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bf5c0c957c
needs to dereference the base pointer to make sure it catches nil. R=r,ken DELTA=21 (21 added, 0 deleted, 0 changed) OCL=30083 CL=30101
26 lines
693 B
Go
26 lines
693 B
Go
// $G $D/$F.go && $L $F.$A && (! ./$A.out || echo BUG: should fail)
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// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package main
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import "unsafe"
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var x byte
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func main() {
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var p *[1<<30]byte = nil;
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x = 123;
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// The problem here is not the use of unsafe:
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// it is that indexing into p[] with a large
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// enough index jumps out of the unmapped section
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// at the beginning of memory and into valid memory.
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// Pointer offsets and array indices, if they are
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// very large, need to dereference the base pointer
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// to trigger a trap.
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println(p[uintptr(unsafe.Pointer(&x))]);
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}
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