Restrict dynamic auto socket test to Linux

configure.ac

@@ -95,6 +95,19 @@ AC_MSG_RESULT([$os_freebsd])
 
 AM_CONDITIONAL([OS_FREEBSD], [test "x$os_freebsd" = "xyes"])
 
+# ==================== DETECT LINUX ====================
+AC_MSG_CHECKING([for Linux])
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+#ifndef __linux__
+#error "Not Linux"
+#endif
+]], [[ return 0; ]])],
+    [os_linux=yes],
+    [os_linux=no])
+AC_MSG_RESULT([$os_linux])
+
+AM_CONDITIONAL([OS_LINUX], [test "x$os_linux" = "xyes"])
+
 # Set TUN libs based on platform
 if test "x$os_windows" = "xyes"; then
     TUN_LIBS="-liphlpapi -lws2_32 -ladvapi32 -lbcrypt -ldbghelp"

tests/Makefile.am

@@ -101,8 +101,7 @@ check_PROGRAMS = \
 	bench_uasync_timeouts
 
 # Linux-only тест: требует root + dummy-интерфейсы + iproute2/netlink
-if OS_WINDOWS
-else
+if OS_LINUX
 check_PROGRAMS += test_auto_socket_dynamic
 endif