altos/arm: Align data so that gcc 5.4 doesn't do byte-accesses. Add -Wcast-align

[fw/altos] / src / kernel / ao_task.h

diff --git a/src/kernel/ao_task.h b/src/kernel/ao_task.h
index f1dbd65426ae709353c0f226eda63a42c76ecaef..30b018ffe36aff064afb91b0a8fe1c41e1a20483 100644 (file)
--- a/src/kernel/ao_task.h
+++ b/src/kernel/ao_task.h
@@ -26,6 +26,17 @@
 #define HAS_TASK_INFO 1
 #endif
 
+/* arm stacks must be 32-bit aligned */
+#ifdef __arm__
+#define AO_STACK_ALIGNMENT __attribute__ ((aligned(4)))
+#endif
+#ifdef SDCC
+#define AO_STACK_ALIGNMENT
+#endif
+#ifdef __AVR__
+#define AO_STACK_ALIGNMENT
+#endif
+
 /* An AltOS task */
 struct ao_task {
        __xdata void *wchan;            /* current wait channel (NULL if running) */
@@ -37,7 +48,7 @@ struct ao_task {
        struct ao_list  queue;
        struct ao_list  alarm_queue;
 #endif
-       uint8_t stack[AO_STACK_SIZE];   /* saved stack */
+       uint8_t stack[AO_STACK_SIZE] AO_STACK_ALIGNMENT;        /* saved stack */
 #if HAS_SAMPLE_PROFILE
        uint32_t ticks;
        uint32_t yields;