Error: cannot find -lgflags while building glog

[gaurav16gupta]

I am building glog for Android NDK. Getting this error while building-

[ 91%] Building CXX object CMakeFiles/stl_logging_unittest.dir/src/stl_logging_unittest.cc.o
/home/gaurav/deeplearning/caffe-android-lib/glog/src/logging_unittest.cc:641:3: error: #error There is no way to do glob.

error There is no way to do glob.

^
Linking CXX executable symbolize_unittest
cc1plus: warning: unrecognized command line option "-Wno-unnamed-type-template-args"
make[2]: *** [CMakeFiles/logging_unittest.dir/src/logging_unittest.cc.o] Error 1
make[1]: *** [CMakeFiles/logging_unittest.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
/home/gaurav/Android/Sdk/ndk-bundle/toolchains/aarch64-linux-android-4.9/prebuilt/linux-x86_64/bin/../lib/gcc/aarch64-linux-android/4.9.x/../../../../aarch64-linux-android/bin/ld: cannot find -lgflags
collect2: error: ld returned 1 exit status
make[2]: *** [symbolize_unittest] Error 1
make[1]: *** [CMakeFiles/symbolize_unittest.dir/all] Error 2
Linking CXX executable demangle_unittest
/home/gaurav/Android/Sdk/ndk-bundle/toolchains/aarch64-linux-android-4.9/prebuilt/linux-x86_64/bin/../lib/gcc/aarch64-linux-android/4.9.x/../../../../aarch64-linux-android/bin/ld: cannot find -lgflags
collect2: error: ld returned 1 exit status
make[2]: *** [demangle_unittest] Error 1
make[1]: *** [CMakeFiles/demangle_unittest.dir/all] Error 2
Linking CXX executable stl_logging_unittest
/home/gaurav/Android/Sdk/ndk-bundle/toolchains/aarch64-linux-android-4.9/prebuilt/linux-x86_64/bin/../lib/gcc/aarch64-linux-android/4.9.x/../../../../aarch64-linux-android/bin/ld: cannot find -lgflags
collect2: error: ld returned 1 exit status
make[2]: *** [stl_logging_unittest] Error 1
make[1]: *** [CMakeFiles/stl_logging_unittest.dir/all] Error 2
make: *** [all] Error 2

Any suggestion?

[sh1r0]

Hi @stark123, please provide more details about how you built. Did you build gflags first?

[gaurav16gupta]

Yes, the gflags is build first.
Also I am getting this warning-

CMake Warning:
Manually-specified variables were not used by the project:
GFLAGS_INCLUDE_DIR
GFLAGS_LIBRARY

[sh1r0]

I did not get such warnings when building via scripts/build_glog.sh.

[sh1r0]

Could be reopened if needed.

[xuepan01]

Hi @stark123, I met the same issue with you.
Actually here is two issues:

1. Cannot find the gflags lib to link, this can be resolved by:
   a. Create a file as Findgflags.cmake in the glog/cmake folder.
   b. Add two line in the file:
   set(gflags_INCLUDE_DIR ${GFLAGS_INCLUDE_DIR})
   set(gflags_LIBRARIES ${GFLAGS_LIBRARY})
   Now the issue should be resolved.
2. error There is no way to do glob
   This is caused by BUILD_TESTING is defined but cannot find glob.h.
   I cannot find where defines the BUILD_TESTING, but it seems it's only a unit test, you can remove the test in the CMakeList.txt or comment the error in the logging_unittest.cc if you don't care about the test.