diff --git a/cmake/cross_compiling/android.cmake b/cmake/cross_compiling/android.cmake
index 25081671477edc67dcb0f6f9b3a2f2f2e13c0fb6..9724c16122ab2e6be55864c8716698c9b9d7c3f0 100644
--- a/cmake/cross_compiling/android.cmake
+++ b/cmake/cross_compiling/android.cmake
@@ -129,19 +129,8 @@ IF("${CMAKE_VERSION}" VERSION_LESS "3.7.0")
         MESSAGE(FATAL_ERROR "Cannot find CXX compiler: ${ANDROID_CXX_COMPILER}")
     ENDIF()
 
-    # Fortran compiler
-    IF(NOT CMAKE_Fortran_COMPILER)
-        SET(ANDROID_Fortran_COMPILER "${ANDROID_TOOLCHAIN_PREFIX}gfortran")
-    ELSE()
-        GET_FILENAME_COMPONENT(ANDROID_Fortran_COMPILER ${CMAKE_Fortran_COMPILER})
-    ENDIF()
-    IF(NOT EXISTS ${ANDROID_Fortran_COMPILER})
-        SET(ANDROID_Fortran_COMPILER "")
-    ENDIF()
-
     SET(CMAKE_C_COMPILER ${ANDROID_C_COMPILER} CACHE PATH "C compiler" FORCE)
     SET(CMAKE_CXX_COMPILER ${ANDROID_CXX_COMPILER} CACHE PATH "CXX compiler" FORCE)
-    SET(CMAKE_Fortran_COMPILER ${ANDROID_Fortran_COMPILER} CACHE PATH "Fortran compiler" FORCE)
 
     # Toolchain and ABI specific flags.
     SET(ANDROID_COMPILER_FLAGS "-ffunction-sections -fdata-sections -finline-limit=64")
diff --git a/cmake/cross_compiling/raspberry_pi.cmake b/cmake/cross_compiling/raspberry_pi.cmake
index bfd26f130c1e7863532c8a3e3ca7661fc91c4f67..817b39f6833e37c340d4ee465048480cfc3db151 100644
--- a/cmake/cross_compiling/raspberry_pi.cmake
+++ b/cmake/cross_compiling/raspberry_pi.cmake
@@ -73,19 +73,8 @@ IF(NOT EXISTS ${RPI_CXX_COMPILER})
     MESSAGE(FATAL_ERROR "Cannot find CXX compiler: ${RPI_CXX_COMPILER}")
 ENDIF()
 
-# Fortran compiler
-IF(NOT CMAKE_Fortran_COMPILER)
-    SET(RPI_Fortran_COMPILER "${RPI_TOOLCHAIN_PREFIX}gfortran")
-ELSE()
-    GET_FILENAME_COMPONENT(RPI_Fortran_COMPILER ${CMAKE_Fortran_COMPILER} PROGRAM)
-ENDIF()
-IF(NOT EXISTS RPI_Fortran_COMPILER)
-    SET(RPI_Fortran_COMPILER "")
-ENDIF()
-
 SET(CMAKE_C_COMPILER ${RPI_C_COMPILER} CACHE PATH "C compiler" FORCE)
 SET(CMAKE_CXX_COMPILER ${RPI_CXX_COMPILER} CACHE PATH "CXX compiler" FORCE)
-SET(CMAKE_Fortran_COMPILER ${RPI_Fortran_COMPILER} CACHE PATH "Fortran compiler" FORCE)
 
 IF(RPI_ARM_NEON)
     SET(RPI_C_FLAGS "${RPI_C_FLAGS} -mfpu=neon")
diff --git a/cmake/external/protobuf.cmake b/cmake/external/protobuf.cmake
index 3e417f123b5f668988c6469f76ae6dc3caa421f6..994ba14cfa0044ee0d87d5c9ede4bd32fbe0e4f4 100644
--- a/cmake/external/protobuf.cmake
+++ b/cmake/external/protobuf.cmake
@@ -76,7 +76,6 @@ FUNCTION(build_protobuf TARGET_NAME BUILD_FOR_HOST)
 ENDFUNCTION()
 
 IF(NOT CMAKE_CROSSCOMPILING)
-    SET(PROTOBUF_VERSION 3.1)
     FIND_PACKAGE(Protobuf ${PROTOBUF_VERSION})
 
     IF(PROTOBUF_FOUND)
@@ -92,6 +91,7 @@ ELSE()
         CACHE FILEPATH "protobuf executable." FORCE)
 ENDIF()
 
+SET(PROTOBUF_VERSION 3.1)
 IF(NOT PROTOBUF_FOUND)
     build_protobuf(protobuf FALSE)
     SET(PROTOBUF_INCLUDE_DIR ${protobuf_INCLUDE_DIR}