Silence compiler warnings for expected and handled error conditions

Silly compiler emitting warnings that just cause people to break code
attempting to silence the compiler.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

4 files changed, 19 insertions, 5 deletions

diff --git a/lib/drmtest.c b/lib/drmtest.c
index 9a1232f4..632fec41 100644
--- a/lib/drmtest.c
+++ b/lib/drmtest.c
@@ -218,11 +218,11 @@ int drm_get_card(void)
 	return -1;
 }
 
-static void modprobe(const char *driver)
+static int modprobe(const char *driver)
 {
 	char buf[128];
 	snprintf(buf, sizeof(buf), "/sbin/modprobe -s %s", driver);
-	system(buf);
+	return system(buf);
 }
 
 /**
diff --git a/lib/igt_core.h b/lib/igt_core.h
index 59952331..64d823f6 100644
--- a/lib/igt_core.h
+++ b/lib/igt_core.h
@@ -297,6 +297,17 @@ void __igt_fail_assert(const char *domain, const char *file,
 void igt_exit(void) __attribute__((noreturn));
 
 /**
+ * igt_ignore_warn:
+ * @expr: condition to ignore
+ *
+ *
+ * Stops the compiler warning about an unused return value.
+ */
+static inline void igt_ignore_warn(bool value)
+{
+}
+
+/**
  * igt_assert:
  * @expr: condition to test
  *
diff --git a/tests/drv_missed_irq.c b/tests/drv_missed_irq.c
index 66d20edb..d0d9b391 100644
--- a/tests/drv_missed_irq.c
+++ b/tests/drv_missed_irq.c
@@ -129,8 +129,9 @@ igt_simple_main
 	fprintf(file, "0x%x", -1);
 	fclose(file);
 
+	expect_rings = -1;
 	file = igt_debugfs_fopen("i915_ring_test_irq", "r");
-	fscanf(file, "%x", &expect_rings);
+	igt_ignore_warn(fscanf(file, "%x", &expect_rings));
 	fclose(file);
 
 	igt_debug("Testing rings %x\n", expect_rings);
diff --git a/tests/kms_cursor_legacy.c b/tests/kms_cursor_legacy.c
index 00890c95..d98de526 100644
--- a/tests/kms_cursor_legacy.c
+++ b/tests/kms_cursor_legacy.c
@@ -245,7 +245,9 @@ static void flip(struct data *data,
 			drmModePageFlip(data->fd, crtc, fb_id,
 					DRM_MODE_PAGE_FLIP_EVENT,
 					NULL);
-			read(data->fd, buf, sizeof(buf));
+			while (read(data->fd, buf, sizeof(buf)) < 0 &&
+			       (errno == EINTR || errno == EAGAIN))
+				;
 			count++;
 		}
 
@@ -338,7 +340,7 @@ static void basic_flip(struct data *data)
 	igt_assert_eq(get_vblank(data->fd, 0, 0), vblank_start);
 
 	igt_set_timeout(1, "Stuck page flip");
-	read(data->fd, &buf, sizeof(buf));
+	igt_ignore_warn(read(data->fd, &buf, sizeof(buf)));
 	igt_assert_eq(get_vblank(data->fd, 0, 0), vblank_start + 1);
 	igt_reset_timeout();