diff --git a/Modules/CMakeCXXCompilerId.cpp.in b/Modules/CMakeCXXCompilerId.cpp.in
index 3a334ed471..2a92287e07 100644
--- a/Modules/CMakeCXXCompilerId.cpp.in
+++ b/Modules/CMakeCXXCompilerId.cpp.in
@@ -66,6 +66,12 @@ char const *info_cray = "INFO" ":" "compiler_wrapper[CrayPrgEnv]";
 #  else
 #    define CXX_STD __cplusplus
 #  endif
+#elif (defined(__IBMCPP__) || defined(__ibmxl__)) && defined(__linux__)
+#  if __cplusplus == CXX_STD_11 && defined(__cpp_aggregate_nsdmi)
+#    define CXX_STD CXX_STD_14
+#  else
+#    define CXX_STD __cplusplus
+#  endif
 #else
 #  define CXX_STD __cplusplus
 #endif
diff --git a/Tests/CompileFeatures/default_dialect.cpp b/Tests/CompileFeatures/default_dialect.cpp
index 82a8698c37..081b049a34 100644
--- a/Tests/CompileFeatures/default_dialect.cpp
+++ b/Tests/CompileFeatures/default_dialect.cpp
@@ -35,6 +35,12 @@ struct Outputter;
 #  else
 #    define CXX_STD __cplusplus
 #  endif
+#elif (defined(__IBMCPP__) || defined(__ibmxl__)) && defined(__linux__)
+#  if __cplusplus == CXX_STD_11 && defined(__cpp_aggregate_nsdmi)
+#    define CXX_STD CXX_STD_14
+#  else
+#    define CXX_STD __cplusplus
+#  endif
 #else
 #  define CXX_STD __cplusplus
 #endif