})
	// The first call will skip t with a nice message. On later calls, we just skip.
	if !haveSwig {
		t.Skip("swig not found")
	}
}

func mustHaveSwigOnce(t *testing.T) {
	swig, err := exec.LookPath("swig")
	if err != nil {
		t.Skipf("swig not in PATH: %s", err)
	}

	// Check that swig was installed with Go support by checking
	// that a go directory exists inside the swiglib directory.

// license that can be found in the LICENSE file.

//go:build gc

#include "_cgo_export.h"
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

/* Test calling panic from C.  This is what SWIG does.  */

extern void crosscall2(void (*fn)(void *, int), void *, int);
extern void _cgo_panic(void *, int);
extern void _cgo_allocate(void *, int);

void
callPanic(void)
{
	struct { const char *p; } a;

	library. To get the dependency without importing any specific
	symbols, use _ for local and remote.

	Example:
	//go:cgo_import_dynamic _ _ "libc.so.6"

	For compatibility with current versions of SWIG,
	#pragma dynimport is an alias for //go:cgo_import_dynamic.

//go:cgo_dynamic_linker "<path>"

	In internal linking mode, use "<path>" as the dynamic linker

/* Copyright 2011 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.  */

/* A trivial example of wrapping a C library using SWIG.  */

%{
#include <stdio.h>
#include <stdlib.h>
%}

%typemap(gotype) const char * "string"
%typemap(in) const char * %{
	$1 = malloc($input.n + 1);
	memcpy($1, $input.p, $input.n);
	$1[$input.n] = '\0';
%}

// license that can be found in the LICENSE file.

//go:build gccgo

#include "_cgo_export.h"
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

/* Test calling panic from C.  This is what SWIG does.  */

extern void _cgo_panic(const char *);
extern void *_cgo_allocate(size_t);

void
callPanic(void)
{
	_cgo_panic("panic from C");

// Copyright 2017 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.

// This file is here just to cause problems.
// main.swig turns into a file also named main.go.
// Make sure cmd/go keeps them separate
// when both are passed to cgo.

package main

//int F(void) { return 1; }
import "C"
import (
	"fmt"
	"os"
)