[release-branch.go1.13] cmd/go/internal/modget: synchronize writes to modOnly map...

Updates #35317
Fixes #35318

Change-Id: Id858a25dc16a1bbff1802d25bcd4aca31c1133bc
Reviewed-on: https://go-review.googlesource.com/c/go/+/205067
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>
(cherry picked from commit 7e71c9c3edbf5b7a8608d6f739c20420a618e0ab)
Reviewed-on: https://go-review.googlesource.com/c/go/+/205517

diff --git a/src/cmd/go/internal/modget/get.go b/src/cmd/go/internal/modget/get.go
index 1cae311c4c157b825164f2fe36fbd559fe2ebeeb..d234a1eb0b99603f390851e9129342335ba85436 100644 (file)
--- a/src/cmd/go/internal/modget/get.go
+++ b/src/cmd/go/internal/modget/get.go
@@ -452,6 +452,7 @@ func runGet(cmd *base.Command, args []string) {
        // This includes explicitly requested modules that don't have a root package
        // and modules with a target version of "none".
        var wg sync.WaitGroup
+       var modOnlyMu sync.Mutex
        modOnly := make(map[string]*query)
        for _, q := range queries {
                if q.m.Version == "none" {
@@ -464,7 +465,9 @@ func runGet(cmd *base.Command, args []string) {
                                if hasPkg, err := modload.ModuleHasRootPackage(q.m); err != nil {
                                        base.Errorf("go get: %v", err)
                                } else if !hasPkg {
+                                       modOnlyMu.Lock()
                                        modOnly[q.m.Path] = q
+                                       modOnlyMu.Unlock()
                                }
                                wg.Done()
                        }(q)

diff --git a/src/cmd/go/testdata/script/mod_issue35317.txt b/src/cmd/go/testdata/script/mod_issue35317.txt
new file mode 100644 (file)
index 0000000..003390b
--- /dev/null
+++ b/src/cmd/go/testdata/script/mod_issue35317.txt
@@ -0,0 +1,8 @@
+# Regression test for golang.org/issue/35317:
+# 'go get' with multiple module-only arguments was racy.
+
+env GO111MODULE=on
+[short] skip
+
+go mod init example.com
+go get golang.org/x/text@v0.3.0 golang.org/x/internal@v0.1.0