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Change-Id: Ie084691584b08e17944079f182cc353a98191780

Author: qiulaidongfeng

src/os/exec/exec.go

@@ -333,9 +333,9 @@ type Cmd struct {
 	// and https://go.dev/issue/43724 for more context.
 	lookPathErr error
 
-	// calledLookExtensions indicates whether
-	// lookExtensions has been called in Cmd.Command.
-	calledLookExtensions bool
+	// cacheLookExtensions cache the result of calling lookExtensions,
+	// use it only on windows.
+	cacheLookExtensions string
 }
 
 // A ctxResult reports the result of watching the Context associated with a
@@ -440,11 +440,8 @@ func Command(name string, arg ...string) *Cmd {
 		// Note that we cannot add an extension here for relative paths, because
 		// cmd.Dir may be set after we return from this function and that may cause
 		// the command to resolve to a different extension.
-		cmd.calledLookExtensions = true
 		lp, err := lookExtensions(name, "")
-		if lp != "" {
-			cmd.Path = lp
-		}
+		cmd.cacheLookExtensions = lp
 		if err != nil {
 			cmd.Err = err
 		}
@@ -646,7 +643,10 @@ func (c *Cmd) Start() error {
 		return c.Err
 	}
 	lp := c.Path
-	if runtime.GOOS == "windows" && !c.calledLookExtensions {
+	if c.cacheLookExtensions == "" {
+		lp = c.cacheLookExtensions
+	}
+	if runtime.GOOS == "windows" && c.cacheLookExtensions == "" {
 		// If c.Path is relative, we had to wait until now
 		// to resolve it in case c.Dir was changed.
 		// (If it is absolute, we already resolved its extension in Command