diff --git a/bench/async_bench.cpp b/bench/async_bench.cpp
index ce2c9281..cf4d9754 100644
--- a/bench/async_bench.cpp
+++ b/bench/async_bench.cpp
@@ -162,7 +162,7 @@ void thread_fun(std::shared_ptr<spdlog::logger> logger, int howmany)
 void bench_mt(int howmany, std::shared_ptr<spdlog::logger> logger, int thread_count)
 {
     using std::chrono::high_resolution_clock;
-    vector<thread> threads;
+    vector<std::thread> threads;
     auto start = high_resolution_clock::now();
 
     int msgs_per_thread = howmany / thread_count;
diff --git a/include/spdlog/details/os-inl.h b/include/spdlog/details/os-inl.h
index 0575d811..a7cd37f7 100644
--- a/include/spdlog/details/os-inl.h
+++ b/include/spdlog/details/os-inl.h
@@ -46,7 +46,7 @@
 #        include <sys/syscall.h> //Use gettid() syscall under linux to get thread id
 
 #    elif defined(_AIX)
-#        include <pthread.h> // for pthread_getthreadid_np
+#        include <pthread.h> // for pthread_getthrds_np
 
 #    elif defined(__DragonFly__) || defined(__FreeBSD__)
 #        include <pthread_np.h> // for pthread_getthreadid_np
@@ -230,8 +230,8 @@ SPDLOG_INLINE size_t filesize(FILE *f)
 #    endif
 
 #else // unix
-// OpenBSD doesn't compile with :: before the fileno(..)
-#    if defined(__OpenBSD__)
+// OpenBSD and AIX doesn't compile with :: before the fileno(..)
+#    if defined(__OpenBSD__) || defined(_AIX)
     int fd = fileno(f);
 #    else
     int fd = ::fileno(f);
@@ -336,7 +336,14 @@ SPDLOG_INLINE size_t _thread_id() SPDLOG_NOEXCEPT
 #        define SYS_gettid __NR_gettid
 #    endif
     return static_cast<size_t>(::syscall(SYS_gettid));
-#elif defined(_AIX) || defined(__DragonFly__) || defined(__FreeBSD__)
+#elif defined(_AIX)
+    struct __pthrdsinfo buf;
+    int reg_size = 0;
+    pthread_t pt = pthread_self();
+    int retval = pthread_getthrds_np(&pt, PTHRDSINFO_QUERY_TID, &buf, sizeof(buf), NULL, &reg_size);
+    int tid = (!retval) ? buf.__pi_tid : 0;
+    return static_cast<size_t>(tid);
+#elif defined(__DragonFly__) || defined(__FreeBSD__)
     return static_cast<size_t>(::pthread_getthreadid_np());
 #elif defined(__NetBSD__)
     return static_cast<size_t>(::_lwp_self());