nocgo.go raw

   1  // SPDX-License-Identifier: Apache-2.0
   2  // SPDX-FileCopyrightText: 2022 The Ebitengine Authors
   3  
   4  //go:build !cgo && (darwin || freebsd || linux || netbsd)
   5  
   6  package purego
   7  
   8  // if CGO_ENABLED=0 import fakecgo to setup the Cgo runtime correctly.
   9  // This is required since some frameworks need TLS setup the C way which Go doesn't do.
  10  // We currently don't support ios in fakecgo mode so force Cgo or fail
  11  //
  12  // The way that the Cgo runtime (runtime/cgo) works is by setting some variables found
  13  // in runtime with non-null GCC compiled functions. The variables that are replaced are
  14  // var (
  15  //		iscgo             bool 							// in runtime/cgo.go
  16  //		_cgo_init         unsafe.Pointer 				// in runtime/cgo.go
  17  //		_cgo_thread_start unsafe.Pointer				// in runtime/cgo.go
  18  //		_cgo_notify_runtime_init_done unsafe.Pointer 	// in runtime/cgo.go
  19  //		_cgo_setenv unsafe.Pointer  					// in runtime/env_posix.go
  20  //		_cgo_unsetenv unsafe.Pointer					// in runtime/env_posix.go
  21  // )
  22  // importing fakecgo will set these (using //go:linkname) with functions written
  23  // entirely in Go (except for some assembly trampolines to change GCC ABI to Go ABI).
  24  // Doing so makes it possible to build applications that call into C without CGO_ENABLED=1.
  25  import _ "github.com/ebitengine/purego/internal/fakecgo"
  26