...
Run Format

Source file test/fixedbugs/issue4585.go

Documentation: test/fixedbugs

  // run
  
  // 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 4585: comparisons and hashes process blank
  // fields and padding in structs.
  
  package main
  
  import "unsafe"
  
  // T is a structure with padding.
  type T struct {
  	A     int16
  	B     int64
  	C     int16
  	D     int64
  	Dummy [64]byte
  }
  
  // U is a structure with a blank field
  type U struct {
  	A, _, B int
  	Dummy   [64]byte
  }
  
  // USmall is like U but the frontend will inline comparison
  // instead of calling the generated eq function.
  type USmall struct {
  	A, _, B int32
  }
  
  // V has padding but not on the first field.
  type V struct {
  	A1, A2, A3 int32
  	B          int16
  	C          int32
  }
  
  // W has padding at the end.
  type W struct {
  	A1, A2, A3 int32
  	B          int32
  	C          int8
  }
  
  func test1() {
  	var a, b U
  	m := make(map[U]int)
  	copy((*[16]byte)(unsafe.Pointer(&a))[:], "hello world!")
  	a.A, a.B = 1, 2
  	b.A, b.B = 1, 2
  	if a != b {
  		panic("broken equality: a != b")
  	}
  
  	m[a] = 1
  	m[b] = 2
  	if len(m) == 2 {
  		panic("broken hash: len(m) == 2")
  	}
  	if m[a] != 2 {
  		panic("m[a] != 2")
  	}
  }
  
  func test2() {
  	var a, b T
  	m := make(map[T]int)
  
  	copy((*[16]byte)(unsafe.Pointer(&a))[:], "hello world!")
  	a.A, a.B, a.C, a.D = 1, 2, 3, 4
  	b.A, b.B, b.C, b.D = 1, 2, 3, 4
  
  	if a != b {
  		panic("broken equality: a != b")
  	}
  
  	m[a] = 1
  	m[b] = 2
  	if len(m) == 2 {
  		panic("broken hash: len(m) == 2")
  	}
  	if m[a] != 2 {
  		panic("m[a] != 2")
  	}
  }
  
  func test3() {
  	var a, b USmall
  	copy((*[12]byte)(unsafe.Pointer(&a))[:], "hello world!")
  	a.A, a.B = 1, 2
  	b.A, b.B = 1, 2
  	if a != b {
  		panic("broken equality: a != b")
  	}
  }
  
  func test4() {
  	var a, b V
  	m := make(map[V]int)
  
  	copy((*[20]byte)(unsafe.Pointer(&a))[:], "Hello World, Gopher!")
  	a.A1, a.A2, a.A3, a.B, a.C = 1, 2, 3, 4, 5
  	b.A1, b.A2, b.A3, b.B, b.C = 1, 2, 3, 4, 5
  
  	if a != b {
  		panic("broken equality: a != b")
  	}
  
  	m[a] = 1
  	m[b] = 2
  	if len(m) == 2 {
  		panic("broken hash: len(m) == 2")
  	}
  	if m[a] != 2 {
  		panic("m[a] != 2")
  	}
  }
  
  func test5() {
  	var a, b W
  	m := make(map[W]int)
  
  	copy((*[20]byte)(unsafe.Pointer(&a))[:], "Hello World, Gopher!")
  	a.A1, a.A2, a.A3, a.B, a.C = 1, 2, 3, 4, 5
  	b.A1, b.A2, b.A3, b.B, b.C = 1, 2, 3, 4, 5
  
  	if a != b {
  		panic("broken equality: a != b")
  	}
  
  	m[a] = 1
  	m[b] = 2
  	if len(m) == 2 {
  		panic("broken hash: len(m) == 2")
  	}
  	if m[a] != 2 {
  		panic("m[a] != 2")
  	}
  }
  
  func main() {
  	test1()
  	test2()
  	test3()
  	test4()
  	test5()
  }
  

View as plain text