diff --git a/regenerate_stale_files.sh b/regenerate_stale_files.sh
index c96693ac10..eaff025e8d 100755
--- a/regenerate_stale_files.sh
+++ b/regenerate_stale_files.sh
@@ -12,13 +12,21 @@ cd $(dirname -- "$0")
 
 readonly BazelBin="${BAZEL:-bazel} ${BAZEL_STARTUP_FLAGS}"
 
+STALENESS_TESTS=(
+  "src:cmake_lists_staleness_test"
+  "src/google/protobuf:well_known_types_staleness_test"
+  "objectivec:well_known_types_staleness_test"
+  "php:test_amalgamation_staleness"
+  "ruby/ext/google/protobuf_c:test_amalgamation_staleness"
+  "upb/cmake:test_generated_files"
+  "upb/upb_generator:plugin_upb_proto_staleness_test"
+  "upb/reflection:descriptor_upb_proto_staleness_test"
+)
+
 # Run and fix all staleness tests.
-${BazelBin} test src:cmake_lists_staleness_test "$@" || ./bazel-bin/src/cmake_lists_staleness_test --fix
-${BazelBin} test src/google/protobuf:well_known_types_staleness_test "$@" || ./bazel-bin/src/google/protobuf/well_known_types_staleness_test --fix
-${BazelBin} test objectivec:well_known_types_staleness_test "$@" || ./bazel-bin/objectivec/well_known_types_staleness_test --fix
-${BazelBin} test php:test_amalgamation_staleness "$@" || ./bazel-bin/php/test_amalgamation_staleness --fix
-${BazelBin} test ruby/ext/google/protobuf_c:test_amalgamation_staleness "$@" || ./bazel-bin/ruby/ext/google/protobuf_c/test_amalgamation_staleness --fix
-${BazelBin} test upb/cmake:test_generated_files "$@" || ./bazel-bin/upb/cmake/test_generated_files --fix
+for test in $STALENESS_TESTS; do
+  ${BazelBin} test $test "$@" || ./bazel-bin/${test%%:*}/${test#*:} --fix
+done
 
 # Generate C# code.
 # This doesn't currently have Bazel staleness tests, but there's an existing
diff --git a/upb_generator/bootstrap_compiler.bzl b/upb_generator/bootstrap_compiler.bzl
index a1d8671153..1c3f3ee7b4 100644
--- a/upb_generator/bootstrap_compiler.bzl
+++ b/upb_generator/bootstrap_compiler.bzl
@@ -50,7 +50,7 @@ def _generated_srcs_for_suffix(prefix, srcs, suffix):
 def _generated_srcs_for_generator(prefix, srcs, generator):
     ret = _generated_srcs_for_suffix(prefix, srcs, ".{}.h".format(generator))
 
-    if not (generator == "upb" and prefix.endswith("stage1")):
+    if generator != "upb" or prefix.endswith("stage0"):
         ret += _generated_srcs_for_suffix(prefix, srcs, ".{}.c".format(generator))
     return ret
 
@@ -72,7 +72,7 @@ def _stage0_proto_staleness_test(name, base_dir, src_files, src_rules, strip_pre
     )
 
     staleness_test(
-        name = name + "_staleness_test",
+        name = name + "_stage0_staleness_test",
         outs = _generated_srcs(base_dir + "stage0", src_files),
         generated_pattern = "bootstrap_generated_sources/%s",
         target_files = native.glob([base_dir + "stage0/**"]),
@@ -101,6 +101,26 @@ def _generate_stage1_proto(name, base_dir, src_files, src_rules, generator, kwar
         **kwargs
     )
 
+# begin:github_only
+def _cmake_staleness_test(name, base_dir, src_files):
+    # Copy the final gencode for staleness comparison
+    native.genrule(
+        name = name + "_copy_gencode",
+        outs = _generated_srcs("generated_sources/cmake" + base_dir, src_files),
+        srcs = [name],
+        cmd = "for src in $(SRCS); do cp -f $$src $(@D); done",
+    )
+
+    # Keep bazel gencode in sync with our checked-in sources needed for cmake builds.
+    staleness_test(
+        name = name + "_staleness_test",
+        outs = _generated_srcs("cmake" + base_dir, src_files),
+        generated_pattern = "generated_sources/%s",
+        tags = ["manual"],
+    )
+
+# end:github_only
+
 def bootstrap_upb_proto_library(
         name,
         base_dir,
@@ -187,3 +207,8 @@ def bootstrap_upb_proto_library(
         visibility = visibility,
         **kwargs
     )
+
+    # begin:github_only
+    _cmake_staleness_test(name, base_dir, src_files)
+
+# end:github_only