diff --git a/sandboxed_api/sandbox2/stack-trace.h b/sandboxed_api/sandbox2/stack-trace.h
index d28a979..d6b8046 100644
--- a/sandboxed_api/sandbox2/stack-trace.h
+++ b/sandboxed_api/sandbox2/stack-trace.h
@@ -24,15 +24,11 @@
 #include <memory>
 #include <string>
 
-#include "sandboxed_api/util/flag.h"
 #include "sandboxed_api/sandbox2/mounts.h"
 #include "sandboxed_api/sandbox2/policy.h"
 #include "sandboxed_api/sandbox2/regs.h"
 #include "sandboxed_api/sandbox2/unwind/unwind.pb.h"
 
-// Exposed for testing only
-ABSL_DECLARE_FLAG(bool, sandbox_libunwind_crash_handler);
-
 namespace sandbox2 {
 
 // Maximum depth of analyzed call stack.
diff --git a/sandboxed_api/sandbox2/stack-trace_test.cc b/sandboxed_api/sandbox2/stack-trace_test.cc
index b36e842..4609bc6 100644
--- a/sandboxed_api/sandbox2/stack-trace_test.cc
+++ b/sandboxed_api/sandbox2/stack-trace_test.cc
@@ -36,6 +36,8 @@
 #include "sandboxed_api/sandbox2/util/temp_file.h"
 #include "sandboxed_api/util/status_matchers.h"
 
+ABSL_DECLARE_FLAG(bool, sandbox_libunwind_crash_handler);
+
 using ::testing::Eq;
 using ::testing::HasSubstr;
 using ::testing::Not;