dl: add dynamic load module

vlib/dl/dl_test.v

@@ -0,0 +1,28 @@
+import dl
+
+fn test_dl() {
+	$if linux {
+		run_test_linux()
+		return
+	}
+	$if windows {
+		run_test_windows()
+		return
+	} $else {
+		eprint('currently not implemented on this platform')
+	}
+}
+
+fn run_test_linux() {
+	// ensure a not-existing dl won't be loaded
+	h := dl.open('not-existing-dynamic-link-library', dl.RTLD_NOW)
+	// println('handle = $h')
+	assert h == 0
+}
+
+fn run_test_windows() {
+	// ensure a not-existing dl won't be loaded
+	h := dl.open('not-existing-dynamic-link-library', dl.RTLD_NOW)
+	// println('handle = $h')
+	assert h == 0
+}