diff --git a/tests/lib/c_lib/src/test_signal_decl.c b/tests/lib/c_lib/src/test_signal_decl.c
new file mode 100644
index 000000000000000..fa9490f911df5d9
--- /dev/null
+++ b/tests/lib/c_lib/src/test_signal_decl.c
@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2023 Meta
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <signal.h>
+
+#include <zephyr/ztest.h>
+
+ZTEST(test_c_lib, test_signal_decl)
+{
+	/*
+	 * Even though the use of the ANSI-C function "signal()" is not yet
+	 * supported in Zephyr, some users depend on it being declared (i.e.
+	 * without CONFIG_POSIX_API=y and with with CONFIG_POSIX_SIGNAL=n).
+	 */
+
+	zassert_not_null(signal);
+}