if !ok {
				t.Errorf("package %s: missing feature %q", fi.Name(), feature)
			}
			delete(w.features, feature)
		}

		for _, feature := range w.Features() {
			t.Errorf("package %s: extra feature not in golden file: %q", fi.Name(), feature)
		}
	}
}

func TestCompareAPI(t *testing.T) {
	tests := []struct {
		name                          string
		features, required, exception []string

name: Pkg.go.dev bugs or feature requests
description: Issues or feature requests for the documentation site
title: "x/pkgsite: issue title"
labels: ["pkgsite"]
body:
  - type: markdown
    attributes:
      value: "Please answer these questions before submitting your issue. Thanks!"
  - type: input
    id: url
    attributes:
      label: "What is the URL of the page with the issue?"
    validations:
      required: true
  - type: input

name: Go vulnerability management - bugs and feature requests
description: Issues or feature requests about Go vulnerability management
title: "x/vuln: issue title"
labels: ["vulncheck or vulndb"]
body:
  - type: markdown
    attributes:

/* An example of writing a C++ virtual function in Go.  */

%module(directors="1") callback

%{
#include <string>
#include "main.h"
%}

%include "std_string.i"

%feature("director");

Each file is a list of API features, one per line.

go1.txt (and similarly named files) are frozen once a version has been
shipped. Each file adds new lines but does not remove any.

except.txt lists features that may disappear without breaking true
compatibility.

Starting with go1.19.txt, each API feature line must end in "#nnnnn"

	sort.Strings(required)

	take := func(sl *[]string) string {
		s := (*sl)[0]
		*sl = (*sl)[1:]
		return s
	}

	for len(features) > 0 || len(required) > 0 {
		switch {
		case len(features) == 0 || (len(required) > 0 && required[0] < features[0]):
			feature := take(&required)
			if exceptionSet[feature] {
				// An "unfortunate" case: the feature was once
				// included in the API (e.g. go1.txt), but was

name: Gopls bugs or feature requests
description: Issues or feature requests for the Go language server (gopls)
title: "x/tools/gopls: issue title"
labels: ["gopls", "Tools"]
body:
  - type: markdown
    attributes:
      value: "Please answer these questions before submitting your issue. Thanks!"
  - type: input
    id: gopls-version
    attributes:
      label: "gopls version"
      description: "Output of `gopls -v version` on the command line"

pkg syscall (netbsd-386), const MAP_WIRED ideal-int
pkg syscall (netbsd-386), const MCL_CURRENT = 1
pkg syscall (netbsd-386), const MCL_CURRENT ideal-int
pkg syscall (netbsd-386), const MCL_FUTURE = 2
pkg syscall (netbsd-386), const MCL_FUTURE ideal-int
pkg syscall (netbsd-386), const MS_ASYNC = 1
pkg syscall (netbsd-386), const MS_ASYNC ideal-int
pkg syscall (netbsd-386), const MS_INVALIDATE = 2

	sel := (*n).(*ast.SelectorExpr)
	// For now, assume that the only instance of capital C is when
	// used as the imported package identifier.
	// The parser should take care of scoping in the future, so
	// that we will be able to distinguish a "top-level C" from a
	// local C.
	if l, ok := sel.X.(*ast.Ident); !ok || l.Name != "C" {
		return
	}
	if context == ctxAssign2 {
		context = ctxExpr
	}

needing to process arbitrary .o files. It only needs to process the .o
files generated from C files that cgo writes, and those are much more
limited in the ELF or other features that they use.

In essence, the _cgo_import.o file includes the extra linking
directives that cmd/link is not sophisticated enough to derive from _all.o
on its own. Similarly, the _all.o uses dynamic references to real