diff --git a/components/lwip/include/lwip/port/lwipopts.h b/components/lwip/include/lwip/port/lwipopts.h
index 8a94994c..2eb44513 100644
--- a/components/lwip/include/lwip/port/lwipopts.h
+++ b/components/lwip/include/lwip/port/lwipopts.h
@@ -46,6 +46,7 @@
 
 #include "sdkconfig.h"
 #include <stddef.h>
+#include <stdbool.h>
 #include "esp_libc.h"
 
 //#define SOCKETS_MT
@@ -193,7 +194,7 @@
 /**
  * Use DRAM instead of IRAM
  */
-extern void *pvPortMalloc( size_t xWantedSize, const char * file, unsigned line, unsigned char use_iram);
+extern void *pvPortMalloc( size_t xWantedSize, const char * file, unsigned line, bool use_iram);
 extern void *pvPortZalloc( size_t xWantedSize, const char * file, unsigned line);
 extern void *pvPortCalloc(size_t count, size_t size, const char * file, unsigned line);
 extern void vPortFree(void *pv, const char * file, unsigned line);