cmd/go: runtime and runtime/internal packages depend on runtime/internal/sys

Fixes #13655.

Change-Id: I764019aecdd59743baa436b7339499e6c2126268
Reviewed-on: https://go-review.googlesource.com/17916
Run-TryBot: Ian Lance Taylor <[email protected]>
Reviewed-by: Russ Cox <[email protected]>

Author: ianlancetaylor

src/cmd/go/go_test.go

@@ -2454,3 +2454,12 @@ func TestGoBuildARM(t *testing.T) {
 	tg.run("build", "hello.go")
 	tg.grepStderrNot("unable to find math.a", "did not build math.a correctly")
 }
+
+func TestIssue13655(t *testing.T) {
+	tg := testgo(t)
+	defer tg.cleanup()
+	for _, pkg := range []string{"runtime", "runtime/internal/atomic"} {
+		tg.run("list", "-f", "{{.Deps}}", pkg)
+		tg.grepStdout("runtime/internal/sys", "did not find required dependency of "+pkg+" on runtime/internal/sys")
+	}
+}

src/cmd/go/pkg.go

@@ -835,6 +835,14 @@ func (p *Package) load(stk *importStack, bp *build.Package, err error) *Package
 		}
 	}
 
+	// Runtime and its internal packages depend on runtime/internal/sys,
+	// so that they pick up the generated zversion.go file.
+	// This can be an issue particularly for runtime/internal/atomic;
+	// see issue 13655.
+	if p.Standard && (p.ImportPath == "runtime" || strings.HasPrefix(p.ImportPath, "runtime/internal/")) && p.ImportPath != "runtime/internal/sys" {
+		importPaths = append(importPaths, "runtime/internal/sys")
+	}
+
 	// Build list of full paths to all Go files in the package,
 	// for use by commands like go fmt.
 	p.gofiles = stringList(p.GoFiles, p.CgoFiles, p.TestGoFiles, p.XTestGoFiles)