From: Matthias Maier <tamiko@43-1.org>
Date: Fri, 20 Nov 2015 19:34:16 +0000 (-0600)
Subject: CMake: Compatibility fixes for CMake 3.4.0
X-Git-Tag: v8.4.0-rc2~214^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F1890%2Fhead;p=dealii.git

CMake: Compatibility fixes for CMake 3.4.0

CMake 3.4.0 no longer exports MPI_<LANGUAGE>_COMPILER as cached variable.
Therefore, we also have to make sure to unset ordinary variables (in
addition to cached variables) for our "retry" pass.
---

diff --git a/cmake/modules/FindMPI.cmake b/cmake/modules/FindMPI.cmake
index 1a8d0be9df..4e45a53bd8 100644
--- a/cmake/modules/FindMPI.cmake
+++ b/cmake/modules/FindMPI.cmake
@@ -80,6 +80,9 @@ IF(NOT MPI_CXX_FOUND AND DEAL_II_WITH_MPI)
     )
   # Clear variables so that FIND_PACKAGE runs again:
   SET(MPI_FOUND)
+  SET(MPI_CXX_COMPILER)
+  SET(MPI_C_COMPILER)
+  SET(MPI_Fortran_COMPILER)
   UNSET(MPI_CXX_COMPILER CACHE)
   UNSET(MPI_C_COMPILER CACHE)
   UNSET(MPI_Fortran_COMPILER CACHE)