diff --git a/src/test/util/setup_common.h b/src/test/util/setup_common.h
--- a/src/test/util/setup_common.h
+++ b/src/test/util/setup_common.h
@@ -44,7 +44,7 @@
  * that thread_local is supported on all architectures we support) or a
  * per-thread instance could be used in the multi-threaded test.
  */
-extern FastRandomContext g_insecure_rand_ctx;
+thread_local extern FastRandomContext g_insecure_rand_ctx;
 
 /**
  * Flag to make GetRand in random.h return the same number
diff --git a/src/test/util/setup_common.cpp b/src/test/util/setup_common.cpp
--- a/src/test/util/setup_common.cpp
+++ b/src/test/util/setup_common.cpp
@@ -41,7 +41,7 @@
 
 const std::function<std::string(const char *)> G_TRANSLATION_FUN = nullptr;
 
-FastRandomContext g_insecure_rand_ctx;
+thread_local FastRandomContext g_insecure_rand_ctx;
 
 std::ostream &operator<<(std::ostream &os, const uint256 &num) {
     os << num.ToString();