handling, at some cost in run time, is available by setting
GOEXPERIMENT=cgocheck2 at build time.

It is possible to defeat this enforcement by using the unsafe package,
and of course there is nothing stopping the C code from doing anything
it likes. However, programs that break these rules are likely to fail
in unexpected and unpredictable ways.

The runtime/cgo.Handle type can be used to safely pass Go values

For the remaining programs,
we define a new GODEBUG setting that
allows individual programs to opt back in to the old behavior.
A GODEBUG setting may not be added if doing so is infeasible,
but that should be extremely rare.

GODEBUG settings added for compatibility will be maintained
for a minimum of two years (four Go releases).
Some, such as `http2client` and `http2server`,

	if x, ok := x.(*ast.Ident); ok {
		if f.isMangledName(x.Name) {
			error_(x.Pos(), "identifier %q may conflict with identifiers generated by cgo", x.Name)
		}
	}
}

// Save various references we are going to need later.
func (f *File) saveExprs(x interface{}, context astContext) {
	switch x := x.(type) {
	case *ast.Expr:
		switch (*x).(type) {
		case *ast.SelectorExpr:
			f.saveRef(x, context)
		}

		}
	})
}

// Test that the stack can be unwound through a call out and call back
// into Go.
func testCallbackCallers(t *testing.T) {
	if runtime.Compiler != "gc" {
		// The exact function names are not going to be the same.
		t.Skip("skipping for non-gc toolchain")
	}
	pc := make([]uintptr, 100)
	n := 0
	name := []string{
		"runtime.cgocallbackg1",
		"runtime.cgocallbackg",
		"runtime.cgocallback",

		err:  ErrHeader,
	}, {
		// BSD tar v3.1.2 rejects a PAX path with NUL in the value, while
		// GNU tar v1.27.1 simply truncates at first NUL.
		// We emulate the behavior of BSD since it is strange doing NUL
		// truncations since PAX records are length-prefix strings instead
		// of NUL-terminated C-strings.
		file: "testdata/pax-nul-path.tar",
		err:  ErrHeader,
	}, {
		file: "testdata/neg-size.tar",

It implements these forms as multiple instructions, often using the <code>R11</code> register
to hold temporary values.
Hand-written assembly can use <code>R11</code>, but doing so requires
being sure that the linker is not also using it to implement any of the other
instructions in the function.
</p>

<p>
When defining a <code>TEXT</code>, specifying frame size <code>$-4</code>

	// The start index is inclusive and the end index is exclusive.
	type span struct {
		start int
		end   int
	}
	spans := make([]span, 0, 32)

	// Find the field start and end indices.
	// Doing this in a separate pass (rather than slicing the string s
	// and collecting the result substrings right away) is significantly
	// more efficient, possibly due to cache effects.
	start := -1 // valid span start if >= 0

	//            _cgo0 := p
	//            _cgoCheckPointer(_cgo0, nil)
	//            C.f(_cgo0)
	//    }()
	// Using a function literal like this lets us evaluate the
	// function arguments only once while doing pointer checks.
	// This is particularly useful when passing additional arguments
	// to _cgoCheckPointer, as done in checkIndex and checkAddr.
	//
	// When the function argument is a conversion to unsafe.Pointer,

Unlike many projects on GitHub, the Go project does not use its bug tracker for general discussion or asking questions.
We only use our bug tracker for tracking bugs and tracking proposals going through the [Proposal Process](https://go.dev/s/proposal-process).

For asking questions, see:

* [The golang-nuts mailing list](https://groups.google.com/d/forum/golang-nuts)

* [The Go Forum](https://forum.golangbridge.org/), a web-based forum

			}
		}
	}

	// Apply overrides.
	for old, new := range override {
		if id := goIdent[old]; id != nil {
			id.Name = new
		}
	}

	// Any names still using the _C syntax are not going to compile,
	// although in general we don't know whether they all made it
	// into the file, so we can't warn here.
	//
	// The most common case is union types, which begin with