cmd/go/internal: remove unused result parameter

Incomplete Put operation already returns an error.

src/cmd/go/internal/cache/cache.go

@@ -50,9 +50,9 @@ type Cache interface {
 	// As a special case, if the ReadSeeker is of type noVerifyReadSeeker,
 	// the verification from GODEBUG=goverifycache=1 is skipped.
 	//
-	// After a success call to Get, OutputFile(Entry.OutputID) must
+	// After a success call to Put, OutputFile(Entry.OutputID) must
 	// exist on disk for until Close is called (at the end of the process).
-	Put(ActionID, io.ReadSeeker) (_ OutputID, size int64, _ error)
+	Put(ActionID, io.ReadSeeker) (OutputID, error)
 
 	// Close is called at the end of the go process. Implementations can do
 	// cache cleanup work at this phase, or wait for and report any errors from
@@ -504,7 +504,7 @@ type noVerifyReadSeeker struct {
 
 // Put stores the given output in the cache as the output for the action ID.
 // It may read file twice. The content of file must not change between the two passes.
-func (c *DiskCache) Put(id ActionID, file io.ReadSeeker) (OutputID, int64, error) {
+func (c *DiskCache) Put(id ActionID, file io.ReadSeeker) (OutputID, error) {
 	wrapper, isNoVerify := file.(noVerifyReadSeeker)
 	if isNoVerify {
 		file = wrapper.ReadSeeker
@@ -515,7 +515,7 @@ func (c *DiskCache) Put(id ActionID, file io.ReadSeeker) (OutputID, int64, error
 // PutExecutable is used to store the output as the output for the action ID into a
 // file with the given base name, with the executable mode bit set.
 // It may read file twice. The content of file must not change between the two passes.
-func (c *DiskCache) PutExecutable(id ActionID, name string, file io.ReadSeeker) (OutputID, int64, error) {
+func (c *DiskCache) PutExecutable(id ActionID, name string, file io.ReadSeeker) (OutputID, error) {
 	if name == "" {
 		panic("PutExecutable called without a name")
 	}
@@ -530,19 +530,19 @@ func (c *DiskCache) PutExecutable(id ActionID, name string, file io.ReadSeeker)
 // when GODEBUG=goverifycache=1 is set.
 // It is meant for data that is OK to cache but that we expect to vary slightly from run to run,
 // like test output containing times and the like.
-func PutNoVerify(c Cache, id ActionID, file io.ReadSeeker) (OutputID, int64, error) {
+func PutNoVerify(c Cache, id ActionID, file io.ReadSeeker) (OutputID, error) {
 	return c.Put(id, noVerifyReadSeeker{file})
 }
 
-func (c *DiskCache) put(id ActionID, executableName string, file io.ReadSeeker, allowVerify bool) (OutputID, int64, error) {
+func (c *DiskCache) put(id ActionID, executableName string, file io.ReadSeeker, allowVerify bool) (OutputID, error) {
 	// Compute output ID.
 	h := sha256.New()
 	if _, err := file.Seek(0, 0); err != nil {
-		return OutputID{}, 0, err
+		return OutputID{}, err
 	}
 	size, err := io.Copy(h, file)
 	if err != nil {
-		return OutputID{}, 0, err
+		return OutputID{}, err
 	}
 	var out OutputID
 	h.Sum(out[:0])
@@ -553,16 +553,16 @@ func (c *DiskCache) put(id ActionID, executableName string, file io.ReadSeeker,
 		fileMode = 0o777
 	}
 	if err := c.copyFile(file, executableName, out, size, fileMode); err != nil {
-		return out, size, err
+		return out, err
 	}
 
 	// Add to cache index.
-	return out, size, c.putIndexEntry(id, out, size, allowVerify)
+	return out, c.putIndexEntry(id, out, size, allowVerify)
 }
 
 // PutBytes stores the given bytes in the cache as the output for the action ID.
 func PutBytes(c Cache, id ActionID, data []byte) error {
-	_, _, err := c.Put(id, bytes.NewReader(data))
+	_, err := c.Put(id, bytes.NewReader(data))
 	return err
 }
 

src/cmd/go/internal/cache/prog.go

@@ -378,26 +378,26 @@ func (c *ProgCache) OutputFile(o OutputID) string {
 	return c.outputFile[o]
 }
 
-func (c *ProgCache) Put(a ActionID, file io.ReadSeeker) (_ OutputID, size int64, _ error) {
+func (c *ProgCache) Put(a ActionID, file io.ReadSeeker) (OutputID, error) {
 	// Compute output ID.
 	h := sha256.New()
 	if _, err := file.Seek(0, 0); err != nil {
-		return OutputID{}, 0, err
+		return OutputID{}, err
 	}
 	size, err := io.Copy(h, file)
 	if err != nil {
-		return OutputID{}, 0, err
+		return OutputID{}, err
 	}
 	var out OutputID
 	h.Sum(out[:0])
 
 	if _, err := file.Seek(0, 0); err != nil {
-		return OutputID{}, 0, err
+		return OutputID{}, err
 	}
 
 	if !c.can[cmdPut] {
 		// Child is a read-only cache. Do nothing.
-		return out, size, nil
+		return out, nil
 	}
 
 	// For compatibility with Go 1.23/1.24 GOEXPERIMENT=gocacheprog users, also
@@ -416,13 +416,13 @@ func (c *ProgCache) Put(a ActionID, file io.ReadSeeker) (_ OutputID, size int64,
 		BodySize: size,
 	})
 	if err != nil {
-		return OutputID{}, 0, err
+		return OutputID{}, err
 	}
 	if res.DiskPath == "" {
-		return OutputID{}, 0, errors.New("GOCACHEPROG didn't return DiskPath in put response")
+		return OutputID{}, errors.New("GOCACHEPROG didn't return DiskPath in put response")
 	}
 	c.noteOutputFile(out, res.DiskPath)
-	return out, size, err
+	return out, err
 }
 
 func (c *ProgCache) Close() error {

src/cmd/go/internal/list/list.go

@@ -673,7 +673,7 @@ func runList(ctx context.Context, cmd *base.Command, args []string) {
 					h := cache.NewHash("testmain")
 					h.Write([]byte("testmain\n"))
 					h.Write(data)
-					out, _, err := c.Put(h.Sum(), bytes.NewReader(data))
+					out, err := c.Put(h.Sum(), bytes.NewReader(data))
 					if err != nil {
 						base.Fatalf("%s", err)
 					}

src/cmd/go/internal/work/action.go

@@ -516,7 +516,7 @@ func (p *pgoActor) Act(b *Builder, ctx context.Context, a *Action) error {
 		}
 
 		c := cache.Default()
-		outputID, _, err := c.Put(a.actionID, r)
+		outputID, err := c.Put(a.actionID, r)
 		r.Close()
 		if err != nil {
 			return fmt.Errorf("error adding target to cache: %w", err)

src/cmd/go/internal/work/buildid.go

@@ -746,7 +746,7 @@ func (b *Builder) updateBuildID(a *Action, target string) error {
 			if a.output == nil {
 				panic("internal error: a.output not set")
 			}
-			outputID, _, err := c.Put(a.actionID, r)
+			outputID, err := c.Put(a.actionID, r)
 			r.Close()
 			if err == nil && cfg.BuildX {
 				sh.ShowCmd("", "%s # internal", joinUnambiguously(str.StringList("cp", target, c.OutputFile(outputID))))
@@ -770,7 +770,7 @@ func (b *Builder) updateBuildID(a *Action, target string) error {
 			if name == "" {
 				name = path.Base(a.Package.ImportPath)
 			}
-			outputID, _, err := c.PutExecutable(a.actionID, name+cfg.ExeSuffix, r)
+			outputID, err := c.PutExecutable(a.actionID, name+cfg.ExeSuffix, r)
 			r.Close()
 			if err == nil && cfg.BuildX {
 				sh.ShowCmd("", "%s # internal", joinUnambiguously(str.StringList("cp", target, c.OutputFile(outputID))))

src/cmd/go/internal/work/exec.go

@@ -1028,7 +1028,7 @@ func (b *Builder) cacheObjdirFile(a *Action, c cache.Cache, name string) error {
 		return err
 	}
 	defer f.Close()
-	_, _, err = c.Put(cache.Subkey(a.actionID, name), f)
+	_, err = c.Put(cache.Subkey(a.actionID, name), f)
 	return err
 }