Address review comments from @ChristosZosi

Author: paulbartell

portable/GCC/ARM_CR5/port.c

@@ -74,6 +74,15 @@
     #error configMAX_API_CALL_INTERRUPT_PRIORITY must be greater than ( configUNIQUE_INTERRUPT_PRIORITIES / 2 )
 #endif
 
+/*
+ * __ARM_FP is defined by the c preprocessor when FPU support is enabled,
+ * ususally with the -mfpu= argument and mfloat-abi=.
+ *
+ * Note: Some implementations of the c standard library may use FPU registers
+ *       for generic memory operations (memcpy, etc).
+ *       When setting configUSE_TASK_FPU_SUPPORT == 1, care must be taken to
+ *       ensure that the FPU registers are not used without an FPU context.
+ */
 #if configUSE_TASK_FPU_SUPPORT == 0
     #ifdef __ARM_FP
         #error __ARM_FP is defined, so configUSE_TASK_FPU_SUPPORT must be set to either to 1 or 2.

portable/GCC/ARM_CR5/portmacro.h

@@ -132,15 +132,16 @@ void FreeRTOS_Tick_Handler( void );
  */
 #if ( configUSE_TASK_FPU_SUPPORT == 1 )
     void vPortTaskUsesFPU( void );
+    #define portTASK_USES_FLOATING_POINT()    vPortTaskUsesFPU()
 #elif ( configUSE_TASK_FPU_SUPPORT == 2 )
 
 /*
  * Each task has an FPU context already, so define this function away to
  * prevent it being called accidentally.
  */
     #define vPortTaskUsesFPU()
+    #define portTASK_USES_FLOATING_POINT()
 #endif /* configUSE_TASK_FPU_SUPPORT */
-#define portTASK_USES_FLOATING_POINT()    vPortTaskUsesFPU()
 
 #define portLOWEST_INTERRUPT_PRIORITY           ( ( ( uint32_t ) configUNIQUE_INTERRUPT_PRIORITIES ) - 1UL )
 #define portLOWEST_USABLE_INTERRUPT_PRIORITY    ( portLOWEST_INTERRUPT_PRIORITY - 1UL )