diff --git a/tests/stdlib/trlocks.nim b/tests/stdlib/trlocks.nim
new file mode 100644
index 0000000000..135d9b0282
--- /dev/null
+++ b/tests/stdlib/trlocks.nim
@@ -0,0 +1,14 @@
+discard """
+  action: "compile"
+  # Disallow joining to ensure it can compile in isolation.
+  # See #15584
+  joinable: false
+  cmd: "nim $target --threads:on $options $file"
+"""
+
+# bugfix #15584
+
+import rlocks
+
+var r: RLock
+r.initRLock()
diff --git a/tests/stdlib/tuserlocks.nim b/tests/stdlib/tuserlocks.nim
new file mode 100644
index 0000000000..f6eafa05d2
--- /dev/null
+++ b/tests/stdlib/tuserlocks.nim
@@ -0,0 +1,13 @@
+discard """
+  cmd: "nim $target --threads:on $options $file"
+"""
+
+import rlocks
+
+var r: RLock
+r.initRLock()
+doAssert r.tryAcquire()
+doAssert r.tryAcquire()
+r.release()
+r.release()
+r.deinitRLock()