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39 lines
1.2 KiB
Go
39 lines
1.2 KiB
Go
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// Copyright 2018 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 b
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import "./a"
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type T struct{ a.T }
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func (T) m() { println("ok") }
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// The compiler used to not pay attention to package for non-exported
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// methods when statically constructing itabs. The consequence of this
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// was that the call to b.F1(b.T{}) in c.go would create an itab using
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// a.T.m instead of b.T.m.
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func F1(i interface{ m() }) { i.m() }
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// The interface method calling convention depends on interface method
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// sets being sorted in the same order across compilation units. In
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// the test case below, at the call to b.F2(b.T{}) in c.go, the
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// interface method set is sorted as { a.m(); b.m() }.
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//
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// However, while compiling package b, its package path is set to "",
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// so the code produced for F2 uses { b.m(); a.m() } as the method set
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// order. So again, it ends up calling the wrong method.
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//
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// Also, this function is marked noinline because it's critical to the
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// test that the interface method call happen in this compilation
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// unit, and the itab construction happens in c.go.
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//
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//go:noinline
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func F2(i interface {
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m()
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a.I // embeds m() from package a
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}) {
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i.m()
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}
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