diff --git a/hal/include/HAL/Threads.h b/hal/include/HAL/Threads.h
index 4036d41fb5..8fe5578d4b 100644
--- a/hal/include/HAL/Threads.h
+++ b/hal/include/HAL/Threads.h
@@ -17,6 +17,7 @@
 #define NativeThreadHandle const pthread_t*
 #endif
 
+extern "C" {
 int32_t HAL_GetThreadPriority(NativeThreadHandle handle, HAL_Bool* isRealTime,
                               int32_t* status);
 int32_t HAL_GetCurrentThreadPriority(HAL_Bool* isRealTime, int32_t* status);
@@ -24,3 +25,4 @@ HAL_Bool HAL_SetThreadPriority(NativeThreadHandle handle, HAL_Bool realTime,
                                int32_t priority, int32_t* status);
 HAL_Bool HAL_SetCurrentThreadPriority(HAL_Bool realTime, int32_t priority,
                                       int32_t* status);
+}
diff --git a/hal/lib/athena/Threads.cpp b/hal/lib/athena/Threads.cpp
index f341b521af..8e8bc896ca 100644
--- a/hal/lib/athena/Threads.cpp
+++ b/hal/lib/athena/Threads.cpp
@@ -12,6 +12,7 @@
 
 #include "HAL/Errors.h"
 
+extern "C" {
 /**
  * Get the thread priority for the specified thread.
  *
@@ -94,10 +95,10 @@ HAL_Bool HAL_SetThreadPriority(NativeThreadHandle handle, HAL_Bool realTime,
     sch.sched_priority = 0;
   if (pthread_setschedparam(*handle, scheduler, &sch)) {
     *status = HAL_THREAD_PRIORITY_ERROR;
-    return true;
+    return false;
   } else {
     *status = 0;
-    return false;
+    return true;
   }
 }
 
@@ -118,3 +119,4 @@ HAL_Bool HAL_SetCurrentThreadPriority(HAL_Bool realTime, int32_t priority,
   auto thread = pthread_self();
   return HAL_SetThreadPriority(&thread, realTime, priority, status);
 }
+}