diff --git a/src/cmd/5l/5.out.h b/src/cmd/5l/5.out.h
index 1dea18c49e..23ff6210e3 100644
--- a/src/cmd/5l/5.out.h
+++ b/src/cmd/5l/5.out.h
@@ -276,7 +276,7 @@ enum	as
 /*
  * this is the ranlib header
  */
-#define	SYMDEF	"__.SYMDEF"
+#define	SYMDEF	"__.GOSYMDEF"
 
 /*
  * this is the simulated IEEE floating point
diff --git a/src/cmd/6l/6.out.h b/src/cmd/6l/6.out.h
index cd861c038e..01c2ba840b 100644
--- a/src/cmd/6l/6.out.h
+++ b/src/cmd/6l/6.out.h
@@ -865,7 +865,7 @@ enum
 /*
  * this is the ranlib header
  */
-#define	SYMDEF	"__.SYMDEF"
+#define	SYMDEF	"__.GOSYMDEF"
 
 /*
  * this is the simulated IEEE floating point
diff --git a/src/cmd/8l/8.out.h b/src/cmd/8l/8.out.h
index 924ba93901..49e046207b 100644
--- a/src/cmd/8l/8.out.h
+++ b/src/cmd/8l/8.out.h
@@ -547,7 +547,7 @@ enum
 /*
  * this is the ranlib header
  */
-#define	SYMDEF	"__.SYMDEF"
+#define	SYMDEF	"__.GOSYMDEF"
 
 /*
  * this is the simulated IEEE floating point
diff --git a/src/cmd/gc/lex.c b/src/cmd/gc/lex.c
index 0788a61514..3ef3fcc746 100644
--- a/src/cmd/gc/lex.c
+++ b/src/cmd/gc/lex.c
@@ -480,7 +480,7 @@ skiptopkgdef(Biobuf *b)
 	if(memcmp(p, "!<arch>\n", 8) != 0)
 		return 0;
 	/* symbol table is first; skip it */
-	sz = arsize(b, "__.SYMDEF");
+	sz = arsize(b, "__.GOSYMDEF");
 	if(sz < 0)
 		return 0;
 	Bseek(b, sz, 1);
diff --git a/src/cmd/ld/lib.c b/src/cmd/ld/lib.c
index 2385809dbf..2026707c2f 100644
--- a/src/cmd/ld/lib.c
+++ b/src/cmd/ld/lib.c
@@ -366,7 +366,7 @@ objfile(char *file, char *pkg)
 		return;
 	}
 	
-	/* skip over __.SYMDEF */
+	/* skip over __.GOSYMDEF */
 	off = Boffset(f);
 	if((l = nextar(f, off, &arhdr)) <= 0) {
 		diag("%s: short read on archive file symbol header", file);
@@ -402,7 +402,7 @@ objfile(char *file, char *pkg)
 	 * the individual symbols that are unused.
 	 *
 	 * loading every object will also make it possible to
-	 * load foreign objects not referenced by __.SYMDEF.
+	 * load foreign objects not referenced by __.GOSYMDEF.
 	 */
 	for(;;) {
 		l = nextar(f, off, &arhdr);
diff --git a/src/cmd/nm/nm.c b/src/cmd/nm/nm.c
index 845b6c773a..6682390358 100644
--- a/src/cmd/nm/nm.c
+++ b/src/cmd/nm/nm.c
@@ -43,7 +43,7 @@ enum{
 
 char	*errs;			/* exit status */
 char	*filename;		/* current file */
-char	symname[]="__.SYMDEF";	/* table of contents file name */
+char	symname[]="__.GOSYMDEF";	/* table of contents file name */
 int	multifile;		/* processing multiple files */
 int	aflag;
 int	gflag;
diff --git a/src/cmd/pack/ar.c b/src/cmd/pack/ar.c
index 990094e5db..7053f841f3 100644
--- a/src/cmd/pack/ar.c
+++ b/src/cmd/pack/ar.c
@@ -111,7 +111,7 @@ char	*opt =		"uvnbailogS";
 char	artemp[] =	"/tmp/vXXXXX";
 char	movtemp[] =	"/tmp/v1XXXXX";
 char	tailtemp[] =	"/tmp/v2XXXXX";
-char	symdef[] =	"__.SYMDEF";
+char	symdef[] =	"__.GOSYMDEF";
 char	pkgdef[] =	"__.PKGDEF";
 
 int	aflag;				/* command line flags */
diff --git a/src/pkg/exp/types/exportdata.go b/src/pkg/exp/types/exportdata.go
index bca2038804..22190153bb 100644
--- a/src/pkg/exp/types/exportdata.go
+++ b/src/pkg/exp/types/exportdata.go
@@ -52,13 +52,14 @@ func FindGcExportData(r *bufio.Reader) (err error) {
 		var name string
 		var size int
 
-		// First entry should be __.SYMDEF.
+		// First entry should be __.GOSYMDEF.
+		// Older archives used __.SYMDEF, so allow that too.
 		// Read and discard.
 		if name, size, err = readGopackHeader(r); err != nil {
 			return
 		}
-		if name != "__.SYMDEF" {
-			err = errors.New("go archive does not begin with __.SYMDEF")
+		if name != "__.SYMDEF" && name != "__.GOSYMDEF" {
+			err = errors.New("go archive does not begin with __.SYMDEF or __.GOSYMDEF")
 			return
 		}
 		const block = 4096