diff --git a/src/uml/uml_conf.c b/src/uml/uml_conf.c
index e9d3ddb3ec..18cff50569 100644
--- a/src/uml/uml_conf.c
+++ b/src/uml/uml_conf.c
@@ -384,7 +384,7 @@ virCommandPtr umlBuildCommandLine(virConnectPtr conn,
                                   struct uml_driver *driver,
                                   virDomainObjPtr vm)
 {
-    int i, j;
+    size_t i, j;
     virCommandPtr cmd;
 
     cmd = virCommandNew(vm->def->os.kernel);
@@ -428,7 +428,7 @@ virCommandPtr umlBuildCommandLine(virConnectPtr conn,
         if (chr)
             ret = umlBuildCommandLineChr(chr, "con", cmd);
         if (!ret)
-            if (virAsprintf(&ret, "con%d=none", i) < 0)
+            if (virAsprintf(&ret, "con%zu=none", i) < 0)
                 goto error;
         virCommandAddArg(cmd, ret);
         VIR_FREE(ret);
@@ -443,7 +443,7 @@ virCommandPtr umlBuildCommandLine(virConnectPtr conn,
         if (chr)
             ret = umlBuildCommandLineChr(chr, "ssl", cmd);
         if (!ret)
-            if (virAsprintf(&ret, "ssl%d=none", i) < 0)
+            if (virAsprintf(&ret, "ssl%zu=none", i) < 0)
                 goto error;
 
         virCommandAddArg(cmd, ret);
diff --git a/src/uml/uml_driver.c b/src/uml/uml_driver.c
index eea68db102..7abcd6bb00 100644
--- a/src/uml/uml_driver.c
+++ b/src/uml/uml_driver.c
@@ -273,7 +273,7 @@ static int
 umlIdentifyChrPTY(struct uml_driver *driver,
                   virDomainObjPtr dom)
 {
-    int i;
+    size_t i;
 
     for (i = 0; i < dom->def->nconsoles; i++)
         if (dom->def->consoles[i]->source.type == VIR_DOMAIN_CHR_TYPE_PTY)
@@ -995,7 +995,7 @@ error:
 
 
 static void umlCleanupTapDevices(virDomainObjPtr vm) {
-    int i;
+    size_t i;
 
     for (i = 0; i < vm->def->nnets; i++) {
         virDomainNetDefPtr def = vm->def->nets[i];
@@ -2115,7 +2115,7 @@ static int umlDomainAttachUmlDisk(struct uml_driver *driver,
                                   virDomainObjPtr vm,
                                   virDomainDiskDefPtr disk)
 {
-    int i;
+    size_t i;
     char *cmd = NULL;
     char *reply = NULL;
 
@@ -2239,7 +2239,8 @@ static int umlDomainDetachUmlDisk(struct uml_driver *driver,
                                   virDomainObjPtr vm,
                                   virDomainDeviceDefPtr dev)
 {
-    int i, ret = -1;
+    size_t i;
+    int ret = -1;
     virDomainDiskDefPtr detach = NULL;
     char *cmd;
     char *reply;