diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ProcessPackageDirectory.java b/src/main/java/com/google/devtools/build/lib/skyframe/ProcessPackageDirectory.java
index d6c5ff03cb0219..349aec4b15b740 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ProcessPackageDirectory.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/ProcessPackageDirectory.java
@@ -16,6 +16,7 @@
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.devtools.build.lib.analysis.BlazeDirectories;
+import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.cmdline.PackageIdentifier;
 import com.google.devtools.build.lib.cmdline.RepositoryName;
 import com.google.devtools.build.lib.events.Event;
@@ -197,6 +198,10 @@ private Iterable<SkyKey> getSubdirDeps(
           && PathPackageLocator.DEFAULT_TOP_LEVEL_EXCLUDES.contains(basename)) {
         continue;
       }
+      if (basename.equals(Label.EXTERNAL_PACKAGE_NAME.getPathString())) {
+        // Not a real package.
+        continue;
+      }
       PathFragment subdirectory = rootRelativePath.getRelative(basename);
 
       // If this subdirectory is one of the excluded paths, don't recurse into it.
diff --git a/src/test/shell/bazel/empty_package.sh b/src/test/shell/bazel/empty_package.sh
index d6476522de2014..867fb0150287c8 100755
--- a/src/test/shell/bazel/empty_package.sh
+++ b/src/test/shell/bazel/empty_package.sh
@@ -44,4 +44,17 @@ EOF
   expect_log "SCREEEECH"
 }
 
+function test_empty_external() {
+  mkdir foo
+  cd foo
+  touch WORKSPACE
+  # Create a dummy BUILD file, otherwise `bazel build` will complain that there
+  # were no targets to build.
+  cat > BUILD <<EOF
+exports_files(["BUILD"])
+EOF
+  mkdir external
+  bazel build ... &> $TEST_log || fail "Failed to build ..."
+}
+
 run_suite "empty package tests"