Allow building on musl

---

--- a/benchmarks/gem_syslatency.c
+++ b/benchmarks/gem_syslatency.c
@@ -44,7 +44,11 @@

 #include <linux/unistd.h>

-#define sigev_notify_thread_id _sigev_un._tid
+#ifndef __GLIBC__
+#include "signal_compat.h"
+#endif
+
+#define sigev_notify_thread_id sigev_notify_function

 static volatile int done;

--- a/lib/igt_aux.c
+++ b/lib/igt_aux.c
@@ -31,6 +31,7 @@
 #endif
 #include <stdio.h>
 #include <fcntl.h>
+#include <limits.h> // PATH_MAX
 #include <sys/stat.h>
 #include <sys/ioctl.h>
 #include <string.h>
@@ -73,6 +74,12 @@
 #include <libgen.h>   /* for dirname() */
 #endif

+#ifndef __GLIBC__
+#include "signal_compat.h"
+#endif
+
+//#include <asm-generic/siginfo.h>
+
 /**
  * SECTION:igt_aux
  * @short_description: Auxiliary libraries and support functions

--- a/lib/igt_aux.h
+++ b/lib/igt_aux.h
@@ -46,7 +46,7 @@
 #  define gettid() (pid_t)(syscall(__NR_gettid))
 # endif
 #endif
-#define sigev_notify_thread_id _sigev_un._tid
+#define sigev_notify_thread_id sigev_notify_function

 /* auxialiary igt helpers from igt_aux.c */
 /* generally useful helpers */

--- a/lib/igt_halffloat.c
+++ b/lib/igt_halffloat.c
@@ -162,7 +162,7 @@ static inline float _half_to_float(uint16_t val)
 	return fi.f;
 }

-#if defined(__x86_64__) && !defined(__clang__)
+#if defined(__x86_64__) && !defined(__clang__) && defined(__GLIBC__)
 #pragma GCC push_options
 #pragma GCC target("f16c")

--- a/lib/igt_x86.c
+++ b/lib/igt_x86.c
@@ -190,7 +190,7 @@ char *igt_x86_features_to_string(unsigned features, char *line)
 }
 #endif

-#if defined(__x86_64__) && !defined(__clang__)
+#if defined(__x86_64__) && !defined(__clang__) && defined(__GLIBC__)
 #pragma GCC push_options
 #pragma GCC target("sse4.1")
 #pragma GCC diagnostic ignored "-Wpointer-arith"

--- /dev/null
+++ b/lib/signal_compat.h
@@ -0,0 +1,8 @@
+#define SIGEV_SIGNAL 0
+#define SIGEV_NONE 1
+#define SIGEV_THREAD 2
+
+#define SIGEV_SIGNAL    0       /* notify via signal */
+#define SIGEV_NONE      1       /* other notification: meaningless */
+#define SIGEV_THREAD    2       /* deliver via thread creation */
+#define SIGEV_THREAD_ID 4       /* deliver to thread */

--- a/tests/drm_read.c
+++ b/tests/drm_read.c
@@ -220,7 +220,7 @@ static void test_short_buffer_wakeup(int in, enum pipe pipe)
 		pthread_mutex_unlock(&w.mutex);

 		/* Give each thread a chance to sleep in drm_read() */
-		pthread_yield();
+		sched_yield();

 		/* One event should wake all threads as none consume */
 		generate_event(w.fd, pipe);

--- a/tests/kms_hdmi_inject.c
+++ b/tests/kms_hdmi_inject.c
@@ -23,7 +23,7 @@
  */

 #include "config.h"
-
+#include <limits.h>
 #include <dirent.h>

 #include "igt.h"

--- a/tests/kms_sysfs_edid_timing.c
+++ b/tests/kms_sysfs_edid_timing.c
@@ -24,6 +24,7 @@

 #include <dirent.h>
 #include <fcntl.h>
+#include <limits.h>
 #include <sys/stat.h>

 #define THRESHOLD_PER_CONNECTOR	10

--- a/tests/i915/gem_close_race.c
+++ b/tests/i915/gem_close_race.c
@@ -42,6 +42,10 @@
 #include <sys/syscall.h>
 #include "drm.h"

+#ifndef __GLIBC__
+#include "signal_compat.h"
+#endif
+
 #define OBJECT_SIZE (256 * 1024)

 #define COPY_BLT_CMD		(2<<29|0x53<<22|0x6)
@@ -51,7 +55,7 @@
 static uint32_t devid;
 static bool has_64bit_relocations;

-#define sigev_notify_thread_id _sigev_un._tid
+#define sigev_notify_thread_id sigev_notify_function

 static void selfcopy(int fd, uint32_t handle, int loops)
 {

--- a/tests/panfrost_submit.c
+++ b/tests/panfrost_submit.c
@@ -68,7 +68,7 @@
 static void check_fb(int fd, struct panfrost_bo *bo)
 {
         int gpu_prod_id = igt_panfrost_get_param(fd, DRM_PANFROST_PARAM_GPU_PROD_ID);
-        __uint32_t *fbo;
+        uint32_t *fbo;
         int i;

         fbo = bo->map;

--- a/tests/kms_atomic.c
+++ b/tests/kms_atomic.c
@@ -683,7 +683,6 @@
 {
 	int timeline, fence_fd;
 	void *map;
-	const ptrdiff_t PAGE_SIZE = sysconf(_SC_PAGE_SIZE);
 	uint64_t old_mode_id = pipe->values[IGT_CRTC_MODE_ID];

 	igt_require_sw_sync();