code review 7142052: cmd/gc: don't hash nor compare struct padding or blank ...

test/blank.go

 // run
 
 // Copyright 2009 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.
 
 // Test behavior of the blank identifier (_).
 
 package main
+
+import "unsafe"
 
 import _ "fmt"
 
 var call string
 
 type T struct {
         _, _, _ int
 }
 
 func (T) _() {
@@ skipping 75 matching lines @@
         }
 
         sum := 0
         for s := range ints {
                 sum += s
         }
         if sum != 3 {
                 panic(sum)
         }
 
+        type T1 struct{ x, y, z int }
+        t1 := *(*T)(unsafe.Pointer(&T1{1, 2, 3}))
+        t2 := *(*T)(unsafe.Pointer(&T1{4, 5, 6}))
+        if t1 != t2 {
+                panic("T{} != T{}")
+        }
+
         h(a, b)
-        
+
         m()
 }
 
 type I interface {
         M(_ int, y int)
 }
 
 type TI struct{}
 
 func (_ TI) M(x int, y int) {
         if x != y {
                 println("invalid M call:", x, y)
                 panic("bad M")
         }
 }
 
 var fp = func(_ int, y int) {}
 
 func init() {
         fp = fp1
 }
 
 func fp1(x, y int) {
         if x != y {
                 println("invalid fp1 call:", x, y)
                 panic("bad fp1")
         }
 }
 
-
 func m() {
         var i I
-        
+
         i = TI{}
         i.M(1, 1)
         i.M(2, 2)
-        
+
         fp(1, 1)
         fp(2, 2)
 }
 
 // useless but legal
 var _ int = 1
 var _ = 2
 var _, _ = 3, 4
 
 const _ = 3
 const _, _ = 4, 5
 
 type _ int
 
 func _() {
         panic("oops")
 }
 
 func ff() {
         var _ int = 1
 }
-