Index: openmp/trunk/README.rst
===================================================================
--- openmp/trunk/README.rst
+++ openmp/trunk/README.rst
@@ -191,8 +191,11 @@
   Align certain data structures on 4096-byte.  This option is useful on
   multi-node systems where a small ``CACHE_LINE`` setting leads to false sharing.
 
-**LIBOMP_OMPT_SUPPORT** = ``OFF|ON``
-  Include support for the OpenMP Tools Interface (OMPT).
+**LIBOMP_OMPT_SUPPORT** = ``ON|OFF``
+  Include support for the OpenMP Tools Interface (OMPT). 
+  This option is supported and ``ON`` by default for x86, x86_64, AArch64, and 
+  PPC64 on Linux, Windows, and mac OS.
+  This option is ``OFF`` if this feature is not supported for the platform.
 
 **LIBOMP_OMPT_OPTIONAL** = ``ON|OFF``
   Include support for optional OMPT functionality.  This option is ignored if
Index: openmp/trunk/runtime/CMakeLists.txt
===================================================================
--- openmp/trunk/runtime/CMakeLists.txt
+++ openmp/trunk/runtime/CMakeLists.txt
@@ -299,12 +299,17 @@
   set (LIBOMP_USE_VERSION_SYMBOLS FALSE)
 endif()
 
-# OMPT-support
+# OMPT-support defaults to ON for OpenMP 5.0+ and if the requirements in
+# cmake/config-ix.cmake are fulfilled.
+set(OMPT_DEFAULT FALSE)
+if ((${LIBOMP_OMP_VERSION} GREATER 49) AND (LIBOMP_HAVE_OMPT_SUPPORT))
+  set(OMPT_DEFAULT TRUE)
+endif()
+set(LIBOMP_OMPT_SUPPORT ${OMPT_DEFAULT} CACHE BOOL
+  "OMPT-support?")
+
 set(LIBOMP_OMPT_DEBUG FALSE CACHE BOOL
   "Trace OMPT initialization?")
-#after testing: turn on ompt support by default for OpenMP 5.0 and higher
-set(LIBOMP_OMPT_SUPPORT FALSE CACHE BOOL
-  "OMPT-support?")
 set(LIBOMP_OMPT_OPTIONAL TRUE CACHE BOOL
   "OMPT-optional?")
 if(LIBOMP_OMPT_SUPPORT AND (NOT LIBOMP_HAVE_OMPT_SUPPORT))
Index: openmp/trunk/runtime/cmake/config-ix.cmake
===================================================================
--- openmp/trunk/runtime/cmake/config-ix.cmake
+++ openmp/trunk/runtime/cmake/config-ix.cmake
@@ -236,7 +236,15 @@
 if(NOT LIBOMP_HAVE___BUILTIN_FRAME_ADDRESS)
   set(LIBOMP_HAVE_OMPT_SUPPORT FALSE)
 else()
-  if((WIN32 AND LIBOMP_HAVE_PSAPI) OR APPLE OR (NOT WIN32 AND LIBOMP_HAVE_WEAK_ATTRIBUTE))
+  if( # hardware architecture supported?
+     ((LIBOMP_ARCH STREQUAL x86_64) OR
+      (LIBOMP_ARCH STREQUAL i386) OR
+#      (LIBOMP_ARCH STREQUAL arm) OR
+      (LIBOMP_ARCH STREQUAL aarch64) OR
+      (LIBOMP_ARCH STREQUAL ppc64le) OR
+      (LIBOMP_ARCH STREQUAL ppc64))
+     AND # OS supported?
+     ((WIN32 AND LIBOMP_HAVE_PSAPI) OR APPLE OR (NOT WIN32 AND LIBOMP_HAVE_WEAK_ATTRIBUTE)))
     set(LIBOMP_HAVE_OMPT_SUPPORT TRUE)
   else()
     set(LIBOMP_HAVE_OMPT_SUPPORT FALSE)