Am 15.08.2012 16:16, schrieb Stefan Hajnoczi:
On Fri, Aug 10, 2012 at 10:03:27PM +0200, Stefan Weil wrote:
QEMU_PACKED results in a MinGW compiler warning when it is
used for single structure elements:
warning: 'gcc_struct' attribute ignored
Using QEMU_PACKED for the whole structure avoids the compiler warning
without changing the memory layout.
Quick link for other reviewers:
http://gcc.gnu.org/onlinedocs/gcc-4.7.1/gcc/Type-Attributes.html#Type-Attributes
Signed-off-by: Stefan Weil <s...@weilnetz.de>
---
hw/srp.h | 8 ++++----
1 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/hw/srp.h b/hw/srp.h
index 3009bd5..5e0cad5 100644
--- a/hw/srp.h
+++ b/hw/srp.h
@@ -177,13 +177,13 @@ struct srp_tsk_mgmt {
uint8_t reserved1[6];
uint64_t tag;
uint8_t reserved2[4];
- uint64_t lun QEMU_PACKED;
+ uint64_t lun;
uint8_t reserved3[2];
uint8_t tsk_mgmt_func;
uint8_t reserved4;
uint64_t task_tag;
uint8_t reserved5[8];
-};
+} QEMU_PACKED;
Here I actually see a difference for the uint64_t task_tag field.
Previously it was not packed, now it is packed and because it has 4 *
uint8_t before it there will be a difference in layout.
Looking at how QEMU accesses srp_tsk_mgmt, I think we're safe because we
never actually access task_tag?
Ben: Any thoughts on this patch?
Stefan
4 * uint8_t + 4 bytes from the packed lun, so there is no change
for task_tag, it's always on a 8 byte boundary!
Regards,
Stefan
