Fix cmake failed to build db_bench (facebook#8289)

Summary:
And change the cmake build on macos with GFLAGS on to cover more cases.

Pull Request resolved: facebook#8289

Reviewed By: zhichao-cao

Differential Revision: D28372467

Pulled By: jay-zhuang

fbshipit-source-id: ad7fbe523c3fb135ef5281adbaf2070ca5d0873d

.circleci/config.yml

@@ -138,7 +138,7 @@ jobs:
       - install-cmake-on-macos
       - install-gflags-on-macos
       - pre-steps-macos
-      - run: ulimit -S -n 1048576 && (mkdir build && cd build && cmake -DWITH_GFLAGS=0 .. && make V=1 -j32) | .circleci/cat_ignore_eagain
+      - run: ulimit -S -n 1048576 && (mkdir build && cd build && cmake -DWITH_GFLAGS=1 .. && make V=1 -j32) | .circleci/cat_ignore_eagain
       - post-steps
 
   build-linux:

CMakeLists.txt

@@ -1342,6 +1342,7 @@ endif()
 
 if(WITH_BENCHMARK_TOOLS)
   add_executable(db_bench${ARTIFACT_SUFFIX}
+    tools/simulated_hybrid_file_system.cc
     tools/db_bench.cc
     tools/db_bench_tool.cc)
   target_link_libraries(db_bench${ARTIFACT_SUFFIX}