diff --git a/projects/clr/rocclr/runtime/os/os_posix.cpp b/projects/clr/rocclr/runtime/os/os_posix.cpp
index 9b7e33e317..3617d36d05 100644
--- a/projects/clr/rocclr/runtime/os/os_posix.cpp
+++ b/projects/clr/rocclr/runtime/os/os_posix.cpp
@@ -394,6 +394,36 @@ bool Os::isThreadAlive(const Thread& thread) {
   return ::pthread_kill((pthread_t)thread.handle(), 0) == 0;
 }
 
+static size_t tlsSize = 0;
+
+// Try to guess the size of TLS (plus some frames)
+void* guessTlsSizeThread(void* param) {
+  address stackBase;
+  address currentFrame;
+  size_t stackSize;
+  Os::currentStackInfo(&stackBase, &stackSize);
+  currentFrame = reinterpret_cast<address>(&stackSize);
+  tlsSize = stackBase - currentFrame;
+  // align up to page boundary
+  tlsSize = alignUp(tlsSize, amd::Os::pageSize());
+  return NULL;
+}
+
+static void guessTlsSize(void) {
+  int retval;
+  pthread_t handle;
+  pthread_attr_t threadAttr;
+
+  ::pthread_attr_init(&threadAttr);
+  retval = ::pthread_create(&handle, &threadAttr, guessTlsSizeThread, NULL);
+  if (retval == 0) {
+    pthread_join(handle, NULL);
+  } else {
+    fatal("pthread_create() failed with default stack size");
+  }
+  ::pthread_attr_destroy(&threadAttr);
+}
+
 const void* Os::createOsThread(amd::Thread* thread) {
   pthread_attr_t threadAttr;
   ::pthread_attr_init(&threadAttr);
@@ -403,7 +433,10 @@ const void* Os::createOsThread(amd::Thread* thread) {
     if (0 != ::pthread_attr_getguardsize(&threadAttr, &guardsize)) {
       fatal("pthread_attr_getguardsize() failed");
     }
-    ::pthread_attr_setstacksize(&threadAttr, thread->stackSize_ + guardsize);
+
+    static std::once_flag initOnce;
+    std::call_once(initOnce, guessTlsSize);
+    ::pthread_attr_setstacksize(&threadAttr, thread->stackSize_ + guardsize + tlsSize);
   }
 
   // We never plan the use join, so free the resources now.