CMake 制作的 Emscripten 库不能 link
Emscripten library make from CMake cannot link
我正在使用 Grassroot Dicom 查看器版本 2.8.9 在 Windows 10 64 位平台上编译到 Emscripten 库 bc。
我遵循了这个 website
的说明
emconfigure cmake .
emmake make VERBOSE=1
之后我得到了以 .a 而不是 .bc 结尾的库文件，类似于
libgdcmcharls.a libgdcmCommon.a libgdcmDICT.a ....
当我查看每个以
开头的静态库文件的汇编代码时
！ arch./
而不是
BC
如教程中所述website注意
Some build systems may not properly emit bitcode using the above
procedure, and you may see is not valid bitcode warnings. You can run
file to check if a file contains bitcode (also you can manually check
if the contents start with BC). It is also worth running emmake make
VERBOSE=1 which will print out the commands it runs - you should see
emcc being used, and not the native system compiler. If emcc is not
used, you may need to modify the configure or cmake scripts.
我认为这是我无法生成内容以 BC 开头的库的问题，但我得到了！拱门./ ?
当然，这些文件无法从 emcc 链接（找不到引用错误）
error: undefined symbol: _ZN4gdcm11ImageReader8GetImageEv
error: undefined symbol: _ZN4gdcm11ImageReaderC1Ev
error: undefined symbol: _ZN4gdcm11ImageReaderD1Ev
error: undefined symbol: _ZN4gdcm5Trace14GetErrorStreamE
所以我根据this
修改了GDCMCMakefile.txt
if (EMSCRIPTEN)
set(CMAKE_AR "emcc" CACHE)
set(CMAKE_STATIC_LIBRARY_SUFFIX ".bc")
set(CMAKE_C_CREATE_STATIC_LIBRARY "<CMAKE_AR> -o <TARGET> <LINK_FLAGS> <OBJECTS>")
set(CMAKE_CXX_CREATE_STATIC_LIBRARY "<CMAKE_AR> -o <TARGET> <LINK_FLAGS> <OBJECTS>")
endif()
然而，这并没有什么帮助。 "make" 仍然生成 .a 库文件
我编译代码的命令如下；我还将所有 .a 文件复制到与 main.cpp
相同的文件夹中
emcc -std=c++17 -O3 -s WASM=1 -s USE_WEBGL2=1 -s FULL_ES3=1 -s ALLOW_MEMORY_GROWTH=1 -o hello.html -s "EXTRA_EXPORTED_RUNTIME_METHODS=['ccall', 'cwrap']" --no-heap-copy libgdcmcharls.a libgdcmCommon.a libgdcmDICT.a libgdcmDSED.a libgdcmexpat.a libgdcmIOD.a libgdcmjpeg12.a libgdcmjpeg16.a libgdcmjpeg8.a libgdcmMEXD.a libgdcmMSFF.a libgdcmopenjp2.a libgdcmzlib.a libgdcmuuid.a libsocketxx.a main.cpp ...........
link是我的GDCM 2.8.9库文件。使用 Windows10 编译
emcmake cmake 最后是 emmake make（基于 mingw32-make）。
这是我的 CMakeCXXCompiler.cmake 在调用 emconfigure cmake 之后。
set(CMAKE_CXX_COMPILER "C:/workspace/emsdk/emscripten/1.38.14/em++.bat")
set(CMAKE_CXX_COMPILER_ARG1 "")
set(CMAKE_CXX_COMPILER_ID "Clang")
set(CMAKE_CXX_COMPILER_VERSION "6.0.1")
set(CMAKE_CXX_COMPILER_VERSION_INTERNAL "")
set(CMAKE_CXX_COMPILER_WRAPPER "")
set(CMAKE_CXX_STANDARD_COMPUTED_DEFAULT "98")
set(CMAKE_CXX_COMPILE_FEATURES "cxx_std_98;cxx_template_template_parameters;cxx_std_11;cxx_alias_templates;cxx_alignas;cxx_alignof;cxx_attributes;cxx_auto_type;cxx_constexpr;cxx_decltype;cxx_decltype_incomplete_return_types;cxx_default_function_template_args;cxx_defaulted_functions;cxx_defaulted_move_initializers;cxx_delegating_constructors;cxx_deleted_functions;cxx_enum_forward_declarations;cxx_explicit_conversions;cxx_extended_friend_declarations;cxx_extern_templates;cxx_final;cxx_func_identifier;cxx_generalized_initializers;cxx_inheriting_constructors;cxx_inline_namespaces;cxx_lambdas;cxx_local_type_template_args;cxx_long_long_type;cxx_noexcept;cxx_nonstatic_member_init;cxx_nullptr;cxx_override;cxx_range_for;cxx_raw_string_literals;cxx_reference_qualified_functions;cxx_right_angle_brackets;cxx_rvalue_references;cxx_sizeof_member;cxx_static_assert;cxx_strong_enums;cxx_thread_local;cxx_trailing_return_types;cxx_unicode_literals;cxx_uniform_initialization;cxx_unrestricted_unions;cxx_user_literals;cxx_variadic_macros;cxx_variadic_templates;cxx_std_14;cxx_aggregate_default_initializers;cxx_attribute_deprecated;cxx_binary_literals;cxx_contextual_conversions;cxx_decltype_auto;cxx_digit_separators;cxx_generic_lambdas;cxx_lambda_init_captures;cxx_relaxed_constexpr;cxx_return_type_deduction;cxx_variable_templates;cxx_std_17")
set(CMAKE_CXX98_COMPILE_FEATURES "cxx_std_98;cxx_template_template_parameters")
set(CMAKE_CXX11_COMPILE_FEATURES "cxx_std_11;cxx_alias_templates;cxx_alignas;cxx_alignof;cxx_attributes;cxx_auto_type;cxx_constexpr;cxx_decltype;cxx_decltype_incomplete_return_types;cxx_default_function_template_args;cxx_defaulted_functions;cxx_defaulted_move_initializers;cxx_delegating_constructors;cxx_deleted_functions;cxx_enum_forward_declarations;cxx_explicit_conversions;cxx_extended_friend_declarations;cxx_extern_templates;cxx_final;cxx_func_identifier;cxx_generalized_initializers;cxx_inheriting_constructors;cxx_inline_namespaces;cxx_lambdas;cxx_local_type_template_args;cxx_long_long_type;cxx_noexcept;cxx_nonstatic_member_init;cxx_nullptr;cxx_override;cxx_range_for;cxx_raw_string_literals;cxx_reference_qualified_functions;cxx_right_angle_brackets;cxx_rvalue_references;cxx_sizeof_member;cxx_static_assert;cxx_strong_enums;cxx_thread_local;cxx_trailing_return_types;cxx_unicode_literals;cxx_uniform_initialization;cxx_unrestricted_unions;cxx_user_literals;cxx_variadic_macros;cxx_variadic_templates")
set(CMAKE_CXX14_COMPILE_FEATURES "cxx_std_14;cxx_aggregate_default_initializers;cxx_attribute_deprecated;cxx_binary_literals;cxx_contextual_conversions;cxx_decltype_auto;cxx_digit_separators;cxx_generic_lambdas;cxx_lambda_init_captures;cxx_relaxed_constexpr;cxx_return_type_deduction;cxx_variable_templates")
set(CMAKE_CXX17_COMPILE_FEATURES "")
set(CMAKE_CXX20_COMPILE_FEATURES "")
set(CMAKE_CXX_PLATFORM_ID "emscripten")
set(CMAKE_CXX_SIMULATE_ID "")
set(CMAKE_CXX_SIMULATE_VERSION "")
set(CMAKE_AR "C:/workspace/emsdk/emscripten/1.38.14/emar.bat")
set(CMAKE_CXX_COMPILER_AR "C:/Program Files/LLVM/bin/llvm-ar.exe")
set(CMAKE_RANLIB "C:/workspace/emsdk/emscripten/1.38.14/emranlib.bat")
set(CMAKE_CXX_COMPILER_RANLIB "C:/Program Files/LLVM/bin/llvm-ranlib.exe")
set(CMAKE_LINKER "C:/Program Files/LLVM/bin/wasm-ld.exe")
set(CMAKE_COMPILER_IS_GNUCXX )
set(CMAKE_CXX_COMPILER_LOADED 1)
set(CMAKE_CXX_COMPILER_WORKS TRUE)
set(CMAKE_CXX_ABI_COMPILED )
set(CMAKE_COMPILER_IS_MINGW )
set(CMAKE_COMPILER_IS_CYGWIN )
if(CMAKE_COMPILER_IS_CYGWIN)
set(CYGWIN 1)
set(UNIX 1)
endif()
set(CMAKE_CXX_COMPILER_ENV_VAR "CXX")
if(CMAKE_COMPILER_IS_MINGW)
set(MINGW 1)
endif()
set(CMAKE_CXX_COMPILER_ID_RUN 1)
set(CMAKE_CXX_IGNORE_EXTENSIONS inl;h;hpp;HPP;H;o;O;obj;OBJ;def;DEF;rc;RC)
set(CMAKE_CXX_SOURCE_FILE_EXTENSIONS C;M;c++;cc;cpp;cxx;mm;CPP)
set(CMAKE_CXX_LINKER_PREFERENCE 30)
set(CMAKE_CXX_LINKER_PREFERENCE_PROPAGATES 1)
# Save compiler ABI information.
set(CMAKE_CXX_SIZEOF_DATA_PTR "4")
set(CMAKE_CXX_COMPILER_ABI "")
set(CMAKE_CXX_LIBRARY_ARCHITECTURE "")
if(CMAKE_CXX_SIZEOF_DATA_PTR)
set(CMAKE_SIZEOF_VOID_P "${CMAKE_CXX_SIZEOF_DATA_PTR}")
endif()
if(CMAKE_CXX_COMPILER_ABI)
set(CMAKE_INTERNAL_PLATFORM_ABI "${CMAKE_CXX_COMPILER_ABI}")
endif()
if(CMAKE_CXX_LIBRARY_ARCHITECTURE)
set(CMAKE_LIBRARY_ARCHITECTURE "")
endif()
set(CMAKE_CXX_CL_SHOWINCLUDES_PREFIX "")
if(CMAKE_CXX_CL_SHOWINCLUDES_PREFIX)
set(CMAKE_CL_SHOWINCLUDES_PREFIX "${CMAKE_CXX_CL_SHOWINCLUDES_PREFIX}")
endif()
set(CMAKE_CXX_IMPLICIT_LINK_LIBRARIES "")
set(CMAKE_CXX_IMPLICIT_LINK_DIRECTORIES "")
set(CMAKE_CXX_IMPLICIT_LINK_FRAMEWORK_DIRECTORIES "")
终于找到问题了。从命令生成的库；
emconfigure cmake .
即使我看到编译器使用 em++.bat 作为编译器，也不兼容 emcc。
如何发现问题。
我用一个叫"Hex Editor Neo"的程序打开库文件（只用小库文件测试，大库文件程序崩溃）。
如果与emcc不兼容使用。前几个字符将是！ arch 这行不通。 cmake生成错误的库文件见下图；
确保你有如下图所示的BC；
但是如何做到这一点
你不能只使用
emconfigure cmake . <---------- wrong
您需要通过以下命令添加一个选项来生成位码 (.bc)
emconfigure cmake . -DEMSCRIPTEN_GENERATE_BITCODE_STATIC_LIBRARIES=1
然后会生成所有.bc结尾的库文件，这些库文件可以用emcc链接
我正在使用 Grassroot Dicom 查看器版本 2.8.9 在 Windows 10 64 位平台上编译到 Emscripten 库 bc。
我遵循了这个 website
的说明emconfigure cmake .
emmake make VERBOSE=1
之后我得到了以 .a 而不是 .bc 结尾的库文件，类似于
libgdcmcharls.a libgdcmCommon.a libgdcmDICT.a ....
当我查看每个以
开头的静态库文件的汇编代码时！ arch./
而不是
BC
如教程中所述website注意
Some build systems may not properly emit bitcode using the above procedure, and you may see is not valid bitcode warnings. You can run file to check if a file contains bitcode (also you can manually check if the contents start with BC). It is also worth running emmake make VERBOSE=1 which will print out the commands it runs - you should see emcc being used, and not the native system compiler. If emcc is not used, you may need to modify the configure or cmake scripts.
我认为这是我无法生成内容以 BC 开头的库的问题，但我得到了！拱门./ ?
当然，这些文件无法从 emcc 链接（找不到引用错误）
error: undefined symbol: _ZN4gdcm11ImageReader8GetImageEv
error: undefined symbol: _ZN4gdcm11ImageReaderC1Ev
error: undefined symbol: _ZN4gdcm11ImageReaderD1Ev
error: undefined symbol: _ZN4gdcm5Trace14GetErrorStreamE
所以我根据this
修改了GDCMCMakefile.txtif (EMSCRIPTEN)
set(CMAKE_AR "emcc" CACHE)
set(CMAKE_STATIC_LIBRARY_SUFFIX ".bc")
set(CMAKE_C_CREATE_STATIC_LIBRARY "<CMAKE_AR> -o <TARGET> <LINK_FLAGS> <OBJECTS>")
set(CMAKE_CXX_CREATE_STATIC_LIBRARY "<CMAKE_AR> -o <TARGET> <LINK_FLAGS> <OBJECTS>")
endif()
然而，这并没有什么帮助。 "make" 仍然生成 .a 库文件
我编译代码的命令如下；我还将所有 .a 文件复制到与 main.cpp
相同的文件夹中emcc -std=c++17 -O3 -s WASM=1 -s USE_WEBGL2=1 -s FULL_ES3=1 -s ALLOW_MEMORY_GROWTH=1 -o hello.html -s "EXTRA_EXPORTED_RUNTIME_METHODS=['ccall', 'cwrap']" --no-heap-copy libgdcmcharls.a libgdcmCommon.a libgdcmDICT.a libgdcmDSED.a libgdcmexpat.a libgdcmIOD.a libgdcmjpeg12.a libgdcmjpeg16.a libgdcmjpeg8.a libgdcmMEXD.a libgdcmMSFF.a libgdcmopenjp2.a libgdcmzlib.a libgdcmuuid.a libsocketxx.a main.cpp ...........
link是我的GDCM 2.8.9库文件。使用 Windows10 编译 emcmake cmake 最后是 emmake make（基于 mingw32-make）。
这是我的 CMakeCXXCompiler.cmake 在调用 emconfigure cmake 之后。
set(CMAKE_CXX_COMPILER "C:/workspace/emsdk/emscripten/1.38.14/em++.bat")
set(CMAKE_CXX_COMPILER_ARG1 "")
set(CMAKE_CXX_COMPILER_ID "Clang")
set(CMAKE_CXX_COMPILER_VERSION "6.0.1")
set(CMAKE_CXX_COMPILER_VERSION_INTERNAL "")
set(CMAKE_CXX_COMPILER_WRAPPER "")
set(CMAKE_CXX_STANDARD_COMPUTED_DEFAULT "98")
set(CMAKE_CXX_COMPILE_FEATURES "cxx_std_98;cxx_template_template_parameters;cxx_std_11;cxx_alias_templates;cxx_alignas;cxx_alignof;cxx_attributes;cxx_auto_type;cxx_constexpr;cxx_decltype;cxx_decltype_incomplete_return_types;cxx_default_function_template_args;cxx_defaulted_functions;cxx_defaulted_move_initializers;cxx_delegating_constructors;cxx_deleted_functions;cxx_enum_forward_declarations;cxx_explicit_conversions;cxx_extended_friend_declarations;cxx_extern_templates;cxx_final;cxx_func_identifier;cxx_generalized_initializers;cxx_inheriting_constructors;cxx_inline_namespaces;cxx_lambdas;cxx_local_type_template_args;cxx_long_long_type;cxx_noexcept;cxx_nonstatic_member_init;cxx_nullptr;cxx_override;cxx_range_for;cxx_raw_string_literals;cxx_reference_qualified_functions;cxx_right_angle_brackets;cxx_rvalue_references;cxx_sizeof_member;cxx_static_assert;cxx_strong_enums;cxx_thread_local;cxx_trailing_return_types;cxx_unicode_literals;cxx_uniform_initialization;cxx_unrestricted_unions;cxx_user_literals;cxx_variadic_macros;cxx_variadic_templates;cxx_std_14;cxx_aggregate_default_initializers;cxx_attribute_deprecated;cxx_binary_literals;cxx_contextual_conversions;cxx_decltype_auto;cxx_digit_separators;cxx_generic_lambdas;cxx_lambda_init_captures;cxx_relaxed_constexpr;cxx_return_type_deduction;cxx_variable_templates;cxx_std_17")
set(CMAKE_CXX98_COMPILE_FEATURES "cxx_std_98;cxx_template_template_parameters")
set(CMAKE_CXX11_COMPILE_FEATURES "cxx_std_11;cxx_alias_templates;cxx_alignas;cxx_alignof;cxx_attributes;cxx_auto_type;cxx_constexpr;cxx_decltype;cxx_decltype_incomplete_return_types;cxx_default_function_template_args;cxx_defaulted_functions;cxx_defaulted_move_initializers;cxx_delegating_constructors;cxx_deleted_functions;cxx_enum_forward_declarations;cxx_explicit_conversions;cxx_extended_friend_declarations;cxx_extern_templates;cxx_final;cxx_func_identifier;cxx_generalized_initializers;cxx_inheriting_constructors;cxx_inline_namespaces;cxx_lambdas;cxx_local_type_template_args;cxx_long_long_type;cxx_noexcept;cxx_nonstatic_member_init;cxx_nullptr;cxx_override;cxx_range_for;cxx_raw_string_literals;cxx_reference_qualified_functions;cxx_right_angle_brackets;cxx_rvalue_references;cxx_sizeof_member;cxx_static_assert;cxx_strong_enums;cxx_thread_local;cxx_trailing_return_types;cxx_unicode_literals;cxx_uniform_initialization;cxx_unrestricted_unions;cxx_user_literals;cxx_variadic_macros;cxx_variadic_templates")
set(CMAKE_CXX14_COMPILE_FEATURES "cxx_std_14;cxx_aggregate_default_initializers;cxx_attribute_deprecated;cxx_binary_literals;cxx_contextual_conversions;cxx_decltype_auto;cxx_digit_separators;cxx_generic_lambdas;cxx_lambda_init_captures;cxx_relaxed_constexpr;cxx_return_type_deduction;cxx_variable_templates")
set(CMAKE_CXX17_COMPILE_FEATURES "")
set(CMAKE_CXX20_COMPILE_FEATURES "")
set(CMAKE_CXX_PLATFORM_ID "emscripten")
set(CMAKE_CXX_SIMULATE_ID "")
set(CMAKE_CXX_SIMULATE_VERSION "")
set(CMAKE_AR "C:/workspace/emsdk/emscripten/1.38.14/emar.bat")
set(CMAKE_CXX_COMPILER_AR "C:/Program Files/LLVM/bin/llvm-ar.exe")
set(CMAKE_RANLIB "C:/workspace/emsdk/emscripten/1.38.14/emranlib.bat")
set(CMAKE_CXX_COMPILER_RANLIB "C:/Program Files/LLVM/bin/llvm-ranlib.exe")
set(CMAKE_LINKER "C:/Program Files/LLVM/bin/wasm-ld.exe")
set(CMAKE_COMPILER_IS_GNUCXX )
set(CMAKE_CXX_COMPILER_LOADED 1)
set(CMAKE_CXX_COMPILER_WORKS TRUE)
set(CMAKE_CXX_ABI_COMPILED )
set(CMAKE_COMPILER_IS_MINGW )
set(CMAKE_COMPILER_IS_CYGWIN )
if(CMAKE_COMPILER_IS_CYGWIN)
set(CYGWIN 1)
set(UNIX 1)
endif()
set(CMAKE_CXX_COMPILER_ENV_VAR "CXX")
if(CMAKE_COMPILER_IS_MINGW)
set(MINGW 1)
endif()
set(CMAKE_CXX_COMPILER_ID_RUN 1)
set(CMAKE_CXX_IGNORE_EXTENSIONS inl;h;hpp;HPP;H;o;O;obj;OBJ;def;DEF;rc;RC)
set(CMAKE_CXX_SOURCE_FILE_EXTENSIONS C;M;c++;cc;cpp;cxx;mm;CPP)
set(CMAKE_CXX_LINKER_PREFERENCE 30)
set(CMAKE_CXX_LINKER_PREFERENCE_PROPAGATES 1)
# Save compiler ABI information.
set(CMAKE_CXX_SIZEOF_DATA_PTR "4")
set(CMAKE_CXX_COMPILER_ABI "")
set(CMAKE_CXX_LIBRARY_ARCHITECTURE "")
if(CMAKE_CXX_SIZEOF_DATA_PTR)
set(CMAKE_SIZEOF_VOID_P "${CMAKE_CXX_SIZEOF_DATA_PTR}")
endif()
if(CMAKE_CXX_COMPILER_ABI)
set(CMAKE_INTERNAL_PLATFORM_ABI "${CMAKE_CXX_COMPILER_ABI}")
endif()
if(CMAKE_CXX_LIBRARY_ARCHITECTURE)
set(CMAKE_LIBRARY_ARCHITECTURE "")
endif()
set(CMAKE_CXX_CL_SHOWINCLUDES_PREFIX "")
if(CMAKE_CXX_CL_SHOWINCLUDES_PREFIX)
set(CMAKE_CL_SHOWINCLUDES_PREFIX "${CMAKE_CXX_CL_SHOWINCLUDES_PREFIX}")
endif()
set(CMAKE_CXX_IMPLICIT_LINK_LIBRARIES "")
set(CMAKE_CXX_IMPLICIT_LINK_DIRECTORIES "")
set(CMAKE_CXX_IMPLICIT_LINK_FRAMEWORK_DIRECTORIES "")
终于找到问题了。从命令生成的库；
emconfigure cmake .
即使我看到编译器使用 em++.bat 作为编译器，也不兼容 emcc。
如何发现问题。
我用一个叫"Hex Editor Neo"的程序打开库文件（只用小库文件测试，大库文件程序崩溃）。
如果与emcc不兼容使用。前几个字符将是！ arch 这行不通。 cmake生成错误的库文件见下图；
确保你有如下图所示的BC；
但是如何做到这一点
你不能只使用
emconfigure cmake . <---------- wrong
您需要通过以下命令添加一个选项来生成位码 (.bc)
emconfigure cmake . -DEMSCRIPTEN_GENERATE_BITCODE_STATIC_LIBRARIES=1
然后会生成所有.bc结尾的库文件，这些库文件可以用emcc链接