diff --git a/clients/presentation-shm.c b/clients/presentation-shm.c
index 828cb08d..2bb0aa1c 100644
--- a/clients/presentation-shm.c
+++ b/clients/presentation-shm.c
@@ -446,7 +446,7 @@ feedback_presented(void *data,
 	struct feedback *feedback = data;
 	struct window *window = feedback->window;
 	struct feedback *prev_feedback = window->received_feedback;
-	uint64_t seq = ((uint64_t)seq_hi << 32) + seq_lo;
+	uint64_t seq = u64_from_u32s(seq_hi, seq_lo);
 	const struct timespec *prevpresent;
 	uint32_t commit, present;
 	uint32_t f2c, c2p, f2p;
diff --git a/clients/simple-dmabuf-egl.c b/clients/simple-dmabuf-egl.c
index 16d47ba9..e63c320c 100644
--- a/clients/simple-dmabuf-egl.c
+++ b/clients/simple-dmabuf-egl.c
@@ -1010,7 +1010,7 @@ dmabuf_modifiers(void *data, struct zwp_linux_dmabuf_v1 *zwp_linux_dmabuf,
 		 uint32_t format, uint32_t modifier_hi, uint32_t modifier_lo)
 {
 	struct display *d = data;
-	uint64_t modifier = ((uint64_t)modifier_hi << 32) | modifier_lo;
+	uint64_t modifier = u64_from_u32s(modifier_hi, modifier_lo);
 
 	if (format != d->format) {
 		return;
diff --git a/clients/simple-dmabuf-v4l.c b/clients/simple-dmabuf-v4l.c
index a19570f9..50144986 100644
--- a/clients/simple-dmabuf-v4l.c
+++ b/clients/simple-dmabuf-v4l.c
@@ -730,7 +730,7 @@ dmabuf_modifier(void *data, struct zwp_linux_dmabuf_v1 *zwp_linux_dmabuf,
 		 uint32_t format, uint32_t modifier_hi, uint32_t modifier_lo)
 {
 	struct display *d = data;
-	uint64_t modifier = ((uint64_t) modifier_hi << 32 ) | modifier_lo;
+	uint64_t modifier = u64_from_u32s(modifier_hi, modifier_lo);
 
 	if (format == d->drm_format && modifier == DRM_FORMAT_MOD_LINEAR)
 		d->requested_format_found = true;
diff --git a/clients/window.c b/clients/window.c
index 3036bb42..0d9d6cec 100644
--- a/clients/window.c
+++ b/clients/window.c
@@ -4704,7 +4704,7 @@ relative_pointer_handle_motion(void *data, struct zwp_relative_pointer_v1 *point
 {
 	struct input *input = data;
 	struct window *window = input->pointer_focus;
-	uint32_t ms = (((uint64_t) utime_hi) << 32 | utime_lo) / 1000;
+	uint32_t ms = u64_from_u32s(utime_hi, utime_lo) / 1000;
 
 	if (window->locked_pointer_motion_handler &&
 	    window->pointer_locked) {
diff --git a/libweston/backend-drm/kms.c b/libweston/backend-drm/kms.c
index 0118efa1..6c6e7e59 100644
--- a/libweston/backend-drm/kms.c
+++ b/libweston/backend-drm/kms.c
@@ -1382,12 +1382,12 @@ drm_pending_state_apply_sync(struct drm_pending_state *pending_state)
 void
 drm_output_update_msc(struct drm_output *output, unsigned int seq)
 {
-	uint64_t msc_hi = output->base.msc >> 32;
+	uint32_t msc_hi = output->base.msc >> 32;
 
 	if (seq < (output->base.msc & 0xffffffff))
 		msc_hi++;
 
-	output->base.msc = (msc_hi << 32) + seq;
+	output->base.msc = u64_from_u32s(msc_hi, seq);
 }
 
 static void
diff --git a/libweston/linux-dmabuf.c b/libweston/linux-dmabuf.c
index b73508e3..1a9e31d5 100644
--- a/libweston/linux-dmabuf.c
+++ b/libweston/linux-dmabuf.c
@@ -37,6 +37,7 @@
 #include "linux-dmabuf.h"
 #include "linux-dmabuf-unstable-v1-server-protocol.h"
 #include "shared/os-compatibility.h"
+#include "shared/helpers.h"
 #include "libweston-internal.h"
 #include "shared/weston-drm-fourcc.h"
 
@@ -121,8 +122,7 @@ params_add(struct wl_client *client,
 	if (wl_resource_get_version(params_resource) < ZWP_LINUX_DMABUF_V1_MODIFIER_SINCE_VERSION)
 		buffer->attributes.modifier[plane_idx] = DRM_FORMAT_MOD_INVALID;
 	else
-		buffer->attributes.modifier[plane_idx] = ((uint64_t)modifier_hi << 32) |
-							 modifier_lo;
+		buffer->attributes.modifier[plane_idx] = u64_from_u32s(modifier_hi, modifier_lo);
 
 	buffer->attributes.n_planes++;
 }
diff --git a/shared/helpers.h b/shared/helpers.h
index 7b722096..32938eca 100644
--- a/shared/helpers.h
+++ b/shared/helpers.h
@@ -22,6 +22,8 @@
 #ifndef WESTON_HELPERS_H
 #define WESTON_HELPERS_H
 
+#include <stdint.h>
+
 #ifdef  __cplusplus
 extern "C" {
 #endif
@@ -171,6 +173,12 @@ do { \
  */
 #define WESTON_EXPORT_FOR_TESTS __attribute__ ((visibility("default")))
 
+static inline uint64_t
+u64_from_u32s(uint32_t hi, uint32_t lo)
+{
+	return ((uint64_t)hi << 32) + lo;
+}
+
 #ifdef  __cplusplus
 }
 #endif
diff --git a/shared/timespec-util.h b/shared/timespec-util.h
index f79969bb..f76b9537 100644
--- a/shared/timespec-util.h
+++ b/shared/timespec-util.h
@@ -30,6 +30,7 @@
 #include <assert.h>
 #include <time.h>
 #include <stdbool.h>
+#include <shared/helpers.h>
 
 #define NSEC_PER_SEC 1000000000
 
@@ -216,7 +217,7 @@ static inline void
 timespec_from_proto(struct timespec *a, uint32_t tv_sec_hi,
                     uint32_t tv_sec_lo, uint32_t tv_nsec)
 {
-	a->tv_sec = ((uint64_t)tv_sec_hi << 32) + tv_sec_lo;
+	a->tv_sec = u64_from_u32s(tv_sec_hi, tv_sec_lo);
 	a->tv_nsec = tv_nsec;
 }
 
diff --git a/tests/presentation-test.c b/tests/presentation-test.c
index f6e3a7bc..6e2112bd 100644
--- a/tests/presentation-test.c
+++ b/tests/presentation-test.c
@@ -123,7 +123,7 @@ feedback_presented(void *data,
 
 	assert(fb->result == FB_PENDING);
 	fb->result = FB_PRESENTED;
-	fb->seq = ((uint64_t)seq_hi << 32) + seq_lo;
+	fb->seq = u64_from_u32s(seq_hi, seq_lo);
 	timespec_from_proto(&fb->time, tv_sec_hi, tv_sec_lo, tv_nsec);
 	fb->refresh_nsec = refresh_nsec;
 	fb->flags = flags;