Building shared libraries on Windows fails

The setup in the README_SETUP.md does not work.

See doc/Install_develop.rst

How to build on Windows
~~~~~~~~~~~~~~~~~~~~~~~

We use `Visual Studio
2019 <https://visualstudio.microsoft.com/de/vs/features/cplusplus/>`__
as compiler. We use `cmake <https://cmake.org/download/>`__ as build
tool.

1. clone/update the subrepo ``git submodule update --init proto``
2. ``mkdir build``
3. ``cd build``
4. ``conan install .. -g visual_studio -s arch=x86_64 -s build_type=Release -s compiler.toolset=v142 -s compiler.version=16 -s compiler.runtime=MD --build=missing --update``
5. ``cmake -B . ..``
6. open ``libcaosdb.sln`` with Visual Studio, change the buildtype to
   ``Release`` and build the project. (You can open Tools/Command
   Line/Developer Command Prompt and execute
   ``msbuild libcaosdb.sln /property:Configuration=Release``)

assigned to @timm

added BugConfirmed label

added S1 label

assigned to @joschaschmiedt and unassigned @timm

changed iteration to Sprint Apr 15, 2024 - Apr 28, 2024

added Statustodo label

added (B BugUnconfirmed labels and removed BugConfirmed label

set weight to 2

removed iteration Sprint Apr 15, 2024 - Apr 28, 2024

changed iteration to Sprint Apr 29, 2024 - May 12, 2024

@timm, do you remember what kind of error is meant here? Is #74 (closed) familiar to you?

Note about gRPC in Windows DLLs from https://github.com/grpc/grpc/blob/master/BUILDING.md#windows-a-note-on-building-shared-libs-dlls

Windows DLL build is supported at a "best effort" basis and we don't recommend using gRPC C++ as a DLL as there are some known drawbacks around how C++ DLLs work on Windows. For example, there is no stable C++ ABI and you can't safely allocate memory in one DLL, and free it in another etc.

That said, we don't actively prohibit building DLLs on windows (it can be enabled in cmake with -DBUILD_SHARED_LIBS=ON), and are free to use the DLL builds at your own risk.

you've been warned that there are some important drawbacks and some things might not work at all or will be broken in interesting ways.

we don't have extensive testing for DLL builds in place (to avoid maintenance costs, increased test duration etc.) so regressions / build breakages might occur

This may or may not be related to the issues for libcaosdb/liblinkahead

created branch f-34-building-shared-libraries-on-windows-fails to address this issue

removed iteration Sprint Apr 29, 2024 - May 12, 2024

changed iteration to Sprint May 13, 2024 - May 26, 2024

I get a linker error at build:

LINK : fatal error LNK1181: cannot open input file 'stdc++fs.lib'

According to e.g. here msvc doesn't use stdc++fs and it needs to be removed from the linker input.

stdc++fs was a temporary libstdc++ library which doesn't exist in visual studio

changed the description

Manually removing stdc++fs.lib from the linker input gets rid of the linker error and the caosdb project and cxxcaosdbcli compiles sucessfully. We need to find out out, which canon/cmake settings causes stdc++fs.lib to appear in the linker input.

However, the ccaosdb project still fails with several unresolved symbol errors:

1>------ Build started: Project: ccaosdb, Configuration: Release x64 ------
1>Auto build dll exports
1>   Creating library C:/Code/LinkAhead/linkahead-cpplib/build/lib/ccaosdb.lib and object C:/Code/LinkAhead/linkahead-cpplib/build/lib/ccaosdb.exp
1>ccaosdb.obj : error LNK2019: unresolved external symbol "struct caosdb::entity::v1::ListDataTypeDefaultTypeInternal caosdb::entity::v1::_ListDataType_default_instance_" (?_ListDataType_default_instance_@v1@entity@caosdb@@3UListDataTypeDefaultTypeInternal@123@A) referenced in function caosdb_entity_datatype_get_datatype_name
1>ccaosdb.obj : error LNK2019: unresolved external symbol "struct caosdb::entity::v1::PropertyDefaultTypeInternal caosdb::entity::v1::_Property_default_instance_" (?_Property_default_instance_@v1@entity@caosdb@@3UPropertyDefaultTypeInternal@123@A) referenced in function "public: __cdecl caosdb::entity::Property::Property(class caosdb::entity::v1::Property *)" (??0Property@entity@caosdb@@QEAA@PEAV0v1@12@@Z)
1>ccaosdb.obj : error LNK2019: unresolved external symbol "struct caosdb::entity::v1::ReferenceDataTypeDefaultTypeInternal caosdb::entity::v1::_ReferenceDataType_default_instance_" (?_ReferenceDataType_default_instance_@v1@entity@caosdb@@3UReferenceDataTypeDefaultTypeInternal@123@A) referenced in function caosdb_entity_datatype_get_datatype_name
1>ccaosdb.obj : error LNK2019: unresolved external symbol "struct caosdb::entity::v1::ScalarValueDefaultTypeInternal caosdb::entity::v1::_ScalarValue_default_instance_" (?_ScalarValue_default_instance_@v1@entity@caosdb@@3UScalarValueDefaultTypeInternal@123@A) referenced in function "public: virtual bool __cdecl caosdb::entity::Value::GetAsBool(void)const " (?GetAsBool@Value@entity@caosdb@@UEBA_NXZ)
1>ccaosdb.obj : error LNK2019: unresolved external symbol "struct caosdb::entity::v1::VersionDefaultTypeInternal caosdb::entity::v1::_Version_default_instance_" (?_Version_default_instance_@v1@entity@caosdb@@3UVersionDefaultTypeInternal@123@A) referenced in function caosdb_entity_entity_get_version_id
1>C:\Code\LinkAhead\linkahead-cpplib\build\bin\ccaosdb.dll : fatal error LNK1120: 5 unresolved externals
1>Done building project "ccaosdb.vcxproj" -- FAILED.

mentioned in commit cfe207a7