cmd/gc: initialize t->width in dgcsym() if required

Update #5291.

R=golang-dev, daniel.morsing, iant, r
CC=golang-dev
https://golang.org/cl/8663052

diff --git a/src/cmd/gc/reflect.c b/src/cmd/gc/reflect.c
index d128bf1174931df85da3c236a53149a9acb0dd09..fc182b03e67cb48d69569113f66bf2785780ec13 100644 (file)
--- a/src/cmd/gc/reflect.c
+++ b/src/cmd/gc/reflect.c
@@ -1046,6 +1046,9 @@ dgcsym1(Sym *s, int ot, Type *t, vlong *off, int stack_size)
 
        if(t->align > 0 && (*off % t->align) != 0)
                fatal("dgcsym1: invalid initial alignment, %T", t);
+
+       if(t->width == BADWIDTH)
+               dowidth(t);
        
        switch(t->etype) {
        case TINT8:
@@ -1141,6 +1144,8 @@ dgcsym1(Sym *s, int ot, Type *t, vlong *off, int stack_size)
        case TARRAY:
                if(t->bound < -1)
                        fatal("dgcsym1: invalid bound, %T", t);
+               if(t->type->width == BADWIDTH)
+                       dowidth(t->type);
                if(isslice(t)) {
                        // NOTE: Any changes here need to be made to reflect.SliceOf as well.
                        // struct { byte* array; uint32 len; uint32 cap; }
@@ -1214,6 +1219,9 @@ dgcsym(Type *t)
                return s;
        s->flags |= SymGcgen;
 
+       if(t->width == BADWIDTH)
+               dowidth(t);
+
        ot = 0;
        off = 0;
        ot = duintptr(s, ot, t->width);

diff --git a/test/fixedbugs/issue5291.dir/pkg1.go b/test/fixedbugs/issue5291.dir/pkg1.go
new file mode 100644 (file)
index 0000000..b1c893a
--- /dev/null
+++ b/test/fixedbugs/issue5291.dir/pkg1.go
@@ -0,0 +1,34 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pkg1
+
+import (
+       "runtime"
+)
+
+type T2 *[]string
+
+type Data struct {
+       T1 *[]T2
+}
+
+func CrashCall() (err error) {
+       var d Data
+
+       for count := 0; count < 10; count++ {
+               runtime.GC()
+
+               len := 2 // crash when >=2
+               x := make([]T2, len)
+
+               d = Data{T1: &x}
+
+               for j := 0; j < len; j++ {
+                       y := make([]string, 1)
+                       (*d.T1)[j] = &y
+               }
+       }
+       return nil
+}

diff --git a/test/fixedbugs/issue5291.dir/prog.go b/test/fixedbugs/issue5291.dir/prog.go
new file mode 100644 (file)
index 0000000..8301091
--- /dev/null
+++ b/test/fixedbugs/issue5291.dir/prog.go
@@ -0,0 +1,17 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+       "./pkg1"
+)
+
+type message struct { // Presence of this creates a crash
+       data pkg1.Data
+}
+
+func main() {
+       pkg1.CrashCall()
+}

diff --git a/test/fixedbugs/issue5291.go b/test/fixedbugs/issue5291.go
new file mode 100644 (file)
index 0000000..00d2ada
--- /dev/null
+++ b/test/fixedbugs/issue5291.go
@@ -0,0 +1,9 @@
+// rundir
+
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 5291: GC crash
+
+package ignored