From: Matthias Maier <tamiko@43-1.org>
Date: Wed, 2 May 2018 14:35:48 +0000 (-0500)
Subject: CMake: Fix MPI version detection, round two
X-Git-Tag: v9.0.0-rc1~42^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F6424%2Fhead;p=dealii.git

CMake: Fix MPI version detection, round two
---

diff --git a/cmake/modules/FindMPI.cmake b/cmake/modules/FindMPI.cmake
index 8a899213c5..cbe43f7f13 100644
--- a/cmake/modules/FindMPI.cmake
+++ b/cmake/modules/FindMPI.cmake
@@ -109,6 +109,20 @@ IF(NOT MPI_MPI_H MATCHES "-NOTFOUND" AND NOT DEFINED MPI_VERSION)
     MPI_VERSION_MINOR "${MPI_VERSION_MINOR_STRING}"
     )
   SET(MPI_VERSION "${MPI_VERSION_MAJOR}.${MPI_VERSION_MINOR}")
+
+  #
+  # Except - this doesn't always work. Some distributions install a header
+  # stub mpi.h that includes the right mpi header depending on the
+  # architecture. In this case we are really out of luck. It is not
+  # straightforward to find the correct header file to query the version
+  # information from. Just set a very conservative default:
+  #
+  IF(MPI_VERSION STREQUAL ".")
+    SET(MPI_VERSION "0.0")
+    SET(MPI_VERSION_MAJOR "0")
+    SET(MPI_VERSION_MINOR "0")
+  ENDIF()
+
 ENDIF()
 
 DEAL_II_PACKAGE_HANDLE(MPI