From 3595c0b21a1faaefc16a85bc21e54fc26d9ae937 Mon Sep 17 00:00:00 2001
From: Greg Sjaardema <gsjaardema@gmail.com>
Date: Wed, 12 Oct 2022 07:01:43 -0600
Subject: [PATCH] Use c++17 fallthrough; remove unused fallthrough

---
 packages/seacas/applications/nem_slice/elb.h              | 4 +++-
 .../seacas/applications/nem_spread/pe_write_parExo_info.C | 8 +++++---
 packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.C   | 6 ------
 3 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/packages/seacas/applications/nem_slice/elb.h b/packages/seacas/applications/nem_slice/elb.h
index 183f0c5f77..cf754e36eb 100644
--- a/packages/seacas/applications/nem_slice/elb.h
+++ b/packages/seacas/applications/nem_slice/elb.h
@@ -37,7 +37,9 @@
 
 #define MAX_INP_LINE 10240
 
-#if defined(__GNUC__) && __GNUC__ >= 7 && !__INTEL_COMPILER
+#if (__cplusplus >= 201703L)
+#define FALL_THROUGH [[fallthrough]]
+#elif defined(__GNUC__) && __GNUC__ >= 7 && !__INTEL_COMPILER
 #define FALL_THROUGH [[gnu::fallthrough]]
 #else
 #define FALL_THROUGH ((void)0)
diff --git a/packages/seacas/applications/nem_spread/pe_write_parExo_info.C b/packages/seacas/applications/nem_spread/pe_write_parExo_info.C
index e07afc7308..092e2c21c2 100644
--- a/packages/seacas/applications/nem_spread/pe_write_parExo_info.C
+++ b/packages/seacas/applications/nem_spread/pe_write_parExo_info.C
@@ -1,5 +1,5 @@
 /*
- * Copyright(C) 1999-2021 National Technology & Engineering Solutions
+ * Copyright(C) 1999-2022 National Technology & Engineering Solutions
  * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
  * NTESS, the U.S. Government retains certain rights in this software.
  *
@@ -26,11 +26,13 @@
 template <typename INT> struct ELEM_COMM_MAP;
 template <typename INT> struct NODE_COMM_MAP;
 
-#if defined(__GNUC__) && __GNUC__ >= 7 && !__INTEL_COMPILER
+#if (__cplusplus >= 201703L)
+#define FALL_THROUGH [[fallthrough]]
+#elif defined(__GNUC__) && __GNUC__ >= 7 && !__INTEL_COMPILER
 #define FALL_THROUGH [[gnu::fallthrough]]
 #else
 #define FALL_THROUGH ((void)0)
-#endif /* __GNUC__ >= 7 */
+#endif
 
 namespace {
   template <typename INT>
diff --git a/packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.C b/packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.C
index 07416a4237..280de25182 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.C
@@ -33,12 +33,6 @@
 
 #define DO_TIMING 0
 
-#if defined(__GNUC__) && __GNUC__ >= 7 && !__INTEL_COMPILER
-#define FALL_THROUGH [[gnu::fallthrough]]
-#else
-#define FALL_THROUGH ((void)0)
-#endif /* __GNUC__ >= 7 */
-
 namespace {
   template <typename T> void generate_index(std::vector<T> &index)
   {