diff -Nru mpi-defaults-1.12/debian/changelog mpi-defaults-1.12+rpi1/debian/changelog
--- mpi-defaults-1.12/debian/changelog	2018-04-19 13:43:42.000000000 +0000
+++ mpi-defaults-1.12+rpi1/debian/changelog	2018-04-27 01:33:03.000000000 +0000
@@ -1,3 +1,9 @@
+mpi-defaults (1.12+rpi1) buster-staging; urgency=medium
+
+  * Replace broken detection with hardcoded openmpi.
+
+ -- Peter Michael Green <plugwash@raspbian.org>  Fri, 27 Apr 2018 01:33:03 +0000
+
 mpi-defaults (1.12) unstable; urgency=medium
 
   * Team upload.
diff -Nru mpi-defaults-1.12/debian/debian_defaults mpi-defaults-1.12+rpi1/debian/debian_defaults
--- mpi-defaults-1.12/debian/debian_defaults	1970-01-01 00:00:00.000000000 +0000
+++ mpi-defaults-1.12+rpi1/debian/debian_defaults	2018-04-27 01:12:29.000000000 +0000
@@ -0,0 +1,10 @@
+# Default MPI implementation on this architecture:
+ARCH_DEFAULT_MPI_IMPL=libarm-linux-gnueabihfopeninclude
+# Architectures where OpenMPI is available:
+OPENMPI_AVAILABLE_ARCHITECTURES=alpha amd64 arm64 armel armhf hppa hurd-i386 i386 ia64 kfreebsd-amd64 kfreebsd-i386 m68k mips mips64el mipsel powerpc powerpcspe ppc64 ppc64el s390x sh4 sparc64 x32
+# Architectures where MPICH is available:
+MPICH_AVAILABLE_ARCHITECTURES=alpha amd64 arm64 armel armhf hppa hurd-i386 i386 ia64 kfreebsd-amd64 kfreebsd-i386 m68k mips mips64el mipsel powerpc powerpcspe ppc64 ppc64el s390x sh4 sparc64 x32
+# Architectures defaulting to OpenMPI:
+OPENMPI_ARCHITECTURES=alpha amd64 arm64 armel armhf hppa hurd-i386 i386 ia64 kfreebsd-amd64 kfreebsd-i386 mips mips64el mipsel powerpc powerpcspe ppc64 ppc64el s390x sparc64 x32
+# Architectures defaulting to MPICH:
+MPICH_ARCHITECTURES=m68k sh4
diff -Nru mpi-defaults-1.12/debian/rules mpi-defaults-1.12+rpi1/debian/rules
--- mpi-defaults-1.12/debian/rules	2018-04-19 13:43:42.000000000 +0000
+++ mpi-defaults-1.12+rpi1/debian/rules	2018-04-27 01:32:52.000000000 +0000
@@ -5,7 +5,8 @@
 d := debian/debian_defaults
 
 # default in this architecture:
-MPI=$(shell readlink /etc/alternatives/mpi | sed s/usr//g | sed s/bin//g | sed s/mpic*\.//g | sed s/\\///g)
+#MPI=$(shell readlink /etc/alternatives/mpi | sed s/usr//g | sed s/bin//g | sed s/mpic*\.//g | sed s/\\///g)
+MPI=openmpi
 
 # availability of MPI implementations: