DLL creation fails with undefined symbol error

Fri Apr 26 14:20:24 UTC 2019

On Friday, 26 April 2019 at 12:37:46 UTC, evilrat wrote:
> On Friday, 26 April 2019 at 05:08:32 UTC, dokutoku wrote:
>> I tried to build a DLL in a Windows 64bit environment.
>> It works well if the compiler is DMD, but in the case of LDC, 
>> the build fails with a large number of undefined symbol errors.
>>
>> Is this a DUB or LDC bug?
>> Or do I have to specify some additional arguments to the 
>> command?
>
> Seems like DMD links some system and/or runtime libs for you, 
> while LDC doesn't.
>
> What symbols are missing? It could be just msvcrt and some of 
> the default system libs such as system32 and the like.

There was an error like this.

```
Performing "debug" build using C:\ldc\bin\ldc2.exe for x86_64.
test ~master: building configuration "library"...
lld-link: error: <root : undefined symbol: _DllMainCRTStartup
lld-link: error: undefined symbol: strlen
     referenced by druntime-ldc.lib(exception.obj):(_d_assertp)
     referenced by druntime-ldc.lib(exception.obj):(_d_unittestp)
     referenced by 
druntime-ldc.lib(exception.obj):(_d_arrayboundsp)

lld-link: error: undefined symbol: __acrt_iob_func
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)

lld-link: error: undefined symbol: __stdio_common_vfwprintf
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)

lld-link: error: undefined symbol: __stdio_common_vfwscanf
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)

lld-link: error: undefined symbol: __stdio_common_vswprintf
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN5)

lld-link: error: undefined symbol: __stdio_common_vswscanf
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)

lld-link: error: undefined symbol: __stdio_common_vfprintf
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)

lld-link: error: undefined symbol: __stdio_common_vfscanf
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)

lld-link: error: undefined symbol: __stdio_common_vsprintf
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN5)
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN5)

lld-link: error: undefined symbol: __stdio_common_vsscanf
     referenced by 
legacy_stdio_definitions.lib(legacy_stdio_definitions.obj):($LN3)

lld-link: error: undefined symbol: strlen
     referenced by 
druntime-ldc.lib(object.obj):(_D6object10ModuleInfo4nameMxFNaNbNdNiZAya)

lld-link: error: undefined symbol: malloc
     referenced by druntime-ldc.lib(lifetime.obj):(_d_newclass)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_D2rt8lifetime__T11_d_newclassVbi1ZQsFNbxC14TypeInfo_ClassZC6Object)
     referenced by druntime-ldc.lib(lifetime.obj):(_d_allocclass)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_D2rt8lifetime__T11_d_newclassVbi0ZQsFNbxC14TypeInfo_ClassZC6Object)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_D2rt8lifetime10__blkcacheFNbNdZPS4core6memory8BlkInfo_)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_D2rt8lifetime12__getBlkInfoFNbPvZPS4core6memory8BlkInfo_)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_D2rt8lifetime20__insertBlkInfoCacheFNbS4core6memory8BlkInfo_PQxZv)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arrayshrinkfit)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arrayshrinkfit)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetcapacity)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetcapacity)
     referenced by druntime-ldc.lib(lifetime.obj):(_d_delarray_t)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetlengthT)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetlengthT)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetlengthT)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetlengthT)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetlengthT)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetlengthT)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetlengthiT)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetlengthiT)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetlengthiT)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetlengthiT)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetlengthiT)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arraysetlengthiT)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arrayappendcTX)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arrayappendcTX)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arrayappendcTX)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arrayappendcTX)
     referenced by 
druntime-ldc.lib(lifetime.obj):(_d_arrayappendcTX)

lld-link: error: undefined symbol: free
     referenced by 
druntime-ldc.lib(lifetime.obj):(_D2rt8lifetime19_staticDtor_L532_C1FZv)

lld-link: error: undefined symbol: fwrite
     referenced by druntime-ldc.lib(eh_msvc.obj):(fatalerror)

lld-link: error: undefined symbol: fputc
     referenced by druntime-ldc.lib(eh_msvc.obj):(fatalerror)

lld-link: error: undefined symbol: abort
     referenced by druntime-ldc.lib(eh_msvc.obj):(fatalerror)

lld-link: error: undefined symbol: set_terminate
     referenced by 
druntime-ldc.lib(eh_msvc.obj):(_d_throw_exception)

lld-link: error: undefined symbol: free
     referenced by 
druntime-ldc.lib(eh_msvc.obj):(_d_throw_exception)
     referenced by 
druntime-ldc.lib(eh_msvc.obj):(_D3ldc7eh_msvc14ExceptionStack4pushMFNbC6object9ThrowableZv)
     referenced by 
druntime-ldc.lib(eh_msvc.obj):(_D3ldc7eh_msvc14ExceptionStack6__dtorMFNbZv)
     referenced by 
druntime-ldc.lib(eh_msvc.obj):(_D3ldc7eh_msvc14ExceptionStack4growMFNbZv)
     referenced by 
druntime-ldc.lib(eh_msvc.obj):(_D3ldc7eh_msvc14ExceptionStack8opAssignMFNbNcNjSQBuQBtQBoZQl)
     referenced by 
druntime-ldc.lib(eh_msvc.obj):(_D3ldc7eh_msvc12FiberContext11__fieldDtorMFNbZv)
     referenced by 
druntime-ldc.lib(eh_msvc.obj):(_D3ldc7eh_msvc12FiberContext8opAssignMFNbNcNjSQBsQBrQBmZQl)
     referenced by 
druntime-ldc.lib(eh_msvc.obj):(_d_eh_swapContext)
     referenced by 
druntime-ldc.lib(eh_msvc.obj):(_D3ldc7eh_msvc19_staticDtor_L552_C1FZv)

lld-link: error: undefined symbol: malloc
     referenced by 
druntime-ldc.lib(threadaux.obj):(_D4core3sys7windows9threadaux10thread_aux18enumProcessThreadsFkPFkPvZbQeZb)
     referenced by 
druntime-ldc.lib(threadaux.obj):(_D4core3sys7windows9threadaux10thread_aux18enumProcessThreadsFkPFkPvZbQeZb)

lld-link: error: too many errors emitted, stopping now (use 
/errorlimit:0 to see all errors)

Error: linking with LLD failed
C:\ldc\bin\ldc2.exe failed with exit code 1.
```