1 files changed, 7 insertions, 1 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoCompileActionBuilder.java b/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoCompileActionBuilder.java
index 374bf9b9fe..6fdcc040f0 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoCompileActionBuilder.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoCompileActionBuilder.java
@@ -530,7 +530,9 @@ public class ProtoCompileActionBuilder {
       ImmutableList<String> protocOpts) {
     CustomCommandLine.Builder cmdLine = CustomCommandLine.builder();
 
-    cmdLine.addAll(transitiveProtoPathFlags);
+    cmdLine.addAll(
+        VectorArg.of(transitiveProtoPathFlags)
+            .mapped(ProtoCompileActionBuilder::expandTransitiveProtoPathFlags));
 
     // A set to check if there are multiple invocations with the same name.
     HashSet<String> invocationNames = new HashSet<>();
@@ -604,6 +606,10 @@ public class ProtoCompileActionBuilder {
     }
   }
 
+  private static void expandTransitiveProtoPathFlags(String flag, Consumer<String> args) {
+    args.accept("--proto_path=" + flag);
+  }
+
   private static void expandTransitiveImportArg(Artifact artifact, Consumer<String> args) {
     args.accept("-I" + getPathIgnoringRepository(artifact) + "=" + artifact.getExecPathString());
   }