os: resolve unused variable warning

Found by Windows tests:

    [305/1061] /home/ubuntu/ceph/build.deps/mingw-llvm/bin/x86_64-w64-mingw32-clang++ -DBOOST_ASIO_DISABLE_THREAD_KEYWORD_EXTENSION -DBOOST_ASIO_NO_TS_EXECUTORS -DFMT_HEADER_ONLY=1 -DFMT_USE_TZSET=0 -DHAVE_CONFIG_H -DWITH_KSTORE -D_FILE_OFFSET_BITS=64 -D_POSIX=1 -D_POSIX_=1 -D_POSIX_C_SOURCE=1 -D_POSIX_THREADS=1 -D_REENTRANT -D_THREAD_SAFE -D_WIN32_WINNT=0x0A00 -D__CEPH__ -D__STDC_FORMAT_MACROS -I/home/ubuntu/ceph/build/src/include -I/home/ubuntu/ceph/src -I/home/ubuntu/ceph/src/include/win32 -isystem /home/ubuntu/ceph/build.deps/mingw/boost/include -isystem /home/ubuntu/ceph/build/include -isystem /home/ubuntu/ceph/src/xxHash -isystem /home/ubuntu/ceph/src/fmt/include -isystem /home/ubuntu/ceph/src/rocksdb/include -isystem /home/ubuntu/ceph/build.deps/mingw/snappy/include -isystem /home/ubuntu/ceph/build.deps/mingw/lz4/lib -isystem /home/ubuntu/ceph/build.deps/mingw/zlib/include -g1 -O3 -DNDEBUG   -I/home/ubuntu/ceph/build.deps/mingw-llvm/x86_64-w64-mingw32/include -I/home/ubuntu/ceph/build.deps/mingw-llvm/x86_64-w64-mingw32/include -march=native -Wno-unknown-attributes -include winsock_wrapper.h -include win32_errno.h -Wall -fno-strict-aliasing -fsigned-char -Wtype-limits -Wignored-qualifiers -Wpointer-arith -Werror=format-security -Winit-self -Wno-unknown-pragmas -Wnon-virtual-dtor -Wno-ignored-qualifiers -Wsign-compare -ftemplate-depth-1024 -DBOOST_ALLOW_DEPRECATED_HEADERS -Wpessimizing-move -Wredundant-move -Wno-inconsistent-missing-override -Wno-mismatched-tags -Wno-unused-private-field -Wno-address-of-packed-member -Wno-unused-function -Wno-unused-local-typedef -Wno-varargs -Wno-gnu-designator -Wno-missing-braces -Wno-parentheses -Wno-deprecated-register -fdiagnostics-color=auto -std=c++2b -MD -MT src/os/CMakeFiles/os.dir/ObjectStore.cc.obj -MF src/os/CMakeFiles/os.dir/ObjectStore.cc.obj.d -o src/os/CMakeFiles/os.dir/ObjectStore.cc.obj -c /home/ubuntu/ceph/src/os/ObjectStore.cc
    /home/ubuntu/ceph/src/os/ObjectStore.cc:72:7: warning: unused variable 'r' [-Wunused-variable]
      int r;
          ^
    1 warning generated.

Signed-off-by: Patrick Donnelly <[email protected]>

Author: batrick

src/os/ObjectStore.cc

@@ -69,20 +69,20 @@ int ObjectStore::probe_block_device_fsid(
   const string& path,
   uuid_d *fsid)
 {
-  int r;
-
 #if defined(WITH_BLUESTORE)
   // first try bluestore -- it has a crc on its header and will fail
   // reliably.
-  r = BlueStore::get_block_device_fsid(cct, path, fsid);
+  int r = BlueStore::get_block_device_fsid(cct, path, fsid);
   if (r == 0) {
     lgeneric_dout(cct, 0) << __func__ << " " << path << " is bluestore, "
 			  << *fsid << dendl;
     return r;
+  } else {
+    return -EINVAL;
   }
-#endif
-
+#else
   return -EINVAL;
+#endif
 }
 
 int ObjectStore::write_meta(const std::string& key,