diff --git a/package/quagga/quagga.mk b/package/quagga/quagga.mk
index 420d72c79d..8aa58aceef 100644
--- a/package/quagga/quagga.mk
+++ b/package/quagga/quagga.mk
@@ -18,6 +18,11 @@ QUAGGA_CONF_OPTS = \
 	--sysconfdir=/etc/quagga \
 	--localstatedir=/var/run/quagga
 
+# quagga has its own internal copy of getopt_long. To avoid conflicts with libc's
+# getopt, we need to make sure that the getopt function itself is also built.
+QUAGGA_CONF_ENV = \
+	CFLAGS="$(TARGET_CFLAGS) -DREALLY_NEED_PLAIN_GETOPT"
+
 ifeq ($(BR2_PACKAGE_LIBCAP),y)
 QUAGGA_CONF_OPTS += --enable-capabilities
 QUAGGA_DEPENDENCIES += libcap