cmd/gc: fix inlining bug for composite literals in if statements.

Fixes #4230.

R=golang-dev, rsc
CC=golang-dev, remy
https://golang.org/cl/6640056

diff --git a/src/cmd/gc/fmt.c b/src/cmd/gc/fmt.c
index ec6d3d0cdfea7ea34f6f9f1b5826c378ec8f17f2..6945e9c8e3d976bcadbe967a209562b28d75bf99 100644 (file)
--- a/src/cmd/gc/fmt.c
+++ b/src/cmd/gc/fmt.c
@@ -1161,7 +1161,7 @@ exprfmt(Fmt *f, Node *n, int prec)
        case OCOMPLIT:
                if(fmtmode == FErr)
                        return fmtstrcpy(f, "composite literal");
-               return fmtprint(f, "%N{ %,H }", n->right, n->list);
+               return fmtprint(f, "(%N{ %,H })", n->right, n->list);
 
        case OPTRLIT:
                if(fmtmode == FExp && n->left->implicit)
@@ -1172,8 +1172,8 @@ exprfmt(Fmt *f, Node *n, int prec)
                if(fmtmode == FExp) {   // requires special handling of field names
                        if(n->implicit)
                                fmtstrcpy(f, "{");
-                       else 
-                               fmtprint(f, "%T{", n->type);
+                       else
+                               fmtprint(f, "(%T{", n->type);
                        for(l=n->list; l; l=l->next) {
                                // another special case: if n->left is an embedded field of builtin type,
                                // it needs to be non-qualified.  Can't figure that out in %S, so do it here
@@ -1190,6 +1190,8 @@ exprfmt(Fmt *f, Node *n, int prec)
                                else
                                        fmtstrcpy(f, " ");
                        }
+                       if(!n->implicit)
+                               return fmtstrcpy(f, "})");
                        return fmtstrcpy(f, "}");
                }
                // fallthrough
@@ -1200,7 +1202,7 @@ exprfmt(Fmt *f, Node *n, int prec)
                        return fmtprint(f, "%T literal", n->type);
                if(fmtmode == FExp && n->implicit)
                        return fmtprint(f, "{ %,H }", n->list);
-               return fmtprint(f, "%T{ %,H }", n->type, n->list);
+               return fmtprint(f, "(%T{ %,H })", n->type, n->list);
 
        case OKEY:
                if(n->left && n->right)

diff --git a/test/fixedbugs/bug465.dir/a.go b/test/fixedbugs/bug465.dir/a.go
new file mode 100644 (file)
index 0000000..c5d410d
--- /dev/null
+++ b/test/fixedbugs/bug465.dir/a.go
@@ -0,0 +1,61 @@
+// Copyright 2012 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 a
+
+type T struct{ A, B int }
+
+type A []int
+
+type M map[int]int
+
+func F1() int {
+       if (T{1, 2}) == (T{3, 4}) {
+               return 1
+       }
+       return 0
+}
+
+func F2() int {
+       if (M{1: 2}) == nil {
+               return 1
+       }
+       return 0
+}
+
+func F3() int {
+       if nil == (A{}) {
+               return 1
+       }
+       return 0
+}
+
+func F4() int {
+       if a := (A{}); a == nil {
+               return 1
+       }
+       return 0
+}
+
+func F5() int {
+       for k, v := range (M{1: 2}) {
+               return v - k
+       }
+       return 0
+}
+
+func F6() int {
+       switch a := (T{1, 1}); a == (T{1, 2}) {
+       default:
+               return 1
+       }
+       return 0
+}
+
+func F7() int {
+       for m := (M{}); len(m) < (T{1, 2}).A; m[1] = (A{1})[0] {
+               return 1
+       }
+       return 0
+}

diff --git a/test/fixedbugs/bug465.dir/b.go b/test/fixedbugs/bug465.dir/b.go
new file mode 100644 (file)
index 0000000..0f4909f
--- /dev/null
+++ b/test/fixedbugs/bug465.dir/b.go
@@ -0,0 +1,17 @@
+// Copyright 2012 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 "./a"
+
+func main() {
+       for _, f := range []func() int{
+               a.F1, a.F2, a.F3, a.F4,
+               a.F5, a.F6, a.F7} {
+               if f() > 1 {
+                       panic("f() > 1")
+               }
+       }
+}

diff --git a/test/fixedbugs/bug465.go b/test/fixedbugs/bug465.go
new file mode 100644 (file)
index 0000000..a6ef587
--- /dev/null
+++ b/test/fixedbugs/bug465.go
@@ -0,0 +1,10 @@
+// rundir
+
+// Copyright 2012 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 4230: inlining bug for composite literal in
+// if, for, switch statements.
+
+package ignored