Add definition of portDONT_DISCARD to ARMv7-M ports (#50)

Enabling Link Time Optimization (LTO) causes some of the functions used
in assembly to be incorrectly stripped off, resulting in linker error.
To avoid this, these functions are marked with portDONT_DISCARD macro,
definition of which is port specific. This commit adds the definition
of portDONT_DISCARD for ARMv7-M ports.

Signed-off-by: Gaurav Aggarwal

Author: aggarg

portable/GCC/ARM_CM0/portmacro.h

@@ -73,6 +73,7 @@ typedef unsigned long UBaseType_t;
 #define portSTACK_GROWTH			( -1 )
 #define portTICK_PERIOD_MS			( ( TickType_t ) 1000 / configTICK_RATE_HZ )
 #define portBYTE_ALIGNMENT			8
+#define portDONT_DISCARD			__attribute__(( used ))
 /*-----------------------------------------------------------*/
 
 

portable/GCC/ARM_CM3/portmacro.h

@@ -73,6 +73,7 @@ typedef unsigned long UBaseType_t;
 #define portSTACK_GROWTH			( -1 )
 #define portTICK_PERIOD_MS			( ( TickType_t ) 1000 / configTICK_RATE_HZ )
 #define portBYTE_ALIGNMENT			8
+#define portDONT_DISCARD			__attribute__(( used ))
 /*-----------------------------------------------------------*/
 
 /* Scheduler utilities. */

portable/GCC/ARM_CM3_MPU/portmacro.h

@@ -109,6 +109,7 @@ typedef struct MPU_SETTINGS
 #define portSTACK_GROWTH			( -1 )
 #define portTICK_PERIOD_MS			( ( TickType_t ) 1000 / configTICK_RATE_HZ )
 #define portBYTE_ALIGNMENT			8
+#define portDONT_DISCARD			__attribute__(( used ))
 /*-----------------------------------------------------------*/
 
 /* SVC numbers for various services. */

portable/GCC/ARM_CM4F/portmacro.h

@@ -73,6 +73,7 @@ typedef unsigned long UBaseType_t;
 #define portSTACK_GROWTH			( -1 )
 #define portTICK_PERIOD_MS			( ( TickType_t ) 1000 / configTICK_RATE_HZ )
 #define portBYTE_ALIGNMENT			8
+#define portDONT_DISCARD			__attribute__(( used ))
 /*-----------------------------------------------------------*/
 
 /* Scheduler utilities. */

portable/GCC/ARM_CM4_MPU/portmacro.h

@@ -109,6 +109,7 @@ typedef struct MPU_SETTINGS
 #define portSTACK_GROWTH			( -1 )
 #define portTICK_PERIOD_MS			( ( TickType_t ) 1000 / configTICK_RATE_HZ )
 #define portBYTE_ALIGNMENT			8
+#define portDONT_DISCARD			__attribute__(( used ))
 /*-----------------------------------------------------------*/
 
 /* SVC numbers for various services. */

portable/GCC/ARM_CM7/r0p1/portmacro.h

@@ -73,6 +73,7 @@ typedef unsigned long UBaseType_t;
 #define portSTACK_GROWTH			( -1 )
 #define portTICK_PERIOD_MS			( ( TickType_t ) 1000 / configTICK_RATE_HZ )
 #define portBYTE_ALIGNMENT			8
+#define portDONT_DISCARD			__attribute__(( used ))
 /*-----------------------------------------------------------*/
 
 /* Scheduler utilities. */