diff --git a/include/boost/config/compiler/sunpro_cc.hpp b/include/boost/config/compiler/sunpro_cc.hpp
index c43767f2..8f07e0e9 100644
--- a/include/boost/config/compiler/sunpro_cc.hpp
+++ b/include/boost/config/compiler/sunpro_cc.hpp
@@ -170,6 +170,13 @@
 #if !defined(__cpp_variable_templates) || (__cpp_variable_templates < 201304)
 #  define BOOST_NO_CXX14_VARIABLE_TEMPLATES
 #endif
+
+// Turn on threading support for Solaris 12.
+// Ticket #11972
+#if (__SUNPRO_CC >= 0x5140) && defined(__SunOS_5_12) && !defined(BOOST_HAS_THREADS)
+# define BOOST_HAS_THREADS
+#endif
+
 //
 // Version
 //