diff --git a/include/occa/mpi.hpp b/include/occa/mpi.hpp
index 718c49830..ee93e8356 100644
--- a/include/occa/mpi.hpp
+++ b/include/occa/mpi.hpp
@@ -4,6 +4,9 @@
 #  ifndef OCCA_MPI_HEADER
 #  define OCCA_MPI_HEADER
 
+// Workaround for https://github.com/open-mpi/ompi/issues/5157
+#define OMPI_SKIP_MPICXX 1
+
 #include <mpi.h>
 #include <vector>
 
diff --git a/src/tools/sys.cpp b/src/tools/sys.cpp
index 29c766999..8b5130b6a 100644
--- a/src/tools/sys.cpp
+++ b/src/tools/sys.cpp
@@ -13,7 +13,6 @@
 #  include <sys/types.h>
 #  include <sys/stat.h>
 #  include <sys/syscall.h>
-#  include <sys/sysctl.h>
 #  include <sys/time.h>
 #  include <unistd.h>
 #  if (OCCA_OS & OCCA_LINUX_OS)
@@ -21,6 +20,7 @@
 #    include <sys/sysinfo.h>
 #  else // OCCA_MACOS_OS
 #    include <mach/mach_host.h>
+#    include <sys/sysctl.h>
 #    ifdef __clang__
 #      include <CoreServices/CoreServices.h>
 #      include <mach/mach_time.h>