fix remaining compiler warnings

This commit removes all inline annotations that
the compiler does not actually inline, and inserts
pragma directives to selectively disable warnings
where necessary.

arch/at91sam3x8e/handle_fault.c

@@ -17,7 +17,7 @@ static void uart_write_sync(const char *s)
 }
 
 /** Setup UART to manual byte-by-byte control */
-static inline void uart_emergency_setup(void)
+static void uart_emergency_setup(void)
 {
 	UART->UART_IDR = 0xffffffff;
 
@@ -34,7 +34,7 @@ static inline void uart_emergency_setup(void)
 
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wswitch"
-static inline void print_err_msg(enum irqno irqno)
+static void print_err_msg(enum irqno irqno)
 {
 	uart_write_sync("\n\n########## SERIOUS BRUH MOMENT! ##########\n");
 
@@ -100,9 +100,9 @@ static void print_regs(struct exc_context *context)
 	print_reg("R10", context->r10);
 	print_reg("R11", context->r11);
 	print_reg("R12", context->sp->r12);
-	print_reg("SP", *(word_t *)&context->sp);
+	print_reg("SP", (word_t)context->sp);
-	print_reg("LR", *(word_t *)&context->sp->lr);
+	print_reg("LR", (word_t)context->sp->lr);
-	print_reg("PC", *(word_t *)&context->sp->pc);
+	print_reg("PC", (word_t)context->sp->pc);
 	print_reg("xPSR", context->sp->psr);
 }
 

kernel/kevent.c

@@ -48,7 +48,7 @@ void kevents_init(void)
 }
 
 /* called from scheduler context only */
-static inline void process_single_queue(struct kevent_queue *queue, struct list_head *listeners)
+static void process_single_queue(struct kevent_queue *queue, struct list_head *listeners)
 {
 	struct kevent *event, *tmp_event;
 

kernel/mm.c

@@ -167,7 +167,7 @@ static struct memblk *blk_slice(struct list_head *heap, struct memblk *bottom, s
 long sys_malloc(size_t size)
 {
 	void *ptr = kmalloc(size);
-	return *(long *)&ptr;
+	return (long)ptr;
 }
 
 void sys_free(void *ptr)
@@ -348,8 +348,8 @@ static struct memblk *blk_try_merge(struct list_head *heap, struct memblk *blk)
 }
 
 static struct memblk *blk_merge(struct list_head *heap,
-				       struct memblk *bottom,
+				struct memblk *bottom,
-				       struct memblk *top)
+				struct memblk *top)
 {
 	size_t bottom_size = blk_get_size(bottom);
 	size_t top_size = blk_get_size(top);
@@ -368,7 +368,8 @@ static struct memblk *blk_merge(struct list_head *heap,
 	return bottom;
 }
 
-static struct memblk *blk_slice(struct list_head *heap, struct memblk *blk, size_t slice_size)
+static struct memblk *blk_slice(struct list_head *heap, struct memblk *blk,
+				size_t slice_size)
 {
 	list_delete(&blk->list);
 
@@ -412,7 +413,7 @@ static struct memblk *blk_slice(struct list_head *heap, struct memblk *blk, size
 	return blk;
 }
 
-static inline size_t round_alloc_size_up(size_t size)
+static size_t round_alloc_size_up(size_t size)
 {
 	size_t rounded = (size / MIN_SIZE) * MIN_SIZE;
 	if (rounded < size)
@@ -436,7 +437,7 @@ static void blk_set_size(struct memblk *blk, size_t size)
 	blk->endsz[words] |= size;
 }
 
-static inline void blk_set_alloc(struct memblk *blk)
+static void blk_set_alloc(struct memblk *blk)
 {
 	size_t words = blk->size / sizeof(blk->size);
 
@@ -444,7 +445,7 @@ static inline void blk_set_alloc(struct memblk *blk)
 	blk->endsz[words] |= ALLOC_FLAG;
 }
 
-static inline void blk_clear_alloc(struct memblk *blk)
+static void blk_clear_alloc(struct memblk *blk)
 {
 	size_t words = blk->size / sizeof(blk->size);
 
@@ -472,32 +473,38 @@ static inline int blk_is_border_start(struct memblk *blk)
 	return blk->size & BORDER_FLAG;
 }
 
-static inline void blk_set_border_end(struct memblk *blk)
+static void blk_set_border_end(struct memblk *blk)
 {
 	size_t words = blk->size / sizeof(blk->size);
 	blk->endsz[words] |= BORDER_FLAG;
 }
 
-static inline void blk_clear_border_end(struct memblk *blk)
+static void blk_clear_border_end(struct memblk *blk)
 {
 	size_t words = blk->size / sizeof(blk->size);
 	blk->endsz[words] &= ~BORDER_FLAG;
 }
 
-static inline int blk_is_border_end(struct memblk *blk)
+static int blk_is_border_end(struct memblk *blk)
 {
 	size_t words = blk->size / sizeof(blk->size);
 	return blk->endsz[words] & BORDER_FLAG;
 }
 
-static inline struct memblk *blk_prev(struct memblk *blk)
+static struct memblk *blk_prev(struct memblk *blk)
 {
 	if (blk_is_border_start(blk))
 		return NULL;
+
+	/* gcc does not like accessing index -1 of zero-length arrays */
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Warray-bounds"
+#pragma GCC diagnostic ignored "-Wzero-length-bounds"
 	return (void *)blk - (blk->prevsz[-1] & SIZE_MSK) - OVERHEAD;
+#pragma GCC diagnostic pop
 }
 
-static inline struct memblk *blk_next(struct memblk *blk)
+static struct memblk *blk_next(struct memblk *blk)
 {
 	if (blk_is_border_end(blk))
 		return NULL;

kernel/sched.c

@@ -79,7 +79,11 @@ int sched_init(void)
 
 	memset(&kernel_task.tcb, 0, sizeof(kernel_task.tcb));
 	kernel_task.bottom = &_estack;
+	/* gcc thinks &_estack is an array of size 1 */
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Warray-bounds"
 	kernel_task.stack = kernel_task.bottom - CONFIG_STACK_SIZE;
+#pragma GCC diagnostic pop
 	kernel_task.pid = 0;
 	kernel_task.state = TASK_RUNNING;
 
@@ -121,10 +125,14 @@ out:
 /**
  * @brief Determine whether the specified task is a candidate for execution.
  *
+ * This function is only called once from `schedule()` and performance critical,
+ * hence the `__always_inline` attribute.
+ *
  * @param task The task
  * @returns whether `task` could be run next
  */
-static inline bool can_run(const struct task *task)
+__always_inline
+static bool can_run(const struct task *task)
 {
 	switch (task->state) {
 	case TASK_SLEEP:

lib/printf.c

@@ -135,7 +135,7 @@ static int fmt_handle_uint(struct printf_buf *buf, unsigned int u)
 	return ret;
 }
 
-static inline int fmt_handle_int(struct printf_buf *buf, int i)
+static int fmt_handle_int(struct printf_buf *buf, int i)
 {
 	int ret = 0;
 	char minus = '-';
@@ -160,7 +160,7 @@ static inline int fmt_handle_int(struct printf_buf *buf, int i)
  * @param args: A pointer to the varargs list.  Will be manipulated.
  * @returns The amount of bytes written, or a negative POSIX error code.
  */
-static inline int fmt_handle(struct printf_buf *buf, const char **pos, va_list args)
+static int fmt_handle(struct printf_buf *buf, const char **pos, va_list args)
 {
 	int ret = 0;
 	union {

lib/stdlib.c

@@ -19,7 +19,7 @@ void *malloc(size_t size)
 		return NULL;
 	} else {
 		long int intptr = syscall(SYS_malloc, (sysarg_t)size);
-		return *(void **)&intptr;
+		return (void *)intptr;
 	}
 }
 
@@ -29,7 +29,7 @@ void *calloc(size_t nmemb, size_t size)
 	if (nmemb != 0 && total / nmemb != size)
 		return NULL; /* overflow check as mandated by POSIX.1 */
 	long int intptr = syscall(SYS_malloc, (sysarg_t)total);
-	return *(void **)&intptr;
+	return (void *)intptr;
 }
 
 void free(void *ptr)