Merge pull request #6359 from markrtuttle/cmake-on-big-sur-arm2

Build with /usr/bin/clang on MacOS

Author: NlightNFotis

CMakeLists.txt

@@ -1,5 +1,15 @@
 cmake_minimum_required(VERSION 3.2)
 
+# Compile with /usr/bin/clang on MacOS
+# See https://github.com/diffblue/cbmc/issues/4956
+#
+if (CMAKE_HOST_SYSTEM_NAME STREQUAL Darwin)
+    if(NOT DEFINED CMAKE_C_COMPILER)
+        message(STATUS "Setting CMAKE_C_COMPILER to /usr/bin/clang for MacOS")
+        set(CMAKE_C_COMPILER "/usr/bin/clang")
+    endif()
+endif()
+
 # If cmake generates files inside of the cbmc source directory this can lead to important files being overwritten, so we prevent that here
 if("${CMAKE_BINARY_DIR}" STREQUAL "${CMAKE_SOURCE_DIR}")
   message(FATAL_ERROR