Index: cmake/modules/HandleLLVMOptions.cmake
===================================================================
--- cmake/modules/HandleLLVMOptions.cmake
+++ cmake/modules/HandleLLVMOptions.cmake
@@ -234,7 +234,7 @@
 
 # If building on a GNU specific 32-bit system, make sure off_t is 64 bits
 # so that off_t can stored offset > 2GB
-if( CMAKE_SIZEOF_VOID_P EQUAL 4 )
+if( CMAKE_SIZEOF_VOID_P EQUAL 4 AND (NOT LLVM_FORCE_SMALLFILE) )
   add_definitions( -D_LARGEFILE_SOURCE )
   add_definitions( -D_FILE_OFFSET_BITS=64 )
 endif()
@@ -303,13 +303,13 @@
     # especially so std::equal(nullptr, nullptr, nullptr) will not assert.
     add_definitions("-D_DEBUG_POINTER_IMPL=")
   endif()
-  
+
   include(ChooseMSVCCRT)
 
   if( MSVC11 )
     add_definitions(-D_VARIADIC_MAX=10)
   endif()
-  
+
   # Add definitions that make MSVC much less annoying.
   add_definitions(
     # For some reason MS wants to deprecate a bunch of standard functions...
@@ -370,7 +370,7 @@
 
       string(FIND "${upper_exe_flags} ${upper_module_flags} ${upper_shared_flags}"
         "/INCREMENTAL" linker_flag_idx)
-      
+
       if (${linker_flag_idx} GREATER -1)
         message(WARNING "/Brepro not compatible with /INCREMENTAL linking - builds will be non-deterministic")
       else()