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2c2770c3d4
Fixes #10303. Change-Id: Ia68d3566ba3ebeea6e18e388446bd9b8c431e156 Reviewed-on: https://go-review.googlesource.com/10814 Reviewed-by: Ian Lance Taylor <iant@golang.org>
51 lines
1.9 KiB
Go
51 lines
1.9 KiB
Go
// Copyright 2014 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 runtime
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import "unsafe"
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//go:cgo_export_static main
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// Filled in by runtime/cgo when linked into binary.
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//go:linkname _cgo_init _cgo_init
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//go:linkname _cgo_malloc _cgo_malloc
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//go:linkname _cgo_free _cgo_free
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//go:linkname _cgo_thread_start _cgo_thread_start
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//go:linkname _cgo_sys_thread_create _cgo_sys_thread_create
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//go:linkname _cgo_notify_runtime_init_done _cgo_notify_runtime_init_done
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var (
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_cgo_init unsafe.Pointer
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_cgo_malloc unsafe.Pointer
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_cgo_free unsafe.Pointer
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_cgo_thread_start unsafe.Pointer
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_cgo_sys_thread_create unsafe.Pointer
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_cgo_notify_runtime_init_done unsafe.Pointer
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)
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// iscgo is set to true by the runtime/cgo package
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var iscgo bool
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// cgoHasExtraM is set on startup when an extra M is created for cgo.
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// The extra M must be created before any C/C++ code calls cgocallback.
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var cgoHasExtraM bool
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// cgoUse is called by cgo-generated code (using go:linkname to get at
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// an unexported name). The calls serve two purposes:
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// 1) they are opaque to escape analysis, so the argument is considered to
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// escape to the heap.
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// 2) they keep the argument alive until the call site; the call is emitted after
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// the end of the (presumed) use of the argument by C.
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// cgoUse should not actually be called (see cgoAlwaysFalse).
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func cgoUse(interface{}) { throw("cgoUse should not be called") }
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// cgoAlwaysFalse is a boolean value that is always false.
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// The cgo-generated code says if cgoAlwaysFalse { cgoUse(p) }.
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// The compiler cannot see that cgoAlwaysFalse is always false,
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// so it emits the test and keeps the call, giving the desired
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// escape analysis result. The test is cheaper than the call.
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var cgoAlwaysFalse bool
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