpnH306RInaBQk=
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diff --git a/internal/benchmarks/measure.go b/internal/benchmarks/measure.go
new file mode 100644
index 00000000..c474bd76
--- /dev/null
+++ b/internal/benchmarks/measure.go
@@ -0,0 +1,214 @@
+// Copyright 2020-2022 Buf Technologies, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package benchmarks
+
+import (
+	"math/bits"
+	"reflect"
+	"unsafe"
+
+	"github.com/igrmk/treemap/v2"
+)
+
+type measuringTape struct {
+	bst   *treemap.TreeMap[uintptr, uint64]
+	other uint64
+}
+
+func newMeasuringTape() *measuringTape {
+	return &measuringTape{
+		bst: treemap.New[uintptr, uint64](),
+	}
+}
+
+func (t *measuringTape) insert(start uintptr, length uint64) bool {
+	if start == 0 {
+		// nil ptr
+		return false
+	}
+	end := start + uintptr(length)
+	iter := t.bst.LowerBound(start)
+	if !iter.Valid() {
+		// tree is empty or all entries are too low to overlap
+		t.bst.Set(end, length)
+		return true
+	}
+	entryEnd := iter.Key()
+	entryStart := entryEnd - uintptr(iter.Value())
+	if entryStart > end {
+		// range does not exist; add it
+		t.bst.Set(end, length)
+		return true
+	}
+	if entryStart <= start && entryEnd >= end {
+		// range is entirely encompassed in existing entry
+		return false
+	}
+
+	// navigate back to find the first overlapping range and push
+	// start out if needed to encompass all overlaps
+	first := t.bst.Iterator().Key()
+	for entryStart > start {
+		if iter.Key() == first {
+			// can go no further
+			break
+		}
+		iter.Prev()
+		if iter.Key() < start {
+			// gone back too far
+			break
+		}
+		entryStart = iter.Key() - uintptr(iter.Value())
+	}
+	if entryStart < start {
+		start = entryStart
+	}
+
+	// find last overlapping range
+	if entryEnd < end {
+		for entryEnd < end {
+			// remove overlaps that will be replaced with
+			// new, larger, encompassing range
+			t.bst.Del(entryEnd)
+
+			// Iterator doesn't like concurrent removal of node. So after
+			// Del above, we can't call Next; we have to re-search the tree
+			// for the next node.
+			iter = t.bst.LowerBound(entryEnd)
+			if !iter.Valid() {
+				// can go no further
+				break
+			}
+			st := iter.Key() - uintptr(iter.Value())
+			if st > end {
+				// gone too far
+				break
+			}
+			entryEnd = iter.Key()
+		}
+	}
+	if entryEnd > end {
+		end = entryEnd
+	}
+
+	t.bst.Set(end, uint64(end-start))
+	return true
+}
+
+func (t *measuringTape) memoryUsed() uint64 {
+	iter := t.bst.Iterator()
+	var total uint64
+	for iter.Valid() {
+		total += iter.Value()
+		iter.Next()
+	}
+	return total + t.other
+}
+
+func (t *measuringTape) measure(value reflect.Value) {
+	// We only need to measure outbound references. So we don't care about the size of the pointer itself
+	// if value is a pointer, since that is either passed by value (not on heap) or accounted for in the
+	// type that contains the pointer (which we'll have already measured).
+
+	switch value.Kind() {
+	case reflect.Pointer:
+		if !t.insert(value.Pointer(), uint64(value.Type().Elem().Size())) {
+			return
+		}
+		t.measure(value.Elem())
+
+	case reflect.Slice:
+		if !t.insert(value.Pointer(), uint64(value.Cap())*uint64(value.Type().Elem().Size())) {
+			return
+		}
+		for i := 0; i < value.Len(); i++ {
+			t.measure(value.Index(i))
+		}
+
+	case reflect.Chan:
+		if !t.insert(value.Pointer(), uint64(value.Cap())*uint64(value.Type().Elem().Size())) {
+			return
+		}
+		// no way to query for objects in the channel's buffer :(
+
+	case reflect.Map:
+		const mapHdrSz = 48 // estimate based on struct hmap in runtime/map.go
+		if !t.insert(value.Pointer(), mapHdrSz) {
+			return
+		}
+
+		// Can't really get pointers to bucket arrays,
+		// so we estimate their size and add them via t.other.
+		buckets := numBuckets(value.Len())
+		// estimate based on struct bmap in runtime/map.go
+		bucketSz := uint64(8 * (value.Type().Key().Size() + value.Type().Elem().Size() + 1))
+		t.other += uint64(buckets) * bucketSz
+
+		for iter := value.MapRange(); iter.Next(); {
+			t.measure(iter.Key())
+			t.measure(iter.Value())
+		}
+
+	case reflect.Interface:
+		v := value.Elem()
+		if v.IsValid() {
+			if !isReference(v.Kind()) {
+				t.other += uint64(v.Type().Size())
+			}
+			t.measure(v)
+		}
+
+	case reflect.String:
+		str := value.String()
+		hdr := (*reflect.StringHeader)(unsafe.Pointer(&str))
+		t.insert(hdr.Data, uint64(hdr.Len))
+
+	case reflect.Struct:
+		for i := 0; i < value.NumField(); i++ {
+			t.measure(value.Field(i))
+		}
+
+	default:
+		// nothing to do
+	}
+}
+
+func numBuckets(mapSize int) int {
+	// each bucket holds 8 entries
+	buckets := mapSize / 8
+	if mapSize > buckets*8 {
+		buckets++
+	}
+	// Number of buckets is a power of two (map doubles each
+	// time it grows).
+	highestBit := 63 - bits.LeadingZeros64(uint64(buckets))
+	if highestBit >= 0 {
+		powerOf2 := 1 << highestBit
+		if buckets > powerOf2 {
+			powerOf2 <<= 1
+		}
+		buckets = powerOf2
+	}
+	return buckets
+}
+
+func isReference(k reflect.Kind) bool {
+	switch k {
+	case reflect.Pointer, reflect.Chan, reflect.Map, reflect.Func:
+		return true
+	default:
+		return false
+	}
+}
diff --git a/internal/benchmarks/measure_test.go b/internal/benchmarks/measure_test.go
new file mode 100644
index 00000000..517909dc
--- /dev/null
+++ b/internal/benchmarks/measure_test.go
@@ -0,0 +1,157 @@
+// Copyright 2020-2022 Buf Technologies, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package benchmarks
+
+import (
+	"math/bits"
+	"reflect"
+	"testing"
+
+	"github.com/igrmk/treemap/v2"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestMeasuringTapeInsert(t *testing.T) {
+	t.Parallel()
+
+	mt := newMeasuringTape()
+	assert.True(t, mt.insert(100, 300)) // 100 -> 400
+	verifyMap(t, mt.bst, 100, 400)
+
+	// wholly contained
+	assert.False(t, mt.insert(100, 300))
+	assert.False(t, mt.insert(150, 200))
+
+	// extends range start
+	assert.True(t, mt.insert(50, 300)) // 50 -> 350
+	verifyMap(t, mt.bst, 50, 400)
+
+	// extends range end
+	assert.True(t, mt.insert(300, 175)) // 300 -> 475
+	verifyMap(t, mt.bst, 50, 475)
+
+	// new range above
+	assert.True(t, mt.insert(1500, 100)) // 1500 -> 1600
+	verifyMap(t, mt.bst, 50, 475, 1500, 1600)
+
+	// new range below
+	assert.True(t, mt.insert(10, 10)) // 10 -> 20
+	verifyMap(t, mt.bst, 10, 20, 50, 475, 1500, 1600)
+
+	// new range above
+	assert.True(t, mt.insert(25000, 50000)) // 25,000 -> 75,000
+	verifyMap(t, mt.bst, 10, 20, 50, 475, 1500, 1600, 25000, 75000)
+
+	// new interior range
+	assert.True(t, mt.insert(1700, 300)) // 1700 -> 2000
+	verifyMap(t, mt.bst, 10, 20, 50, 475, 1500, 1600, 1700, 2000, 25000, 75000)
+
+	// new interior range
+	assert.True(t, mt.insert(2100, 300)) // 2100 -> 2400
+	verifyMap(t, mt.bst, 10, 20, 50, 475, 1500, 1600, 1700, 2000, 2100, 2400, 25000, 75000)
+
+	// matches range boundary, extends end
+	assert.True(t, mt.insert(2400, 100)) // 2400 -> 2500
+	verifyMap(t, mt.bst, 10, 20, 50, 475, 1500, 1600, 1700, 2000, 2100, 2500, 25000, 75000)
+
+	// matches both adjacent range boundaries, collapses
+	assert.True(t, mt.insert(1600, 100)) // 1600 -> 1700
+	verifyMap(t, mt.bst, 10, 20, 50, 475, 1500, 2000, 2100, 2500, 25000, 75000)
+
+	// matches range boundary, extends start
+	assert.True(t, mt.insert(24000, 1000)) // 24,000 -> 25,000
+	verifyMap(t, mt.bst, 10, 20, 50, 475, 1500, 2000, 2100, 2500, 24000, 75000)
+
+	// encompasses many ranges, collapses
+	assert.True(t, mt.insert(10, 3000)) // 10 -> 3010
+	verifyMap(t, mt.bst, 10, 3010, 24000, 75000)
+
+	// wholly contained
+	assert.False(t, mt.insert(1500, 1510)) // 1500 -> 3010
+
+	mt.other = 99
+	assert.Equal(t, 54099, int(mt.memoryUsed()))
+}
+
+func TestMeasuringTapeMeasure(t *testing.T) {
+	t.Parallel()
+
+	mt := newMeasuringTape()
+	bytes := make([]byte, 1000000)
+	mt.measure(reflect.ValueOf(bytes))
+	require.Equal(t, uint64(1000000), mt.memoryUsed())
+	// these do nothing since they are part of already-measured slice
+	mt.measure(reflect.ValueOf(bytes[0:10]))
+	mt.measure(reflect.ValueOf(bytes[1000:10000]))
+	require.Equal(t, uint64(1000000), mt.memoryUsed())
+
+	int64s := make([]int64, 1000000)
+	mt.measure(reflect.ValueOf(int64s))
+	require.Equal(t, uint64(9000000), mt.memoryUsed())
+
+	int64ptrs := make([]*int64, 1000000)
+	for i := range int64ptrs {
+		int64ptrs[i] = &int64s[i]
+	}
+	mt.measure(reflect.ValueOf(int64ptrs))
+	// increase is only the size of slice, not pointed-to values, since all pointers
+	// point to locations in already-measured slice above
+	ptrsSz := uint64(1000000 * reflect.TypeOf(uintptr(0)).Size())
+	require.Equal(t, 9000000+ptrsSz, mt.memoryUsed())
+}
+
+func verifyMap(t *testing.T, tree *treemap.TreeMap[uintptr, uint64], ranges ...uintptr) {
+	t.Helper()
+	require.Equal(t, 0, len(ranges)%2, "ranges must be even number of values")
+
+	iter := tree.Iterator()
+	for i := 0; i < len(ranges); i += 2 {
+		require.True(t, iter.Valid())
+		entryEnd := iter.Key()
+		entryStart := entryEnd - uintptr(iter.Value())
+		type pair struct {
+			start, end uintptr
+		}
+		expected := pair{ranges[i], ranges[i+1]}
+		actual := pair{entryStart, entryEnd}
+		require.Equal(t, expected, actual)
+		iter.Next()
+	}
+}
+
+func TestNumBuckets(t *testing.T) {
+	t.Parallel()
+
+	assert.Equal(t, 0, numBuckets(0))
+	assert.Equal(t, 1, numBuckets(8))
+	assert.Equal(t, 2, numBuckets(9))
+	assert.Equal(t, 2, numBuckets(16))
+	assert.Equal(t, 4, numBuckets(17))
+	assert.Equal(t, 4, numBuckets(32))
+	assert.Equal(t, 8, numBuckets(33))
+
+	check := func(sz int) {
+		b := numBuckets(sz)
+		// power of 2
+		assert.Equal(t, 1, bits.OnesCount(uint(b)))
+		// that fits given size (each bucket holds 8 entries)
+		assert.True(t, b*4 < sz)
+		assert.True(t, b*8 >= sz)
+	}
+	check(7364)
+	check(1234567)
+	check(918373645623)
+}
diff --git a/linker/descriptors.go b/linker/descriptors.go
index c61a6ada..361f3b6f 100644
--- a/linker/descriptors.go
+++ b/linker/descriptors.go
@@ -76,6 +76,11 @@ var _ protoreflect.FileDescriptor = (*result)(nil)
 var _ Result = (*result)(nil)
 var _ protoutil.DescriptorProtoWrapper = (*result)(nil)
 
+func (r *result) RemoveAST() {
+	r.Result = parser.ResultWithoutAST(r.FileDescriptorProto())
+	r.optionQualifiedNames = nil
+}
+
 func (r *result) AsProto() proto.Message {
 	return r.FileDescriptorProto()
 }
@@ -157,11 +162,11 @@ func (r *result) SourceLocations() protoreflect.SourceLocations {
 	return &r.srcLocations
 }
 
-func computeSourceLocIndex(locs []protoreflect.SourceLocation) map[interface{}]protoreflect.SourceLocation {
-	index := map[interface{}]protoreflect.SourceLocation{}
-	for _, loc := range locs {
+func computeSourceLocIndex(locs []protoreflect.SourceLocation) map[interface{}]int {
+	index := map[interface{}]int{}
+	for i, loc := range locs {
 		if loc.Next == 0 {
-			index[pathKey(loc.Path)] = loc
+			index[pathKey(loc.Path)] = i
 		}
 	}
 	return index
@@ -373,7 +378,7 @@ type srcLocs struct {
 	protoreflect.SourceLocations
 	file  *result
 	locs  []protoreflect.SourceLocation
-	index map[interface{}]protoreflect.SourceLocation
+	index map[interface{}]int
 }
 
 func (s *srcLocs) Len() int {
@@ -385,7 +390,11 @@ func (s *srcLocs) Get(i int) protoreflect.SourceLocation {
 }
 
 func (s *srcLocs) ByPath(p protoreflect.SourcePath) protoreflect.SourceLocation {
-	return s.index[pathKey(p)]
+	index, ok := s.index[pathKey(p)]
+	if !ok {
+		return protoreflect.SourceLocation{}
+	}
+	return s.locs[index]
 }
 
 func (s *srcLocs) ByDescriptor(d protoreflect.Descriptor) protoreflect.SourceLocation {
diff --git a/linker/linker.go b/linker/linker.go
index 5acce786..c9e6e84e 100644
--- a/linker/linker.go
+++ b/linker/linker.go
@@ -152,6 +152,9 @@ type Result interface {
 	// is otherwise not useful since all option values are treated as
 	// unknown.
 	CanonicalProto() *descriptorpb.FileDescriptorProto
+
+	// RemoveAST drops the AST information from this result.
+	RemoveAST()
 }
 
 // ErrorUnusedImport may be passed to a warning reporter when an unused
diff --git a/linker/symbols.go b/linker/symbols.go
index f7af5778..4bc93f10 100644
--- a/linker/symbols.go
+++ b/linker/symbols.go
@@ -43,7 +43,12 @@ type packageSymbols struct {
 	children map[protoreflect.FullName]*packageSymbols
 	files    map[protoreflect.FileDescriptor]struct{}
 	symbols  map[protoreflect.FullName]symbolEntry
-	exts     map[protoreflect.FullName]map[protoreflect.FieldNumber]ast.SourcePos
+	exts     map[extNumber]ast.SourcePos
+}
+
+type extNumber struct {
+	extendee protoreflect.FullName
+	tag      protoreflect.FieldNumber
 }
 
 type symbolEntry struct {
@@ -361,7 +366,7 @@ func (s *packageSymbols) commitFileLocked(f protoreflect.FileDescriptor) {
 		s.symbols = map[protoreflect.FullName]symbolEntry{}
 	}
 	if s.exts == nil {
-		s.exts = map[protoreflect.FullName]map[protoreflect.FieldNumber]ast.SourcePos{}
+		s.exts = map[extNumber]ast.SourcePos{}
 	}
 	_ = walk.Descriptors(f, func(d protoreflect.Descriptor) error {
 		pos := sourcePositionFor(d)
@@ -503,7 +508,7 @@ func (s *packageSymbols) commitResultLocked(r *result) {
 		s.symbols = map[protoreflect.FullName]symbolEntry{}
 	}
 	if s.exts == nil {
-		s.exts = map[protoreflect.FullName]map[protoreflect.FieldNumber]ast.SourcePos{}
+		s.exts = map[extNumber]ast.SourcePos{}
 	}
 	_ = walk.DescriptorProtos(r.FileDescriptorProto(), func(fqn protoreflect.FullName, d proto.Message) error {
 		pos := nameStart(r.FileNode(), r.Node(d))
@@ -537,20 +542,16 @@ func (s *packageSymbols) addExtension(extendee protoreflect.FullName, tag protor
 	defer s.mu.Unlock()
 
 	if s.exts == nil {
-		s.exts = map[protoreflect.FullName]map[protoreflect.FieldNumber]ast.SourcePos{}
+		s.exts = map[extNumber]ast.SourcePos{}
 	}
 
-	usedExtTags := s.exts[extendee]
-	if usedExtTags == nil {
-		usedExtTags = map[protoreflect.FieldNumber]ast.SourcePos{}
-		s.exts[extendee] = usedExtTags
-	}
-	if existing, ok := usedExtTags[tag]; ok {
+	extNum := extNumber{extendee: extendee, tag: tag}
+	if existing, ok := s.exts[extNum]; ok {
 		if err := handler.HandleErrorf(pos, "extension with tag %d for message %s already defined at %v", tag, extendee, existing); err != nil {
 			return err
 		}
 	} else {
-		usedExtTags[tag] = pos
+		s.exts[extNum] = pos
 	}
 	return nil
 }
diff --git a/linker/symbols_test.go b/linker/symbols_test.go
index 02a06aea..ad1667ae 100644
--- a/linker/symbols_test.go
+++ b/linker/symbols_test.go
@@ -124,18 +124,14 @@ func TestSymbolsImport(t *testing.T) {
 			assert.Contains(t, syms, protoreflect.FullName("foo.bar.s"))
 			assert.Contains(t, syms, protoreflect.FullName("foo.bar.xtra"))
 			exts := pkg.exts
-			assert.Equal(t, 1, len(exts))
-			extNums := exts["foo.bar.Foo"]
-			assert.Equal(t, 2, len(extNums))
-			assert.Contains(t, extNums, protoreflect.FieldNumber(10))
-			assert.Contains(t, extNums, protoreflect.FieldNumber(11))
+			assert.Equal(t, 2, len(exts))
+			assert.Contains(t, exts, extNumber{"foo.bar.Foo", 10})
+			assert.Contains(t, exts, extNumber{"foo.bar.Foo", 11})
 
 			pkg = s.getPackage("google.protobuf")
 			exts = pkg.exts
 			assert.Equal(t, 1, len(exts))
-			extNums = exts["google.protobuf.FieldOptions"]
-			assert.Equal(t, 1, len(extNums))
-			assert.Contains(t, extNums, protoreflect.FieldNumber(20000))
+			assert.Contains(t, exts, extNumber{"google.protobuf.FieldOptions", 20000})
 		})
 	}
 }
@@ -184,27 +180,16 @@ func TestSymbolExtensions(t *testing.T) {
 
 	pkg := s.getPackage("foo.bar")
 	exts := pkg.exts
-	assert.Equal(t, 1, len(exts))
-	extNums := exts["foo.bar.Foo"]
-	assert.Equal(t, 2, len(extNums))
-	assert.Contains(t, extNums, protoreflect.FieldNumber(11))
-	assert.Contains(t, extNums, protoreflect.FieldNumber(12))
+	assert.Equal(t, 2, len(exts))
+	assert.Contains(t, exts, extNumber{"foo.bar.Foo", 11})
+	assert.Contains(t, exts, extNumber{"foo.bar.Foo", 12})
 
 	pkg = s.getPackage("google.protobuf")
 	exts = pkg.exts
 	assert.Equal(t, 3, len(exts))
-	assert.Contains(t, exts, protoreflect.FullName("google.protobuf.FileOptions"))
-	assert.Contains(t, exts, protoreflect.FullName("google.protobuf.FieldOptions"))
-	assert.Contains(t, exts, protoreflect.FullName("google.protobuf.MessageOptions"))
-	extNums = exts["google.protobuf.FileOptions"]
-	assert.Equal(t, 1, len(extNums))
-	assert.Contains(t, extNums, protoreflect.FieldNumber(10101))
-	extNums = exts["google.protobuf.FieldOptions"]
-	assert.Equal(t, 1, len(extNums))
-	assert.Contains(t, extNums, protoreflect.FieldNumber(10101))
-	extNums = exts["google.protobuf.MessageOptions"]
-	assert.Equal(t, 1, len(extNums))
-	assert.Contains(t, extNums, protoreflect.FieldNumber(10101))
+	assert.Contains(t, exts, extNumber{"google.protobuf.FileOptions", 10101})
+	assert.Contains(t, exts, extNumber{"google.protobuf.FieldOptions", 10101})
+	assert.Contains(t, exts, extNumber{"google.protobuf.MessageOptions", 10101})
 }
 
 func parseAndLink(t *testing.T, contents string) Result {