}

		BackTrace[i] = (PVOID)(ControlPc);
	}
	return i;
#else
	return 0;
#endif
}
*/
import "C"

import (
	"internal/testenv"
	"reflect"
	"runtime"
	"strings"
	"testing"
	"unsafe"
)

// Test that the stack can be unwound through a call out and call back
// into Go.
func testCallbackCallersSEH(t *testing.T) {
	testenv.SkipIfOptimizationOff(t) // This test requires inlining.

// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package cgotest

import _ "unsafe"

//go:linkname lockedOSThread runtime.lockedOSThread
//extern runtime_lockedOSThread

</pre>

<p>
The following built-in functions are not permitted in statement context:
</p>

<pre>
append cap complex imag len make new real
unsafe.Add unsafe.Alignof unsafe.Offsetof unsafe.Sizeof unsafe.Slice unsafe.SliceData unsafe.String unsafe.StringData
</pre>

<pre>
h(x+y)
f.Close()
&lt;-ch
(&lt;-ch)
len("foo")  // illegal if len is the built-in function
</pre>

}

//go:linkname runtime_arena_newArena
func runtime_arena_newArena() unsafe.Pointer

//go:linkname runtime_arena_arena_New
func runtime_arena_arena_New(arena unsafe.Pointer, typ any) any

// Mark as noescape to avoid escaping the slice header.
//
//go:noescape
//go:linkname runtime_arena_arena_Slice
func runtime_arena_arena_Slice(arena unsafe.Pointer, slice any, cap int)

//go:linkname runtime_arena_arena_Free

	// #include <stdio.h>
	// #include <stdlib.h>
	//
	// static void myprint(char* s) {
	//   printf("%s\n", s);
	// }
	import "C"
	import "unsafe"

	func main() {
		cs := C.CString("Hello from stdio")
		C.myprint(cs)
		C.free(unsafe.Pointer(cs))
	}

A few special functions convert between Go and C types
by making copies of the data. In pseudo-Go definitions:

	// Go string to C string

The [SliceAt(typ Type, p unsafe.Pointer, len int)] function
returns a Value representing a slice whose underlying array starts

	xCFNumberRef = C.CFNumberCreate(C.kCFAllocatorSystemDefault, C.kCFNumberSInt64Type, unsafe.Pointer(&v))
	//fmt.Printf("CFNumberRef: %x\n", uintptr(unsafe.Pointer(xCFNumberRef)))
}

var xCFNumberRef C.CFNumberRef

func testCFDateRef() {
	xCFDateRef = C.CFDateCreate(C.kCFAllocatorSystemDefault, 0) // 0 value is 1 Jan 2001 00:00:00 GMT
	//fmt.Printf("CFDateRef: %x\n", uintptr(unsafe.Pointer(xCFDateRef)))
}

var xCFDateRef C.CFDateRef

// rewriteUnsafe returns a version of t with references to unsafe.Pointer
// rewritten to use _cgo_unsafe.Pointer instead.
func (p *Package) rewriteUnsafe(t ast.Expr) ast.Expr {
	switch t := t.(type) {
	case *ast.Ident:
		// We don't see a SelectorExpr for unsafe.Pointer;
		// this is created by code in this file.
		if t.Name == "unsafe.Pointer" {
			return ast.NewIdent("_cgo_unsafe.Pointer")
		}
	case *ast.ArrayType:

func (tw *Writer) WriteHeader(hdr *Header) error {
	if err := tw.Flush(); err != nil {
		return err
	}
	tw.hdr = *hdr // Shallow copy of Header

	// Avoid usage of the legacy TypeRegA flag, and automatically promote
	// it to use TypeReg or TypeDir.
	if tw.hdr.Typeflag == TypeRegA {
		if strings.HasSuffix(tw.hdr.Name, "/") {
			tw.hdr.Typeflag = TypeDir
		} else {

				if s, ok := spec.(*ast.ImportSpec); ok && s.Path.Value == `"C"` {
					// Replace "C" with _ "unsafe", to keep program valid.
					// (Deleting import statement or clause is not safe if it is followed
					// in the source by an explicit semicolon.)
					f.Edit.Replace(f.offset(s.Path.Pos()), f.offset(s.Path.End()), `_ "unsafe"`)
				}
			}
		}
	}

	// Accumulate pointers to uses of C.x.
	if f.Ref == nil {