Hi all, Another update on the Clang MSVC ABI support front (which I’m trying to get to work in addition to MinGW + Clang)...
I’ve been making some good progress and was able to build Base as a DLL with this setup. The necessary build system changes are on the following branches (work in progress), which I will clean up and submit as PRs when this is working: https://github.com/gnustep/tools-make/tree/clang-msvc-support https://github.com/gnustep/libs-base/tree/clang-msvc-support However it seems that the generated gnustep-base.lib does not contain symbols for the ObjC classes. I’m getting linker errors for each ObjC class I am referencing in a test program: > lld-link: error: undefined symbol: $_OBJC_REF_CLASS_NSArray > >>> referenced by C:\Dev\tools-android\test.m:16 > >>> C:\msys64\tmp\test-aef6cd.o:(WinMain) > > lld-link: error: undefined symbol: __declspec(dllimport) > $_OBJC_CLASS_NSConstantString > >>> referenced by C:\msys64\tmp\test-aef6cd.o:(.objc_early_init) Is there some flag I need to pass to lld-link to ensure these are exported? I currently have -dll and -export-all-symbols. I also tried adding __declspec(dllexport) to the @interface declaration of these classes to no avail. Regarding the previous issue: > However, it fails checking for objc_sync_enter with the following linker > errors – any ideas what these could be about? I am guessing these somehow happen because referencing ObjC built-ins in a C file doesn’t work on Windows. I’m planning to skip these config checks when using this setup. Thanks, Frederik > Am 12.01.2021 um 21:47 schrieb Frederik Seiffert <frede...@algoriddim.com>: > > Hi all, > > As a second option I’ve been working on trying to build using the MSVC ABI > (i.e. without MinGW). > > Using the latest Clang 11 from the LLVM website and Pthreads-win32, plus > removing -lm from target.make, I was able to get quite a bit further running > Base configure. > > However, it fails checking for objc_sync_enter with the following linker > errors – any ideas what these could be about? > >> configure:8038: checking for objc_sync_enter >> configure:8038: /C/LLVM/bin/clang -o conftest.exe -g >> -I/c/GNUstep/MSVC/x64/include -I/c/GNUstep/MSVC/x64/include >> -I/c/GNUstep/MSVC/x64/include -I/c/GNUstep/MSVC/x64/include -x objective-c >> -fuse-ld=lld -L/c/GNUstep/MSVC/x64/lib -L/c/GNUstep/MSVC/x64/lib >> -L/c/GNUstep/MSVC/x64/lib -L/c/GNUstep/MSVC/x64/lib conftest.c -lpthread >> -fuse-ld=lld -pthread -fexceptions -fobjc-runtime=gnustep-2.0 -fblocks >> -L/home/Frederik -LSeiffert/GNUstep/Library/Libraries >> -L/c/GNUstep/MSVC/x64/lib -lobjc >&5 >> conftest.c:119:6: warning: incompatible redeclaration of library function >> 'objc_sync_enter' [-Wincompatible-library-redeclaration] >> char objc_sync_enter (); >> ^ >> conftest.c:119:6: note: 'objc_sync_enter' is a builtin with type 'int (id)' >> 1 warning generated. >> lld-link: error: relocation against symbol in discarded section: >> __start_.objcrt$SEL >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __stop.objcrt$SEL >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __start_.objcrt$CLS >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __stop.objcrt$CLS >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __start_.objcrt$CLR >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __stop.objcrt$CLR >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __start_.objcrt$CAT >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __stop.objcrt$CAT >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __start_.objcrt$PCL >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __stop.objcrt$PCL >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __start_.objcrt$PCR >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __stop.objcrt$PCR >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __start_.objcrt$CAL >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __stop.objcrt$CAL >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __start_.objcrt$STR >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> >> lld-link: error: relocation against symbol in discarded section: >> __stop.objcrt$STR >>>>> referenced by C:\tmp\conftest-78a937.o:(.objc_init) >> PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash >> backtrace. >> 0. Program arguments: C:\LLVM\bin\lld-link -out:conftest.exe >> -defaultlib:libcmt -libpath:C:\Program Files (x86)\Microsoft Visual >> Studio\2019\Professional\VC\Tools\MSVC\14.28.29333\lib\x64 >> -libpath:C:\Program Files (x86)\Microsoft Visual >> Studio\2019\Professional\VC\Tools\MSVC\14.28.29333\atlmfc\lib\x64 >> -libpath:C:\Program Files (x86)\Windows Kits\10\Lib\10.0.18362.0\ucrt\x64 >> -libpath:C:\Program Files (x86)\Windows Kits\10\Lib\10.0.18362.0\um\x64 >> -libpath:C:\LLVM\lib\clang\11.0.0\lib\windows >> -libpath:C:/GNUstep/MSVC/x64/lib -libpath:C:/GNUstep/MSVC/x64/lib >> -libpath:C:/GNUstep/MSVC/x64/lib -libpath:C:/GNUstep/MSVC/x64/lib >> -libpath:C:/msys64/home/Frederik -libpath:Seiffert/GNUstep/Library/Libraries >> -libpath:C:/GNUstep/MSVC/x64/lib -nologo -debug C:\tmp\conftest-76158a.o >> pthread.lib objc.lib > > >> configure:8038: result: no >> configure:8052: error: The objc runtime library does not appear to have >> synchronisation support. Try re-configuring gnustep-make with a CPPFLAGS >> variable containing a -L point to specify the directory containing the >> correct libobjc, or using the --with-objc-lib-flag=... option. > > > Thanks, > Frederik > >
