Minor build warning fixes

libsel4platsupport/src/timer.c

diff --git a/libsel4platsupport/src/timer.c b/libsel4platsupport/src/timer.c
index e03a2b3..ead196d 100644
--- a/libsel4platsupport/src/timer.c
+++ b/libsel4platsupport/src/timer.c
@@ -177,7 +177,8 @@
     int error;
 
     /* initialise io ops */
-    ps_io_ops_t ops = {{ 0 }};
+    ps_io_ops_t ops;
+    memset(&ops, 0, sizeof(ops));
     error = sel4platsupport_new_io_ops(*vspace, *vka, &ops);
     if (!error) {
         /* we have no way of storing the fact that we allocated these io ops so we'll just leak
@@ -203,7 +204,8 @@
 int sel4platsupport_init_default_timer_caps(vka_t *vka, vspace_t *vspace, simple_t *simple, timer_objects_t *timer_objects)
 {
     /* initialise io ops */
-    ps_io_ops_t ops = {{ 0 }};
+    ps_io_ops_t ops;
+    memset(&ops, 0, sizeof(ops));
     int error = sel4platsupport_new_io_ops(*vspace, *vka, &ops);
     if (error) {
         ZF_LOGE("Failed to get io ops");

libsel4utils/src/elf.c

diff --git a/libsel4utils/src/elf.c b/libsel4utils/src/elf.c
index 76f4c3d..73cf9d6 100644
--- a/libsel4utils/src/elf.c
+++ b/libsel4utils/src/elf.c
@@ -372,7 +372,8 @@
 
             region->cacheable = 1;
             region->rights = rights_from_elf(elf_getProgramHeaderFlags(elf_file, i));
-            region->elf_vstart = (void*)elf_getProgramHeaderVaddr(elf_file, i);
+            // elf_getProgramHeaderMemorySize should just return `uintptr_t`
+            region->elf_vstart = (void*)(uintptr_t)elf_getProgramHeaderVaddr(elf_file, i);
             region->size = elf_getProgramHeaderMemorySize(elf_file, i);
             region->segment_index = i;
             region_id++;