libgo: update to go1.8rc2

    
    Fix a bug in the generation of the hash value in reflect.FuncOf.
    
    The merge script missed a bunch of testdata files over the years.
    Copy them over.
    
    Reviewed-on: https://go-review.googlesource.com/35570

From-SVN: r244835

5 files changed, 78 insertions, 17 deletions

diff --git a/libgo/go/compress/bzip2/bzip2_test.go b/libgo/go/compress/bzip2/bzip2_test.go
index a6c3080..95fb1895 100644
--- a/libgo/go/compress/bzip2/bzip2_test.go
+++ b/libgo/go/compress/bzip2/bzip2_test.go
@@ -204,12 +204,6 @@ func TestMTF(t *testing.T) {
 	}
 }
 
-var (
-	digits = mustLoadFile("testdata/e.txt.bz2")
-	twain  = mustLoadFile("testdata/Mark.Twain-Tom.Sawyer.txt.bz2")
-	random = mustLoadFile("testdata/random.data.bz2")
-)
-
 func benchmarkDecode(b *testing.B, compressed []byte) {
 	// Determine the uncompressed size of testfile.
 	uncompressedSize, err := io.Copy(ioutil.Discard, NewReader(bytes.NewReader(compressed)))
@@ -227,6 +221,18 @@ func benchmarkDecode(b *testing.B, compressed []byte) {
 	}
 }
 
-func BenchmarkDecodeDigits(b *testing.B) { benchmarkDecode(b, digits) }
-func BenchmarkDecodeTwain(b *testing.B)  { benchmarkDecode(b, twain) }
-func BenchmarkDecodeRand(b *testing.B)   { benchmarkDecode(b, random) }
+func BenchmarkDecodeDigits(b *testing.B) {
+	digits := mustLoadFile("testdata/e.txt.bz2")
+	b.ResetTimer()
+	benchmarkDecode(b, digits)
+}
+func BenchmarkDecodeTwain(b *testing.B) {
+	twain := mustLoadFile("testdata/Mark.Twain-Tom.Sawyer.txt.bz2")
+	b.ResetTimer()
+	benchmarkDecode(b, twain)
+}
+func BenchmarkDecodeRand(b *testing.B) {
+	random := mustLoadFile("testdata/random.data.bz2")
+	b.ResetTimer()
+	benchmarkDecode(b, random)
+}
diff --git a/libgo/go/compress/flate/deflate.go b/libgo/go/compress/flate/deflate.go
index 97265b3..4d6a535 100644
--- a/libgo/go/compress/flate/deflate.go
+++ b/libgo/go/compress/flate/deflate.go
@@ -136,14 +136,17 @@ func (d *compressor) fillDeflate(b []byte) int {
 			delta := d.hashOffset - 1
 			d.hashOffset -= delta
 			d.chainHead -= delta
-			for i, v := range d.hashPrev {
+
+			// Iterate over slices instead of arrays to avoid copying
+			// the entire table onto the stack (Issue #18625).
+			for i, v := range d.hashPrev[:] {
 				if int(v) > delta {
 					d.hashPrev[i] = uint32(int(v) - delta)
 				} else {
 					d.hashPrev[i] = 0
 				}
 			}
-			for i, v := range d.hashHead {
+			for i, v := range d.hashHead[:] {
 				if int(v) > delta {
 					d.hashHead[i] = uint32(int(v) - delta)
 				} else {
diff --git a/libgo/go/compress/flate/deflate_test.go b/libgo/go/compress/flate/deflate_test.go
index 521a260..fbea761 100644
--- a/libgo/go/compress/flate/deflate_test.go
+++ b/libgo/go/compress/flate/deflate_test.go
@@ -12,6 +12,7 @@ import (
 	"io"
 	"io/ioutil"
 	"reflect"
+	"runtime/debug"
 	"sync"
 	"testing"
 )
@@ -864,3 +865,33 @@ func TestBestSpeedMaxMatchOffset(t *testing.T) {
 		}
 	}
 }
+
+func TestMaxStackSize(t *testing.T) {
+	// This test must not run in parallel with other tests as debug.SetMaxStack
+	// affects all goroutines.
+	n := debug.SetMaxStack(1 << 16)
+	defer debug.SetMaxStack(n)
+
+	var wg sync.WaitGroup
+	defer wg.Wait()
+
+	b := make([]byte, 1<<20)
+	for level := HuffmanOnly; level <= BestCompression; level++ {
+		// Run in separate goroutine to increase probability of stack regrowth.
+		wg.Add(1)
+		go func(level int) {
+			defer wg.Done()
+			zw, err := NewWriter(ioutil.Discard, level)
+			if err != nil {
+				t.Errorf("level %d, NewWriter() = %v, want nil", level, err)
+			}
+			if n, err := zw.Write(b); n != len(b) || err != nil {
+				t.Errorf("level %d, Write() = (%d, %v), want (%d, nil)", level, n, err, len(b))
+			}
+			if err := zw.Close(); err != nil {
+				t.Errorf("level %d, Close() = %v, want nil", level, err)
+			}
+			zw.Reset(ioutil.Discard)
+		}(level)
+	}
+}
diff --git a/libgo/go/compress/flate/deflatefast.go b/libgo/go/compress/flate/deflatefast.go
index a1636a3..08298b7 100644
--- a/libgo/go/compress/flate/deflatefast.go
+++ b/libgo/go/compress/flate/deflatefast.go
@@ -60,7 +60,7 @@ func newDeflateFast() *deflateFast {
 func (e *deflateFast) encode(dst []token, src []byte) []token {
 	// Ensure that e.cur doesn't wrap.
 	if e.cur > 1<<30 {
-		*e = deflateFast{cur: maxStoreBlockSize, prev: e.prev[:0]}
+		e.resetAll()
 	}
 
 	// This check isn't in the Snappy implementation, but there, the caller
@@ -265,6 +265,21 @@ func (e *deflateFast) reset() {
 
 	// Protect against e.cur wraparound.
 	if e.cur > 1<<30 {
-		*e = deflateFast{cur: maxStoreBlockSize, prev: e.prev[:0]}
+		e.resetAll()
+	}
+}
+
+// resetAll resets the deflateFast struct and is only called in rare
+// situations to prevent integer overflow. It manually resets each field
+// to avoid causing large stack growth.
+//
+// See https://golang.org/issue/18636.
+func (e *deflateFast) resetAll() {
+	// This is equivalent to:
+	//	*e = deflateFast{cur: maxStoreBlockSize, prev: e.prev[:0]}
+	e.cur = maxStoreBlockSize
+	e.prev = e.prev[:0]
+	for i := range e.table {
+		e.table[i] = tableEntry{}
 	}
 }
diff --git a/libgo/go/compress/gzip/issue14937_test.go b/libgo/go/compress/gzip/issue14937_test.go
index e76d47c..30c1390 100644
--- a/libgo/go/compress/gzip/issue14937_test.go
+++ b/libgo/go/compress/gzip/issue14937_test.go
@@ -9,11 +9,17 @@ import (
 	"testing"
 )
 
-// Per golang.org/issue/14937, check that every .gz file
-// in the tree has a zero mtime.
+// TestGZIPFilesHaveZeroMTimes checks that every .gz file in the tree
+// has a zero MTIME. This is a requirement for the Debian maintainers
+// to be able to have deterministic packages.
+//
+// See https://golang.org/issue/14937.
 func TestGZIPFilesHaveZeroMTimes(t *testing.T) {
-	if testing.Short() && testenv.Builder() == "" {
-		t.Skip("skipping in short mode")
+	// To avoid spurious false positives due to untracked GZIP files that
+	// may be in the user's GOROOT (Issue 18604), we only run this test on
+	// the builders, which should have a clean checkout of the tree.
+	if testenv.Builder() == "" {
+		t.Skip("skipping test on non-builder")
 	}
 	goroot, err := filepath.EvalSymlinks(runtime.GOROOT())
 	if err != nil {