IDF release/v3.3 (#3672)

ESP-IDF release/v3.3: 66d3783c8
esp-face: 420fc7e
esp32-camera: 0107093

tools/sdk/include/lwip/netif/ppp/ppp.h

@@ -47,6 +47,10 @@
 #include "lwip/ip6_addr.h"
 #endif /* PPP_IPV6_SUPPORT */
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /* Disable non-working or rarely used PPP feature, so rarely that we don't want to bloat ppp_opts.h with them */
 #ifndef PPP_OPTIONS
 #define PPP_OPTIONS         0
@@ -685,6 +689,10 @@ err_t ppp_ioctl(ppp_pcb *pcb, u8_t cmd, void *arg);
 #define ppp_set_netif_linkcallback(ppp, link_cb)           \
         netif_set_link_callback(ppp->netif, link_cb);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* PPP_H */
 
 #endif /* PPP_SUPPORT */