diff --git a/block/block-copy.c b/block/block-copy.c
index 93eb1b2664..eddb0b81e0 100644
--- a/block/block-copy.c
+++ b/block/block-copy.c
@@ -584,7 +584,7 @@ static coroutine_fn int block_copy_task_entry(AioTask *task)
     BlockCopyState *s = t->s;
     bool error_is_read = false;
     BlockCopyMethod method = t->method;
-    int ret;
+    int ret = -1;
 
     WITH_GRAPH_RDLOCK_GUARD() {
         ret = block_copy_do_copy(s, t->req.offset, t->req.bytes, &method,
diff --git a/block/file-posix.c b/block/file-posix.c
index ff928b5e85..90fa54352c 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -1398,7 +1398,7 @@ static void raw_refresh_zoned_limits(BlockDriverState *bs, struct stat *st,
                                      Error **errp)
 {
     BDRVRawState *s = bs->opaque;
-    BlockZoneModel zoned;
+    BlockZoneModel zoned = BLK_Z_NONE;
     int ret;
 
     ret = get_sysfs_zoned_model(st, &zoned);
diff --git a/block/mirror.c b/block/mirror.c
index 61f0a717b7..2afe700b4d 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -349,7 +349,7 @@ static void coroutine_fn mirror_co_read(void *opaque)
     MirrorOp *op = opaque;
     MirrorBlockJob *s = op->s;
     int nb_chunks;
-    uint64_t ret;
+    int ret = -1;
     uint64_t max_bytes;
 
     max_bytes = s->granularity * s->max_iov;
@@ -565,7 +565,7 @@ static void coroutine_fn GRAPH_UNLOCKED mirror_iteration(MirrorBlockJob *s)
 
     bitmap_set(s->in_flight_bitmap, offset / s->granularity, nb_chunks);
     while (nb_chunks > 0 && offset < s->bdev_length) {
-        int ret;
+        int ret = -1;
         int64_t io_bytes;
         int64_t io_bytes_acct;
         MirrorMethod mirror_method = MIRROR_METHOD_COPY;
@@ -841,7 +841,7 @@ static int coroutine_fn GRAPH_UNLOCKED mirror_dirty_init(MirrorBlockJob *s)
     int64_t offset;
     BlockDriverState *bs;
     BlockDriverState *target_bs = blk_bs(s->target);
-    int ret;
+    int ret = -1;
     int64_t count;
 
     bdrv_graph_co_rdlock();
@@ -931,7 +931,7 @@ static int coroutine_fn mirror_run(Job *job, Error **errp)
     MirrorBDSOpaque *mirror_top_opaque = s->mirror_top_bs->opaque;
     BlockDriverState *target_bs = blk_bs(s->target);
     bool need_drain = true;
-    BlockDeviceIoStatus iostatus;
+    BlockDeviceIoStatus iostatus = BLOCK_DEVICE_IO_STATUS__MAX;
     int64_t length;
     int64_t target_length;
     BlockDriverInfo bdi;
diff --git a/block/stream.c b/block/stream.c
index 7031eef12b..9076203193 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -155,8 +155,8 @@ static void stream_clean(Job *job)
 static int coroutine_fn stream_run(Job *job, Error **errp)
 {
     StreamBlockJob *s = container_of(job, StreamBlockJob, common.job);
-    BlockDriverState *unfiltered_bs;
-    int64_t len;
+    BlockDriverState *unfiltered_bs = NULL;
+    int64_t len = -1;
     int64_t offset = 0;
     int error = 0;
     int64_t n = 0; /* bytes */
@@ -177,7 +177,7 @@ static int coroutine_fn stream_run(Job *job, Error **errp)
 
     for ( ; offset < len; offset += n) {
         bool copy;
-        int ret;
+        int ret = -1;
 
         /* Note that even when no rate limit is applied we need to yield
          * with no pending I/O here so that bdrv_drain_all() returns.
diff --git a/fsdev/9p-iov-marshal.c b/fsdev/9p-iov-marshal.c
index a1c9beddd2..0c5a1a0fa2 100644
--- a/fsdev/9p-iov-marshal.c
+++ b/fsdev/9p-iov-marshal.c
@@ -84,9 +84,12 @@ ssize_t v9fs_iov_vunmarshal(struct iovec *out_sg, int out_num, size_t offset,
             break;
         }
         case 'w': {
-            uint16_t val, *valp;
+            uint16_t val = 0, *valp;
             valp = va_arg(ap, uint16_t *);
             copied = v9fs_unpack(&val, out_sg, out_num, offset, sizeof(val));
+            if (copied <= 0) {
+                break;
+            }
             if (bswap) {
                 *valp = le16_to_cpu(val);
             } else {
@@ -95,9 +98,12 @@ ssize_t v9fs_iov_vunmarshal(struct iovec *out_sg, int out_num, size_t offset,
             break;
         }
         case 'd': {
-            uint32_t val, *valp;
+            uint32_t val = 0, *valp;
             valp = va_arg(ap, uint32_t *);
             copied = v9fs_unpack(&val, out_sg, out_num, offset, sizeof(val));
+            if (copied <= 0) {
+                break;
+            }
             if (bswap) {
                 *valp = le32_to_cpu(val);
             } else {
@@ -106,9 +112,12 @@ ssize_t v9fs_iov_vunmarshal(struct iovec *out_sg, int out_num, size_t offset,
             break;
         }
         case 'q': {
-            uint64_t val, *valp;
+            uint64_t val = 0, *valp;
             valp = va_arg(ap, uint64_t *);
             copied = v9fs_unpack(&val, out_sg, out_num, offset, sizeof(val));
+            if (copied <= 0) {
+                break;
+            }
             if (bswap) {
                 *valp = le64_to_cpu(val);
             } else {
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index 115795392c..9166d7974d 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -1060,7 +1060,7 @@ static void virtio_blk_dma_restart_cb(void *opaque, bool running,
     VirtIOBlock *s = opaque;
     uint16_t num_queues = s->conf.num_queues;
     g_autofree VirtIOBlockReq **vq_rq = NULL;
-    VirtIOBlockReq *rq;
+    VirtIOBlockReq *rq = NULL;
 
     if (!running) {
         return;
diff --git a/hw/display/qxl.c b/hw/display/qxl.c
index 3c2b5182ca..0c4b1c9bf2 100644
--- a/hw/display/qxl.c
+++ b/hw/display/qxl.c
@@ -1301,8 +1301,8 @@ static int qxl_add_memslot(PCIQXLDevice *d, uint32_t slot_id, uint64_t delta,
     };
     uint64_t guest_start;
     uint64_t guest_end;
-    int pci_region;
-    pcibus_t pci_start;
+    int pci_region = -1;
+    pcibus_t pci_start = PCI_BAR_UNMAPPED;
     pcibus_t pci_end;
     MemoryRegion *mr;
     intptr_t virt_start;
diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c
index 7fc2a08df2..0eb24304ee 100644
--- a/hw/ide/ahci.c
+++ b/hw/ide/ahci.c
@@ -948,7 +948,6 @@ static int ahci_populate_sglist(AHCIDevice *ad, QEMUSGList *sglist,
     uint64_t sum = 0;
     int off_idx = -1;
     int64_t off_pos = -1;
-    int tbl_entry_size;
     IDEBus *bus = &ad->port;
     BusState *qbus = BUS(bus);
 
@@ -976,6 +975,8 @@ static int ahci_populate_sglist(AHCIDevice *ad, QEMUSGList *sglist,
     /* Get entries in the PRDT, init a qemu sglist accordingly */
     if (prdtl > 0) {
         AHCI_SG *tbl = (AHCI_SG *)prdt;
+        int tbl_entry_size = 0;
+
         sum = 0;
         for (i = 0; i < prdtl; i++) {
             tbl_entry_size = prdt_tbl_entry_size(&tbl[i]);
diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c
index 49cff2a0cb..22d16dc26b 100644
--- a/hw/scsi/vhost-scsi.c
+++ b/hw/scsi/vhost-scsi.c
@@ -172,7 +172,7 @@ static int vhost_scsi_set_workers(VHostSCSICommon *vsc, bool per_virtqueue)
     struct vhost_dev *dev = &vsc->dev;
     struct vhost_vring_worker vq_worker;
     struct vhost_worker_state worker;
-    int i, ret;
+    int i, ret = 0;
 
     /* Use default worker */
     if (!per_virtqueue || dev->nvqs == VHOST_SCSI_VQ_NUM_FIXED + 1) {
diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
index 87122e4245..ed01499391 100644
--- a/hw/sd/sdhci.c
+++ b/hw/sd/sdhci.c
@@ -747,7 +747,7 @@ static void sdhci_do_adma(SDHCIState *s)
     const uint16_t block_size = s->blksize & BLOCK_SIZE_MASK;
     const MemTxAttrs attrs = { .memory = true };
     ADMADescr dscr = {};
-    MemTxResult res;
+    MemTxResult res = MEMTX_ERROR;
     int i;
 
     if (s->trnmod & SDHC_TRNS_BLK_CNT_EN && !s->blkcnt) {
diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c
index fc5f408f77..37aca8b431 100644
--- a/hw/virtio/vhost-shadow-virtqueue.c
+++ b/hw/virtio/vhost-shadow-virtqueue.c
@@ -414,6 +414,7 @@ static uint16_t vhost_svq_last_desc_of_chain(const VhostShadowVirtqueue *svq,
     return i;
 }
 
+G_GNUC_WARN_UNUSED_RESULT
 static VirtQueueElement *vhost_svq_get_buf(VhostShadowVirtqueue *svq,
                                            uint32_t *len)
 {
@@ -526,10 +527,11 @@ static void vhost_svq_flush(VhostShadowVirtqueue *svq,
 size_t vhost_svq_poll(VhostShadowVirtqueue *svq, size_t num)
 {
     size_t len = 0;
-    uint32_t r;
 
     while (num--) {
+        g_autofree VirtQueueElement *elem = NULL;
         int64_t start_us = g_get_monotonic_time();
+        uint32_t r = 0;
 
         do {
             if (vhost_svq_more_used(svq)) {
@@ -541,7 +543,7 @@ size_t vhost_svq_poll(VhostShadowVirtqueue *svq, size_t num)
             }
         } while (true);
 
-        vhost_svq_get_buf(svq, &r);
+        elem = vhost_svq_get_buf(svq, &r);
         len += r;
     }
 
diff --git a/linux-user/hppa/cpu_loop.c b/linux-user/hppa/cpu_loop.c
index bc093b8fe8..23b38ff9b2 100644
--- a/linux-user/hppa/cpu_loop.c
+++ b/linux-user/hppa/cpu_loop.c
@@ -99,6 +99,8 @@ static abi_ulong hppa_lws(CPUHPPAState *env)
 #endif
             }
             break;
+        default:
+            g_assert_not_reached();
         }
         break;
     }
diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c
index 5478d58de3..233acb0855 100644
--- a/migration/dirtyrate.c
+++ b/migration/dirtyrate.c
@@ -149,12 +149,12 @@ int64_t vcpu_calculate_dirtyrate(int64_t calc_time_ms,
                                  unsigned int flag,
                                  bool one_shot)
 {
-    DirtyPageRecord *records;
+    DirtyPageRecord *records = NULL;
     int64_t init_time_ms;
     int64_t duration;
     int64_t dirtyrate;
     int i = 0;
-    unsigned int gen_id;
+    unsigned int gen_id = 0;
 
 retry:
     init_time_ms = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
diff --git a/migration/migration.c b/migration/migration.c
index ae2be31557..021faee2f3 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -2278,7 +2278,7 @@ static bool migrate_handle_rp_resume_ack(MigrationState *s,
  */
 static void migration_release_dst_files(MigrationState *ms)
 {
-    QEMUFile *file;
+    QEMUFile *file = NULL;
 
     WITH_QEMU_LOCK_GUARD(&ms->qemu_file_lock) {
         /*
diff --git a/migration/ram.c b/migration/ram.c
index 81eda2736a..326ce7eb79 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -1793,7 +1793,7 @@ static bool get_queued_page(RAMState *rs, PageSearchStatus *pss)
 {
     RAMBlock  *block;
     ram_addr_t offset;
-    bool dirty;
+    bool dirty = false;
 
     do {
         block = unqueue_page(rs, &offset);
diff --git a/nbd/client-connection.c b/nbd/client-connection.c
index f9da67c87e..b11e266807 100644
--- a/nbd/client-connection.c
+++ b/nbd/client-connection.c
@@ -410,7 +410,7 @@ nbd_co_establish_connection(NBDClientConnection *conn, NBDExportInfo *info,
  */
 void nbd_co_establish_connection_cancel(NBDClientConnection *conn)
 {
-    Coroutine *wait_co;
+    Coroutine *wait_co = NULL;
 
     WITH_QEMU_LOCK_GUARD(&conn->mutex) {
         wait_co = g_steal_pointer(&conn->wait_co);
diff --git a/qom/object.c b/qom/object.c
index 28c5b66eab..d3d3003541 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -2226,7 +2226,7 @@ Object *object_resolve_path_at(Object *parent, const char *path)
 
 Object *object_resolve_type_unambiguous(const char *typename, Error **errp)
 {
-    bool ambig;
+    bool ambig = false;
     Object *o = object_resolve_path_type("", typename, &ambig);
 
     if (ambig) {
diff --git a/target/loongarch/gdbstub.c b/target/loongarch/gdbstub.c
index 7ca245ee81..3a03cf9cba 100644
--- a/target/loongarch/gdbstub.c
+++ b/target/loongarch/gdbstub.c
@@ -34,26 +34,28 @@ void write_fcc(CPULoongArchState *env, uint64_t val)
 int loongarch_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n)
 {
     CPULoongArchState *env = cpu_env(cs);
-    uint64_t val;
-
-    if (0 <= n && n < 32) {
-        val = env->gpr[n];
-    } else if (n == 32) {
-        /* orig_a0 */
-        val = 0;
-    } else if (n == 33) {
-        val = env->pc;
-    } else if (n == 34) {
-        val = env->CSR_BADV;
-    }
 
     if (0 <= n && n <= 34) {
+        uint64_t val;
+
+        if (n < 32) {
+            val = env->gpr[n];
+        } else if (n == 32) {
+            /* orig_a0 */
+            val = 0;
+        } else if (n == 33) {
+            val = env->pc;
+        } else /* if (n == 34) */ {
+            val = env->CSR_BADV;
+        }
+
         if (is_la64(env)) {
             return gdb_get_reg64(mem_buf, val);
         } else {
             return gdb_get_reg32(mem_buf, val);
         }
     }
+
     return 0;
 }
 
diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c
index 666880472b..c112d5b189 100644
--- a/tests/unit/test-bdrv-drain.c
+++ b/tests/unit/test-bdrv-drain.c
@@ -722,7 +722,7 @@ static void test_blockjob_common_drain_node(enum drain_type drain_type,
     BlockJob *job;
     TestBlockJob *tjob;
     IOThread *iothread = NULL;
-    int ret;
+    int ret = -1;
 
     src = bdrv_new_open_driver(&bdrv_test, "source", BDRV_O_RDWR,
                                &error_abort);
diff --git a/tests/unit/test-block-iothread.c b/tests/unit/test-block-iothread.c
index 3766d5de6b..20ed54f570 100644
--- a/tests/unit/test-block-iothread.c
+++ b/tests/unit/test-block-iothread.c
@@ -745,7 +745,7 @@ static void test_propagate_mirror(void)
     AioContext *main_ctx = qemu_get_aio_context();
     BlockDriverState *src, *target, *filter;
     BlockBackend *blk;
-    Job *job;
+    Job *job = NULL;
     Error *local_err = NULL;
 
     /* Create src and target*/
diff --git a/util/qemu-coroutine.c b/util/qemu-coroutine.c
index eb4eebefdf..64d6264fc7 100644
--- a/util/qemu-coroutine.c
+++ b/util/qemu-coroutine.c
@@ -136,7 +136,7 @@ static Coroutine *coroutine_pool_get_local(void)
 static void coroutine_pool_refill_local(void)
 {
     CoroutinePool *local_pool = get_ptr_local_pool();
-    CoroutinePoolBatch *batch;
+    CoroutinePoolBatch *batch = NULL;
 
     WITH_QEMU_LOCK_GUARD(&global_pool_lock) {
         batch = QSLIST_FIRST(&global_pool);
diff --git a/util/qemu-timer.c b/util/qemu-timer.c
index 42b74c0444..ffe9a3c5c1 100644
--- a/util/qemu-timer.c
+++ b/util/qemu-timer.c
@@ -182,7 +182,7 @@ bool qemu_clock_has_timers(QEMUClockType type)
 
 bool timerlist_expired(QEMUTimerList *timer_list)
 {
-    int64_t expire_time;
+    int64_t expire_time = 0;
 
     if (!qatomic_read(&timer_list->active_timers)) {
         return false;
@@ -212,7 +212,7 @@ bool qemu_clock_expired(QEMUClockType type)
 int64_t timerlist_deadline_ns(QEMUTimerList *timer_list)
 {
     int64_t delta;
-    int64_t expire_time;
+    int64_t expire_time = 0;
 
     if (!qatomic_read(&timer_list->active_timers)) {
         return -1;
@@ -451,7 +451,7 @@ void timer_mod_ns(QEMUTimer *ts, int64_t expire_time)
 void timer_mod_anticipate_ns(QEMUTimer *ts, int64_t expire_time)
 {
     QEMUTimerList *timer_list = ts->timer_list;
-    bool rearm;
+    bool rearm = false;
 
     WITH_QEMU_LOCK_GUARD(&timer_list->active_timers_lock) {
         if (ts->expire_time == -1 || ts->expire_time > expire_time) {