From dc91fcdbc1dc8727ef17f1c8d13e818db2910ac5 Mon Sep 17 00:00:00 2001 From: Antonio Ospite Date: Thu, 29 Sep 2011 23:20:26 +0200 Subject: [PATCH] kinect_upload_fw: fix a -Wstrict-aliasing warning kinect_upload_fw.c:87:2: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] Use a union when there is the need to use the same memory for variables of incompatible types (especially if they have different storage size). --- kinect_upload_fw/kinect_upload_fw.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/kinect_upload_fw/kinect_upload_fw.c b/kinect_upload_fw/kinect_upload_fw.c index da909d5..51ef81e 100644 --- a/kinect_upload_fw/kinect_upload_fw.c +++ b/kinect_upload_fw/kinect_upload_fw.c @@ -83,31 +83,37 @@ static int get_first_reply(void) { } static int get_reply(void) { - unsigned char dump[512]; - status_code buffer = ((status_code*)dump)[0]; + union { + status_code buffer; + /* The following is needed because libusb_bulk_transfer might + * fail when working on a buffer smaller than 512 bytes. + */ + unsigned char dump[512]; + } reply; int res; int transferred; - res = libusb_bulk_transfer(dev, 0x81, (unsigned char*)&buffer, 512, &transferred, 0); + + res = libusb_bulk_transfer(dev, 0x81, reply.dump, 512, &transferred, 0); if(res != 0 || transferred != sizeof(status_code)) { LOG("Error reading reply: %d\ttransferred: %d (expected %lu)\n", res, transferred, sizeof(status_code)); return res; } - if(fn_le32(buffer.magic) != 0x0a6fe000) { - LOG("Error reading reply: invalid magic %08X\n",buffer.magic); + if(fn_le32(reply.buffer.magic) != 0x0a6fe000) { + LOG("Error reading reply: invalid magic %08X\n", reply.buffer.magic); return -1; } - if(fn_le32(buffer.seq) != seq) { - LOG("Error reading reply: non-matching sequence number %08X (expected %08X)\n", buffer.seq, seq); + if(fn_le32(reply.buffer.seq) != seq) { + LOG("Error reading reply: non-matching sequence number %08X (expected %08X)\n", reply.buffer.seq, seq); return -1; } - if(fn_le32(buffer.status) != 0) { - LOG("Notice reading reply: last uint32_t was nonzero: %d\n", buffer.status); + if(fn_le32(reply.buffer.status) != 0) { + LOG("Notice reading reply: last uint32_t was nonzero: %d\n", reply.buffer.status); } LOG("Reading reply: "); int i; for(i = 0; i < transferred; ++i) { - LOG("%02X ", ((unsigned char*)(&buffer))[i]); + LOG("%02X ", reply.dump[i]); } LOG("\n"); -- 2.1.4