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38 lines
637 B
38 lines
637 B
4 months ago
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// run
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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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// Interface
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type I interface { F() int }
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// Implements interface
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type S struct { }
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func (s *S) F() int { return 1 }
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// Allocates S but returns I
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// Arg is unused but important:
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// if you take it out (and the 0s below)
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// then the bug goes away.
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func NewI(i int) I {
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return new(S)
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}
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// Uses interface method.
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func Use(x I) {
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x.F()
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}
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func main() {
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i := NewI(0);
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Use(i);
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// Again, without temporary
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// Crashes because x.F is 0.
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Use(NewI(0));
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}
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