Change inline to static inline functions. Ref Github issue 62.

components/freertos/include/freertos/portable.h

@@ -192,7 +192,7 @@ void vPortEndScheduler( void ) PRIVILEGED_FUNCTION;
 #endif
 
 /* Multi-core: get current core ID */
-inline uint32_t xPortGetCoreID() {
+static inline uint32_t xPortGetCoreID() {
     int id;
     asm volatile(
         "rsr.prid %0\n"

components/freertos/include/freertos/portmacro.h

@@ -234,7 +234,7 @@ static inline unsigned portENTER_CRITICAL_NESTED() { unsigned state = XTOS_SET_I
  * *bitwise inverse* of the old mem if the mem wasn't written. This doesn't seem to happen on the
  * ESP32, though. (Would show up directly if it did because the magic wouldn't match.)
  */
-inline void uxPortCompareSet(volatile uint32_t *addr, uint32_t compare, uint32_t *set) {
+static inline void uxPortCompareSet(volatile uint32_t *addr, uint32_t compare, uint32_t *set) {
     __asm__ __volatile__(
         "WSR 	    %2,SCOMPARE1 \n"
         "ISYNC      \n"