diff options
Diffstat (limited to 'src/cmd/api')
| -rw-r--r-- | src/cmd/api/goapi.go | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/src/cmd/api/goapi.go b/src/cmd/api/goapi.go index 9874b29292..01b17b8839 100644 --- a/src/cmd/api/goapi.go +++ b/src/cmd/api/goapi.go @@ -444,6 +444,11 @@ type listImports struct { var listCache sync.Map // map[string]listImports, keyed by contextName +// listSem is a semaphore restricting concurrent invocations of 'go list'. +var listSem = make(chan semToken, runtime.GOMAXPROCS(0)) + +type semToken struct{} + // loadImports populates w with information about the packages in the standard // library and the packages they themselves import in w's build context. // @@ -468,6 +473,9 @@ func (w *Walker) loadImports() { imports, ok := listCache.Load(name) if !ok { + listSem <- semToken{} + defer func() { <-listSem }() + cmd := exec.Command(goCmd(), "list", "-e", "-deps", "-json", "std") cmd.Env = listEnv(w.context) out, err := cmd.CombinedOutput() |