--- /dev/null
+++ Libc/Libc-1725.40.4/tests/err.c
@@ -0,0 +1,25 @@
+#include <Block.h>
+#include <darwintest.h>
+#include <err.h>
+
+#define ITERATIONS 100
+
+T_DECL(err_multiple_exit_b, "Repeated set exit blocks doesn't leak copied blocks")
+{
+	int __block num = 0;
+	for (int i = 0; i < ITERATIONS; ++i) {
+		err_set_exit_b(^(int j) { num += j; });
+	}
+	err_set_exit_b(NULL);
+	// Dummy expect is necessary to run leaks on this test.
+	T_EXPECT_NULL(NULL, "DUMMY EXPECT");
+}
+
+T_DECL(err_multiple_exit, "Setting exit w/o block after setting exit with block doesn't leak copied block")
+{
+	int __block num = 0;
+	err_set_exit_b(^(int j) { num += j; });
+	err_set_exit(NULL);
+	// Dummy expect is necessary to run leaks on this test.
+	T_EXPECT_NULL(NULL, "DUMMY EXPECT");
+}