Type mismatch warnings in XCode iOS project about benchmark HOT 4 CLOSED

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 480d8a5..d46c0dd 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -33,6 +33,7 @@ endif()

 # Turn compiler warnings up to 11
 include(AddCXXCompilerFlag)
+add_cxx_compiler_flag(-Wshorten-64-to-32)
 add_cxx_compiler_flag(-Wall)
 add_cxx_compiler_flag(-Wshadow)
 add_cxx_compiler_flag(-Werror)

[ 50%] Building CXX object src/CMakeFiles/benchmark.dir/benchmark.cc.o
In file included from /usr/local/src/benchmark/src/benchmark.cc:15:
/usr/local/src/benchmark/include/benchmark/benchmark.h:230:35: error: implicit conversion loses integer precision: 'const int64_t' (aka 'const long long') to 'int' [-Werror,-Wshorten-64-to-32]
  int iterations() const { return total_iterations_; }
                           ~~~~~~ ^~~~~~~~~~~~~~~~~
/usr/local/src/benchmark/src/benchmark.cc:119:23: error: implicit conversion loses integer precision: 'unsigned long' to 'int' [-Werror,-Wshorten-64-to-32]
        *exponent = i + 1;
                  ~ ~~^~~
/usr/local/src/benchmark/src/benchmark.cc:133:24: error: implicit conversion loses integer precision: 'unsigned long' to 'int' [-Werror,-Wshorten-64-to-32]
        *exponent = -i - 1;
                  ~ ~~~^~~
/usr/local/src/benchmark/src/benchmark.cc:351:14: error: implicit conversion loses integer precision: 'size_t' (aka 'unsigned long') to 'int' [-Werror,-Wshorten-64-to-32]
      return index;
      ~~~~~~ ^~~~~
/usr/local/src/benchmark/src/benchmark.cc:354:15: error: implicit conversion loses integer precision: 'size_type' (aka 'unsigned long') to 'int' [-Werror,-Wshorten-64-to-32]
  int index = families_.size();
      ~~~~~   ^~~~~~~~~~~~~~~~
/usr/local/src/benchmark/src/benchmark.cc:397:54: error: implicit conversion loses integer precision: 'size_t' (aka 'unsigned long') to 'int' [-Werror,-Wshorten-64-to-32]
        instances = family->CreateBenchmarkInstances(x, Benchmark::kNoRange);
                    ~~~~~~                           ^
/usr/local/src/benchmark/src/benchmark.cc:404:56: error: implicit conversion loses integer precision: 'size_t' (aka 'unsigned long') to 'int' [-Werror,-Wshorten-64-to-32]
          instances = family->CreateBenchmarkInstances(x, y);
                      ~~~~~~                           ^
/usr/local/src/benchmark/src/benchmark.cc:404:59: error: implicit conversion loses integer precision: 'size_t' (aka 'unsigned long') to 'int' [-Werror,-Wshorten-64-to-32]
          instances = family->CreateBenchmarkInstances(x, y);
                      ~~~~~~                              ^
/usr/local/src/benchmark/src/benchmark.cc:1239:65: error: implicit conversion loses integer precision: 'unsigned long' to 'const int' [-Werror,-Wshorten-64-to-32]
          std::max<int>(name_field_width, benchmark.name.size() + 17);
          ~~~                             ~~~~~~~~~~~~~~~~~~~~~~^~~~
/usr/local/src/benchmark/src/benchmark.cc:1242:65: error: implicit conversion loses integer precision: 'unsigned long' to 'const int' [-Werror,-Wshorten-64-to-32]
          std::max<int>(name_field_width, benchmark.name.size() + 10);
          ~~~                             ~~~~~~~~~~~~~~~~~~~~~~^~~~
/usr/local/src/benchmark/src/benchmark.cc:1245:65: error: implicit conversion loses integer precision: 'unsigned long' to 'const int' [-Werror,-Wshorten-64-to-32]
          std::max<int>(name_field_width, benchmark.name.size() + 7);
          ~~~                             ~~~~~~~~~~~~~~~~~~~~~~^~~
/usr/local/src/benchmark/src/benchmark.cc:1247:58: error: implicit conversion loses integer precision: 'size_type' (aka 'unsigned long') to 'const int' [-Werror,-Wshorten-64-to-32]
      name_field_width = std::max<int>(name_field_width, benchmark.name.size());
                         ~~~                             ^~~~~~~~~~~~~~~~~~~~~
12 errors generated.
make[2]: *** [src/CMakeFiles/benchmark.dir/benchmark.cc.o] Error 1

../../3rdparty/benchmark/src/sleep.cc:30:36: error: implicit conversion loses integer precision: 'long long' to '__darwin_time_t' (aka 'long') [-Werror,-Wshorten-64-to-32]
  sleep_time.tv_sec = microseconds / kNumMicrosPerSecond;
                    ~ ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~