diff --git a/CMakeLists.txt b/CMakeLists.txt
index 47c2e823..3127e4fb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -80,6 +80,9 @@ endif()
 
 # MPI CONFIG OPTIONS. Defaults are set for generic MPI desktop.
 if (EKAT_ENABLE_MPI)
+  if (APPLE)
+    message(FATAL_ERROR "EKAT does not support MPI on Apple machines")
+  endif()
   set(EKAT_MPIRUN_EXE "mpiexec" CACHE STRING "The executable name for mpirun")
   set(EKAT_MPI_EXTRA_ARGS "--bind-to core" CACHE STRING "Options for mpirun")
   set(EKAT_MPI_NP_FLAG "--map-by" CACHE STRING "The mpirun flag for designating the total number of ranks")
diff --git a/src/core/ekat_fpe.cpp b/src/core/ekat_fpe.cpp
index c4e0e710..f8a3d60c 100644
--- a/src/core/ekat_fpe.cpp
+++ b/src/core/ekat_fpe.cpp
@@ -3,6 +3,26 @@
 #include <cfenv>
 
 #ifndef EKAT_HAVE_FEENABLEEXCEPT
+#ifdef __APPLE__
+// Apple Silicon has a very different floating point environment, which we leave for
+// future exploration.
+
+inline int fegetexcept (void)
+{
+  return 0;
+}
+
+inline int feenableexcept (int excepts)
+{
+  return 0;
+}
+
+inline int fedisableexcept (int excepts)
+{
+  return 0;
+}
+
+#else
 
 // Drop-in replacement of some useful GNU utils (needed on Apple platforms)
 inline int fegetexcept (void)
@@ -44,7 +64,8 @@ inline int fedisableexcept (int excepts)
   return ( fesetenv (&fenv) ? -1 : old_excepts );
 }
 
-#endif // EKAT_NEEDS_FEENABLEEXCEPT
+#endif // #ifndef __APPLE__
+#endif // #ifndef EKAT_HAVE_FEENABLEEXCEPT
 
 namespace ekat {
 
diff --git a/tests/core/CMakeLists.txt b/tests/core/CMakeLists.txt
index 2692d860..be30d896 100644
--- a/tests/core/CMakeLists.txt
+++ b/tests/core/CMakeLists.txt
@@ -45,10 +45,12 @@ EkatCreateUnitTestFromExec(catch_main_invalid_flags regress_fail
 )
 
 # Comm tests
-EkatCreateUnitTest(comm comm.cpp
-  LIBS ekat::Core
-  MPI_RANKS 1 ${EKAT_TEST_MAX_RANKS}
-)
+if (EKAT_ENABLE_MPI)
+  EkatCreateUnitTest(comm comm.cpp
+    LIBS ekat::Core
+    MPI_RANKS 1 ${EKAT_TEST_MAX_RANKS}
+  )
+endif()
 
 # Test units framework
 EkatCreateUnitTest(units units.cpp