diff --git a/lib/igt.cocci b/lib/igt.cocci
index 7dc398d..156f0cf 100644
--- a/lib/igt.cocci
+++ b/lib/igt.cocci
@@ -173,3 +173,31 @@ int E3, E4;
 - igt_assert(E3 < E4);
 + igt_assert_lt(E3, E4);
 )
+
+// avoid unused-result warnings when compiling with _FORTIFY_SOURCE defined
+@@
+identifier func =~ "^(read|write)$";
+expression list[2] E;
+expression size;
+@@
+-func(E, size);
++igt_assert_eq(func(E, size), size);
+
+@@
+expression ptr, size, nmemb, stream;
+@@
+-fread(ptr, size, nmemb, stream);
++igt_assert_eq(fread(ptr, size, nmemb, stream), nmemb);
+
+@@
+expression list E;
+@@
+-fgets(E);
++igt_assert_neq(fgets(E), NULL);
+
+@@
+identifier func =~ "^v?asprintf$";
+expression list E;
+@@
+-func(E);
++igt_assert_neq(func(E), -1);
diff --git a/lib/igt_core.c b/lib/igt_core.c
index 7445eab..3a6dc79 100644
--- a/lib/igt_core.c
+++ b/lib/igt_core.c
@@ -412,13 +412,15 @@ static void low_mem_killer_disable(bool disable)
 		/* writing 9999 to this module parameter effectively diables the
 		 * low memory killer. This is not a real file, so we dont need to
 		 * seek to the start or truncate it */
-		write(fd, no_lowmem_killer, sizeof(no_lowmem_killer));
+		igt_assert_eq(write(fd, no_lowmem_killer, sizeof(no_lowmem_killer)),
+			      sizeof(no_lowmem_killer));
 		close(fd);
 	} else {
 		/* just re-enstate the original settings */
 		fd = open(adj_fname, O_WRONLY);
 		igt_assert(fd != -1);
-		write(fd, prev_adj_scores, adj_scores_len);
+		igt_assert_eq(write(fd, prev_adj_scores, adj_scores_len),
+			      adj_scores_len);
 		close(fd);
 	}
 
@@ -859,7 +861,8 @@ void __igt_skip_check(const char *file, const int line,
 	char *err_str = NULL;
 
 	if (err)
-		asprintf(&err_str, "Last errno: %i, %s\n", err, strerror(err));
+		igt_assert_neq(asprintf(&err_str, "Last errno: %i, %s\n", err, strerror(err)),
+			       -1);
 
 	if (f) {
 		static char *buf;
@@ -869,7 +872,7 @@ void __igt_skip_check(const char *file, const int line,
 			free(buf);
 
 		va_start(args, f);
-		vasprintf(&buf, f, args);
+		igt_assert_neq(vasprintf(&buf, f, args), -1);
 		va_end(args);
 
 		igt_skip("Test requirement not met in function %s, file %s:%i:\n"
@@ -1396,10 +1399,11 @@ static void fatal_sig_handler(int sig)
 
 	for (i = 0; i < ARRAY_SIZE(handled_signals); i++) {
 		if (handled_signals[i].number == sig) {
-			write(STDERR_FILENO, "Received signal ", 16);
-			write(STDERR_FILENO, handled_signals[i].name,
-			      handled_signals[i].name_len);
-			write(STDERR_FILENO, ".\n", 2);
+			igt_assert_eq(write(STDERR_FILENO, "Received signal ", 16),
+                                      16);
+			igt_assert_eq(write(STDERR_FILENO, handled_signals[i].name, handled_signals[i].name_len),
+                                      handled_signals[i].name_len);
+			igt_assert_eq(write(STDERR_FILENO, ".\n", 2), 2);
 			break;
 		}
 	}
diff --git a/lib/igt_debugfs.c b/lib/igt_debugfs.c
index 85c3f22..df7f453 100644
--- a/lib/igt_debugfs.c
+++ b/lib/igt_debugfs.c
@@ -273,7 +273,7 @@ static bool igt_pipe_crc_do_start(igt_pipe_crc_t *pipe_crc)
 	sprintf(buf, "pipe %s %s", kmstest_pipe_name(pipe_crc->pipe),
 		pipe_crc_source_name(pipe_crc->source));
 	errno = 0;
-	write(pipe_crc->ctl_fd, buf, strlen(buf));
+	igt_assert_eq(write(pipe_crc->ctl_fd, buf, strlen(buf)), strlen(buf));
 	if (errno != 0)
 		return false;
 
@@ -285,7 +285,7 @@ static void igt_pipe_crc_pipe_off(int fd, enum pipe pipe)
 	char buf[32];
 
 	sprintf(buf, "pipe %s none", kmstest_pipe_name(pipe));
-	write(fd, buf, strlen(buf));
+	igt_assert_eq(write(fd, buf, strlen(buf)), strlen(buf));
 }
 
 static void igt_pipe_crc_reset(void)
@@ -417,7 +417,7 @@ void igt_pipe_crc_stop(igt_pipe_crc_t *pipe_crc)
 	char buf[32];
 
 	sprintf(buf, "pipe %s none", kmstest_pipe_name(pipe_crc->pipe));
-	write(pipe_crc->ctl_fd, buf, strlen(buf));
+	igt_assert_eq(write(pipe_crc->ctl_fd, buf, strlen(buf)), strlen(buf));
 }
 
 static bool pipe_crc_init_from_string(igt_crc_t *crc, const char *line)
diff --git a/lib/igt_kms.c b/lib/igt_kms.c
index 9c131f0..6cb1f08 100644
--- a/lib/igt_kms.c
+++ b/lib/igt_kms.c
@@ -434,9 +434,8 @@ bool kmstest_force_connector(int drm_fd, drmModeConnector *connector,
 		break;
 	}
 
-	asprintf(&path, "%s-%d/force",
-		 kmstest_connector_type_str(connector->connector_type),
-		 connector->connector_type_id);
+	igt_assert_neq(asprintf(&path, "%s-%d/force", kmstest_connector_type_str(connector->connector_type), connector->connector_type_id),
+		       -1);
 	debugfs_fd = igt_debugfs_open(path, O_WRONLY | O_TRUNC);
 
 	if (debugfs_fd == -1) {
@@ -494,9 +493,8 @@ void kmstest_force_edid(int drm_fd, drmModeConnector *connector,
 	char *path;
 	int debugfs_fd, ret;
 
-	asprintf(&path, "%s-%d/edid_override",
-		 kmstest_connector_type_str(connector->connector_type),
-		 connector->connector_type_id);
+	igt_assert_neq(asprintf(&path, "%s-%d/edid_override", kmstest_connector_type_str(connector->connector_type), connector->connector_type_id),
+		       -1);
 	debugfs_fd = igt_debugfs_open(path, O_WRONLY | O_TRUNC);
 	free(path);
 
@@ -910,9 +908,8 @@ static void igt_output_refresh(igt_output_t *output)
 	if (!output->name) {
 		drmModeConnector *c = output->config.connector;
 
-		asprintf(&output->name, "%s-%d",
-			 kmstest_connector_type_str(c->connector_type),
-			 c->connector_type_id);
+		igt_assert_neq(asprintf(&output->name, "%s-%d", kmstest_connector_type_str(c->connector_type), c->connector_type_id),
+			       -1);
 	}
 
 	LOG(display, "%s: Selecting pipe %s\n", output->name,
diff --git a/lib/intel_os.c b/lib/intel_os.c
index 1badd3e..3321a8d 100644
--- a/lib/intel_os.c
+++ b/lib/intel_os.c
@@ -255,7 +255,7 @@ intel_purge_vm_caches(void)
 	if (fd < 0)
 		return;
 
-	write(fd, "3\n", 2);
+	igt_assert_eq(write(fd, "3\n", 2), 2);
 	close(fd);
 }
 
diff --git a/lib/rendercopy_gen8.c b/lib/rendercopy_gen8.c
index baed762..a7fc2c4 100644
--- a/lib/rendercopy_gen8.c
+++ b/lib/rendercopy_gen8.c
@@ -30,7 +30,7 @@
 static void dump_batch(struct intel_batchbuffer *batch) {
 	int fd = open("/tmp/i965-batchbuffers.dump", O_WRONLY | O_CREAT,  0666);
 	if (fd != -1) {
-		write(fd, batch->buffer, 4096);
+		igt_assert_eq(write(fd, batch->buffer, 4096), 4096);
 		fd = close(fd);
 	}
 }
diff --git a/lib/rendercopy_gen9.c b/lib/rendercopy_gen9.c
index b7b133c..0766192 100644
--- a/lib/rendercopy_gen9.c
+++ b/lib/rendercopy_gen9.c
@@ -31,7 +31,7 @@
 static void dump_batch(struct intel_batchbuffer *batch) {
 	int fd = open("/tmp/i965-batchbuffers.dump", O_WRONLY | O_CREAT,  0666);
 	if (fd != -1) {
-		write(fd, batch->buffer, 4096);
+		igt_assert_eq(write(fd, batch->buffer, 4096), 4096);
 		fd = close(fd);
 	}
 }
diff --git a/tests/kms_fbc_crc.c b/tests/kms_fbc_crc.c
index 4256fed..10e1ca4 100644
--- a/tests/kms_fbc_crc.c
+++ b/tests/kms_fbc_crc.c
@@ -198,7 +198,7 @@ static bool fbc_enabled(data_t *data)
 	status = igt_debugfs_fopen("i915_fbc_status", "r");
 	igt_assert(status);
 
-	fread(str, sizeof(str) - 1, 1, status);
+	igt_assert_eq(fread(str, sizeof(str) - 1, 1, status), 1);
 	fclose(status);
 	return strstr(str, "FBC enabled") != NULL;
 }
@@ -510,7 +510,7 @@ igt_main
 
 		status = igt_debugfs_fopen("i915_fbc_status", "r");
 		igt_require_f(status, "No i915_fbc_status found\n");
-		fread(buf, sizeof(buf), 1, status);
+		igt_assert_eq(fread(buf, sizeof(buf), 1, status), sizeof(buf));
 		fclose(status);
 		buf[sizeof(buf) - 1] = '\0';
 		igt_require_f(!strstr(buf, "unsupported by this chipset") &&
diff --git a/tests/kms_vblank.c b/tests/kms_vblank.c
index 569390e..5a00ccc 100644
--- a/tests/kms_vblank.c
+++ b/tests/kms_vblank.c
@@ -101,7 +101,7 @@ static void query(int fd, bool busy)
 		 busy ? "busy" : "idle", elapsed(&start, &end, count));
 
 	if (busy)
-		read(fd, buf, sizeof(buf));
+		igt_assert_eq(read(fd, buf, sizeof(buf)), sizeof(buf));
 }
 
 igt_main
diff --git a/tests/pm_lpsp.c b/tests/pm_lpsp.c
index 50b3dd9..3ed4c78 100644
--- a/tests/pm_lpsp.c
+++ b/tests/pm_lpsp.c
@@ -45,12 +45,12 @@ static void disable_audio_runtime_pm(void)
 
 	fd = open("/sys/module/snd_hda_intel/parameters/power_save", O_WRONLY);
 	if (fd >= 0) {
-		write(fd, "1\n", 2);
+		igt_assert_eq(write(fd, "1\n", 2), 2);
 		close(fd);
 	}
 	fd = open("/sys/bus/pci/devices/0000:00:03.0/power/control", O_WRONLY);
 	if (fd >= 0) {
-		write(fd, "auto\n", 5);
+		igt_assert_eq(write(fd, "auto\n", 5), 5);
 		close(fd);
 	}
 	/* Give some time for it to react. */
diff --git a/tests/prime_udl.c b/tests/prime_udl.c
index 62b381a..d03aee0 100644
--- a/tests/prime_udl.c
+++ b/tests/prime_udl.c
@@ -61,7 +61,7 @@ static int find_and_open_devices(void)
 		if (!fl)
 			break;
 
-		fgets(vendor_id, 8, fl);
+		igt_assert_neq(fgets(vendor_id, 8, fl), NULL);
 		fclose(fl);
 
 		venid = strtoul(vendor_id, NULL, 16);
