issue4085b.go

     1  // run
     2  
     3  // Copyright 2013 The Go Authors. All rights reserved.
     4  // Use of this source code is governed by a BSD-style
     5  // license that can be found in the LICENSE file.
     6  
     7  package main
     8  
     9  import (
    10  	"strings"
    11  	"unsafe"
    12  )
    13  
    14  type T []int
    15  
    16  func main() {
    17  	n := -1
    18  	shouldPanic("len out of range", func() { _ = make(T, n) })
    19  	shouldPanic("cap out of range", func() { _ = make(T, 0, n) })
    20  	shouldPanic("len out of range", func() { _ = make(T, int64(n)) })
    21  	shouldPanic("cap out of range", func() { _ = make(T, 0, int64(n)) })
    22  	testMakeInAppend(n)
    23  
    24  	var t *byte
    25  	if unsafe.Sizeof(t) == 8 {
    26  		// Test mem > maxAlloc
    27  		var n2 int64 = 1 << 59
    28  		shouldPanic("len out of range", func() { _ = make(T, int(n2)) })
    29  		shouldPanic("cap out of range", func() { _ = make(T, 0, int(n2)) })
    30  		testMakeInAppend(int(n2))
    31  		// Test elem.size*cap overflow
    32  		n2 = 1<<63 - 1
    33  		shouldPanic("len out of range", func() { _ = make(T, int(n2)) })
    34  		shouldPanic("cap out of range", func() { _ = make(T, 0, int(n2)) })
    35  		testMakeInAppend(int(n2))
    36  		var x uint64 = 1<<64 - 1
    37  		shouldPanic("len out of range", func() { _ = make([]byte, x) })
    38  		shouldPanic("cap out of range", func() { _ = make(T, 0, x) })
    39  		testMakeInAppend(int(x))
    40  	} else {
    41  		n = 1<<31 - 1
    42  		shouldPanic("len out of range", func() { _ = make(T, n) })
    43  		shouldPanic("cap out of range", func() { _ = make(T, 0, n) })
    44  		shouldPanic("len out of range", func() { _ = make(T, int64(n)) })
    45  		shouldPanic("cap out of range", func() { _ = make(T, 0, int64(n)) })
    46  		testMakeInAppend(n)
    47  		var x uint64 = 1<<32 - 1
    48  		shouldPanic("len out of range", func() { _ = make([]byte, x) })
    49  		shouldPanic("cap out of range", func() { _ = make(T, 0, x) })
    50  		testMakeInAppend(int(x))
    51  	}
    52  }
    53  
    54  func shouldPanic(str string, f func()) {
    55  	defer func() {
    56  		err := recover()
    57  		if err == nil {
    58  			panic("did not panic")
    59  		}
    60  		s := err.(error).Error()
    61  		if !strings.Contains(s, str) {
    62  			panic("got panic " + s + ", want " + str)
    63  		}
    64  	}()
    65  
    66  	f()
    67  }
    68  
    69  // Test make in append panics since the gc compiler optimizes makes in appends.
    70  func testMakeInAppend(n int) {
    71  	lengths := []int{0, 1}
    72  	for _, length := range lengths {
    73  		t := make(T, length)
    74  		shouldPanic("len out of range", func() { _ = append(t, make(T, n)...) })
    75  		shouldPanic("cap out of range", func() { _ = append(t, make(T, 0, n)...) })
    76  		shouldPanic("len out of range", func() { _ = append(t, make(T, int64(n))...) })
    77  		shouldPanic("cap out of range", func() { _ = append(t, make(T, 0, int64(n))...) })
    78  		shouldPanic("len out of range", func() { _ = append(t, make(T, uint64(n))...) })
    79  		shouldPanic("cap out of range", func() { _ = append(t, make(T, 0, uint64(n))...) })
    80  		shouldPanic("len out of range", func() { _ = append(t, make(T, int(n))...) })
    81  		shouldPanic("cap out of range", func() { _ = append(t, make(T, 0, int(n))...) })
    82  		shouldPanic("len out of range", func() { _ = append(t, make(T, uint(n))...) })
    83  		shouldPanic("cap out of range", func() { _ = append(t, make(T, 0, uint(n))...) })
    84  	}
    85  }
    86
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