C++ 版本的问题。

[okman334]

C++版本只有一个头文件，而头文件里面有个静态变量IdGenerator *IdGenerator::instance，如果在多个模块下#include "IdGenerator.h"，会出现重复定义吧。应该把IdGenerator *IdGenerator::instance = NULL放到到cpp文件里面才比较符合工程上应用吧。

[rinace43]

老哥怎么样这样定义影响功能吗

[coalooball]

这个问题我也遇到了

(lysk-python) somnambulatory@somnambulatorys-Mac-mini FileWhisperer % cmake --build build  
[9/11] Linking CXX executable tests/hello_test
FAILED: tests/hello_test tests/hello_test[1]_tests.cmake /Users/somnambulatory/opt/FileWhisperer/build/tests/hello_test[1]_tests.cmake 
: && /Library/Developer/CommandLineTools/usr/bin/c++ -O3 -DNDEBUG -arch arm64 -isysroot /Library/Developer/CommandLineTools/SDKs/MacOSX13.3.sdk -Wl,-search_paths_first -Wl,-headerpad_max_install_names  tests/CMakeFiles/hello_test.dir/test_utils.cc.o tests/CMakeFiles/hello_test.dir/hello_test.cc.o tests/CMakeFiles/hello_test.dir/mime_type_test.cc.o tests/CMakeFiles/hello_test.dir/url_extract_test.cc.o tests/CMakeFiles/hello_test.dir/qrcode_extract_test.cc.o tests/CMakeFiles/hello_test.dir/html_test.cc.o -o tests/hello_test  file_whisper_lib/libfile_whisper_lib.a  vcpkg_installed/arm64-osx/lib/manual-link/libgtest_main.a  vcpkg_installed/arm64-osx/debug/lib/libssl.a  vcpkg_installed/arm64-osx/debug/lib/libcrypto.a  -ldl  vcpkg_installed/arm64-osx/lib/libmagic.a  vcpkg_installed/arm64-osx/lib/libicudata.a  vcpkg_installed/arm64-osx/lib/libicuuc.a  vcpkg_installed/arm64-osx/lib/libicui18n.a  vcpkg_installed/arm64-osx/lib/libicuio.a  vcpkg_installed/arm64-osx/lib/libre2.a  vcpkg_installed/arm64-osx/lib/libspdlog.a  vcpkg_installed/arm64-osx/lib/libfmt.a  -force_load  vcpkg_installed/arm64-osx/lib/libicudata.a  vcpkg_installed/arm64-osx/lib/libbit7z64.a  vcpkg_installed/arm64-osx/lib/lib7zip.a  vcpkg_installed/arm64-osx/lib/libopencv_highgui4.a  vcpkg_installed/arm64-osx/lib/libopencv_ml4.a  vcpkg_installed/arm64-osx/lib/libopencv_objdetect4.a  vcpkg_installed/arm64-osx/lib/libquirc.a  vcpkg_installed/arm64-osx/lib/libopencv_photo4.a  vcpkg_installed/arm64-osx/lib/libopencv_stitching4.a  vcpkg_installed/arm64-osx/lib/libopencv_video4.a  vcpkg_installed/arm64-osx/lib/libopencv_calib3d4.a  vcpkg_installed/arm64-osx/lib/libopencv_dnn4.a  vcpkg_installed/arm64-osx/lib/libprotobuf.a  vcpkg_installed/arm64-osx/lib/libabsl_log_internal_check_op.a  vcpkg_installed/arm64-osx/lib/libabsl_flags_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_flags_marshalling.a  vcpkg_installed/arm64-osx/lib/libabsl_flags_reflection.a  vcpkg_installed/arm64-osx/lib/libabsl_flags_config.a  vcpkg_installed/arm64-osx/lib/libabsl_flags_program_name.a  vcpkg_installed/arm64-osx/lib/libabsl_flags_private_handle_accessor.a  vcpkg_installed/arm64-osx/lib/libabsl_flags_commandlineflag.a  vcpkg_installed/arm64-osx/lib/libabsl_flags_commandlineflag_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_leak_check.a  vcpkg_installed/arm64-osx/lib/libabsl_die_if_null.a  vcpkg_installed/arm64-osx/lib/libabsl_log_internal_conditions.a  vcpkg_installed/arm64-osx/lib/libabsl_log_internal_message.a  vcpkg_installed/arm64-osx/lib/libabsl_log_internal_nullguard.a  vcpkg_installed/arm64-osx/lib/libabsl_examine_stack.a  vcpkg_installed/arm64-osx/lib/libabsl_log_internal_format.a  vcpkg_installed/arm64-osx/lib/libabsl_log_internal_proto.a  vcpkg_installed/arm64-osx/lib/libabsl_log_internal_log_sink_set.a  vcpkg_installed/arm64-osx/lib/libabsl_log_sink.a  vcpkg_installed/arm64-osx/lib/libabsl_log_entry.a  vcpkg_installed/arm64-osx/lib/libabsl_log_initialize.a  vcpkg_installed/arm64-osx/lib/libabsl_log_internal_globals.a  vcpkg_installed/arm64-osx/lib/libabsl_log_globals.a  vcpkg_installed/arm64-osx/lib/libabsl_vlog_config_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_log_internal_fnmatch.a  vcpkg_installed/arm64-osx/lib/libabsl_raw_hash_set.a  vcpkg_installed/arm64-osx/lib/libabsl_hash.a  vcpkg_installed/arm64-osx/lib/libabsl_city.a  vcpkg_installed/arm64-osx/lib/libabsl_low_level_hash.a  vcpkg_installed/arm64-osx/lib/libabsl_hashtablez_sampler.a  vcpkg_installed/arm64-osx/lib/libabsl_random_distributions.a  vcpkg_installed/arm64-osx/lib/libabsl_random_seed_sequences.a  vcpkg_installed/arm64-osx/lib/libabsl_random_internal_pool_urbg.a  vcpkg_installed/arm64-osx/lib/libabsl_random_internal_randen.a  vcpkg_installed/arm64-osx/lib/libabsl_random_internal_randen_hwaes.a  vcpkg_installed/arm64-osx/lib/libabsl_random_internal_randen_hwaes_impl.a  vcpkg_installed/arm64-osx/lib/libabsl_random_internal_randen_slow.a  vcpkg_installed/arm64-osx/lib/libabsl_random_internal_platform.a  vcpkg_installed/arm64-osx/lib/libabsl_random_internal_seed_material.a  vcpkg_installed/arm64-osx/lib/libabsl_random_seed_gen_exception.a  vcpkg_installed/arm64-osx/lib/libabsl_statusor.a  vcpkg_installed/arm64-osx/lib/libabsl_bad_variant_access.a  vcpkg_installed/arm64-osx/lib/libabsl_status.a  vcpkg_installed/arm64-osx/lib/libabsl_cord.a  vcpkg_installed/arm64-osx/lib/libabsl_bad_optional_access.a  vcpkg_installed/arm64-osx/lib/libabsl_cordz_info.a  vcpkg_installed/arm64-osx/lib/libabsl_cord_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_cordz_functions.a  vcpkg_installed/arm64-osx/lib/libabsl_exponential_biased.a  vcpkg_installed/arm64-osx/lib/libabsl_cordz_handle.a  vcpkg_installed/arm64-osx/lib/libabsl_synchronization.a  vcpkg_installed/arm64-osx/lib/libabsl_graphcycles_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_kernel_timeout_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_stacktrace.a  vcpkg_installed/arm64-osx/lib/libabsl_symbolize.a  vcpkg_installed/arm64-osx/lib/libabsl_malloc_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_debugging_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_demangle_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_demangle_rust.a  vcpkg_installed/arm64-osx/lib/libabsl_decode_rust_punycode.a  vcpkg_installed/arm64-osx/lib/libabsl_utf8_for_code_point.a  vcpkg_installed/arm64-osx/lib/libabsl_time.a  vcpkg_installed/arm64-osx/lib/libabsl_civil_time.a  vcpkg_installed/arm64-osx/lib/libabsl_time_zone.a  -Wl,-framework,CoreFoundation  vcpkg_installed/arm64-osx/lib/libabsl_crc_cord_state.a  vcpkg_installed/arm64-osx/lib/libabsl_crc32c.a  vcpkg_installed/arm64-osx/lib/libabsl_str_format_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_crc_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_crc_cpu_detect.a  vcpkg_installed/arm64-osx/lib/libabsl_strerror.a  vcpkg_installed/arm64-osx/lib/libutf8_validity.a  vcpkg_installed/arm64-osx/lib/libabsl_strings.a  vcpkg_installed/arm64-osx/lib/libabsl_int128.a  vcpkg_installed/arm64-osx/lib/libabsl_strings_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_string_view.a  vcpkg_installed/arm64-osx/lib/libabsl_base.a  vcpkg_installed/arm64-osx/lib/libabsl_spinlock_wait.a  vcpkg_installed/arm64-osx/lib/libabsl_throw_delegate.a  vcpkg_installed/arm64-osx/lib/libabsl_raw_logging_internal.a  vcpkg_installed/arm64-osx/lib/libabsl_log_severity.a  vcpkg_installed/arm64-osx/lib/libopencv_features2d4.a  vcpkg_installed/arm64-osx/lib/libopencv_flann4.a  vcpkg_installed/arm64-osx/lib/libopencv_videoio4.a  vcpkg_installed/arm64-osx/lib/libopencv_imgcodecs4.a  vcpkg_installed/arm64-osx/lib/libjpeg.a  vcpkg_installed/arm64-osx/lib/libwebpdecoder.a  vcpkg_installed/arm64-osx/lib/libwebp.a  vcpkg_installed/arm64-osx/lib/libwebpdemux.a  vcpkg_installed/arm64-osx/lib/libwebpmux.a  vcpkg_installed/arm64-osx/lib/libsharpyuv.a  vcpkg_installed/arm64-osx/lib/libpng16.a  vcpkg_installed/arm64-osx/lib/libtiff.a  vcpkg_installed/arm64-osx/lib/liblzma.a  vcpkg_installed/arm64-osx/lib/libjpeg.a  vcpkg_installed/arm64-osx/lib/libwebpdecoder.a  vcpkg_installed/arm64-osx/lib/libwebp.a  vcpkg_installed/arm64-osx/lib/libwebpdemux.a  vcpkg_installed/arm64-osx/lib/libwebpmux.a  vcpkg_installed/arm64-osx/lib/libsharpyuv.a  vcpkg_installed/arm64-osx/lib/libpng16.a  vcpkg_installed/arm64-osx/lib/libtiff.a  vcpkg_installed/arm64-osx/lib/liblzma.a  -lm  -framework AppKit  vcpkg_installed/arm64-osx/lib/libopencv_imgproc4.a  vcpkg_installed/arm64-osx/lib/libopencv_core4.a  vcpkg_installed/arm64-osx/lib/libz.a  vcpkg_installed/arm64-osx/lib/manual-link/opencv4_thirdparty/libtegra_hal.a  -framework Cocoa  -framework Accelerate  -framework AVFoundation  -framework CoreGraphics  -framework CoreMedia  -framework CoreVideo  -framework QuartzCore  vcpkg_installed/arm64-osx/lib/libgumbo.a  vcpkg_installed/arm64-osx/lib/libgtest.a && cd /Users/somnambulatory/opt/FileWhisperer/build/tests && /opt/homebrew/Cellar/cmake/3.29.2/bin/cmake -D TEST_TARGET=hello_test -D TEST_EXECUTABLE=/Users/somnambulatory/opt/FileWhisperer/build/tests/hello_test -D TEST_EXECUTOR= -D TEST_WORKING_DIR=/Users/somnambulatory/opt/FileWhisperer/build/tests -D TEST_EXTRA_ARGS= -D TEST_PROPERTIES= -D TEST_PREFIX= -D TEST_SUFFIX= -D TEST_FILTER= -D NO_PRETTY_TYPES=FALSE -D NO_PRETTY_VALUES=FALSE -D TEST_LIST=hello_test_TESTS -D CTEST_FILE=/Users/somnambulatory/opt/FileWhisperer/build/tests/hello_test[1]_tests.cmake -D TEST_DISCOVERY_TIMEOUT=5 -D TEST_XML_OUTPUT_DIR= -P /opt/homebrew/Cellar/cmake/3.29.2/share/cmake/Modules/GoogleTestAddTests.cmake
duplicate symbol 'idgen::IdGenerator::instance' in:
    tests/CMakeFiles/hello_test.dir/mime_type_test.cc.o
    file_whisper_lib/libfile_whisper_lib.a(common.cc.o)
duplicate symbol 'idgen::IdGenerator::instance' in:
    tests/CMakeFiles/hello_test.dir/mime_type_test.cc.o
    file_whisper_lib/libfile_whisper_lib.a(extractor.cc.o)
duplicate symbol 'idgen::IdGenerator::instance' in:
    tests/CMakeFiles/hello_test.dir/mime_type_test.cc.o
    tests/CMakeFiles/hello_test.dir/url_extract_test.cc.o
duplicate symbol 'idgen::IdGenerator::instance' in:
    tests/CMakeFiles/hello_test.dir/mime_type_test.cc.o
    tests/CMakeFiles/hello_test.dir/html_test.cc.o
duplicate symbol 'idgen::IdGenerator::instance' in:
    tests/CMakeFiles/hello_test.dir/mime_type_test.cc.o
    tests/CMakeFiles/hello_test.dir/qrcode_extract_test.cc.o
ld: 5 duplicate symbols for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
[10/11] Building CXX object CMakeFiles/FileWhisperer.dir/src/server.cc.o
ninja: build stopped: subcommand failed.
(lysk-python) somnambulatory@somnambulatorys-Mac-mini FileWhisperer %