Use alignas for alignment.

Change-Id: I427c407a188682a360c74b2bd5a44dd62551ea66
diff --git a/liblog/tests/liblog_benchmark.cpp b/liblog/tests/liblog_benchmark.cpp
index 01fb50f..1b66a56 100644
--- a/liblog/tests/liblog_benchmark.cpp
+++ b/liblog/tests/liblog_benchmark.cpp
@@ -205,7 +205,7 @@
         android_log_header_t header;
         android_log_event_int_t payload;
     };
-    char buf[sizeof(struct packet) + 8] __aligned(8);
+    alignas(8) char buf[sizeof(struct packet) + 8];
     memset(buf, 0, sizeof(buf));
     struct packet *buffer = (struct packet*)(((uintptr_t)buf + 7) & ~7);
     if (((uintptr_t)&buffer->pmsg_header) & 7) {
@@ -281,7 +281,7 @@
         android_log_header_t header;
         android_log_event_int_t payload;
     };
-    char buf[sizeof(struct packet) + 8] __aligned(8);
+    alignas(8) char buf[sizeof(struct packet) + 8];
     memset(buf, 0, sizeof(buf));
     struct packet *buffer = (struct packet*)((((uintptr_t)buf + 7) & ~7) + 1);
     if ((((uintptr_t)&buffer->pmsg_header) & 7) != 1) {
@@ -357,7 +357,7 @@
         android_log_header_t header;
         android_log_event_int_t payload;
     };
-    char buf[sizeof(struct packet) + 8 + LOGGER_ENTRY_MAX_PAYLOAD] __aligned(8);
+    alignas(8) char buf[sizeof(struct packet) + 8 + LOGGER_ENTRY_MAX_PAYLOAD];
     memset(buf, 0, sizeof(buf));
     struct packet *buffer = (struct packet*)(((uintptr_t)buf + 7) & ~7);
     if (((uintptr_t)&buffer->pmsg_header) & 7) {
@@ -430,7 +430,7 @@
         android_log_header_t header;
         android_log_event_int_t payload;
     };
-    char buf[sizeof(struct packet) + 8 + LOGGER_ENTRY_MAX_PAYLOAD] __aligned(8);
+    alignas(8) char buf[sizeof(struct packet) + 8 + LOGGER_ENTRY_MAX_PAYLOAD];
     memset(buf, 0, sizeof(buf));
     struct packet *buffer = (struct packet*)((((uintptr_t)buf + 7) & ~7) + 1);
     if ((((uintptr_t)&buffer->pmsg_header) & 7) != 1) {