I'm trying to figure how to use IMPLIB with D DLLs.

The DLL example from the samples folder in DMD:

dll.d > http://pastebin.com/C9NJtqUV
mydll.d > http://pastebin.com/8idbnge0
test.d > http://pastebin.com/6c953BSJ
mydll.def > http://pastebin.com/4enbfbc7

First I'll show how to build without using IMPLIB (since I have the sources). I use a build command to create the header (interface) files & the import library, all in one go:

$ dmd -L/IMPLIB -H -ofmydll.dll mydll.d dll.d mydll.def

The dll is cooked, I have an import library (mydll.lib) and the interface files. Ok, now I link the library with my driver (test.d):

dmd test.d mydll.lib

$ test.exe
> hello dll world

Everything works ok.

But, let's say I didn't have the d source files, and all I had was the .dll file, the .def file, and the interface files. I have to create the import lib with IMPLIB. I run the command:

$ implib mydll2.lib mydll.def

Then I try to link mydll2.lib with the driver:

$ dmd test.d mydll2.lib
> Error 42: Symbol Undefined _D5mydll8dllprintFZv
--- errorlevel 1

The .lib file seems to be completely empty when I use IMPLIB this way. If instead of using the .def file I use the .lib file directly, like so:

$ implib mydll3.lib mydll.dll

then I get back a .lib file with some actual symbols (its 2KB compared to the first .lib file, which is 1KB), but I still can't link it:

$ dmd test.d mydll3.lib
 Error 42: Symbol Undefined _D5mydll8dllprintFZv
--- errorlevel 1

It seems to be that IMPLIB creates the lib files without underscores before the symbol names.

To recap:
The first mydll.lib which was created by DMD uses underscores before symbols,
the second lib file created by IMPLIB and a .DEF file has no symbols in it,
and the third lib file created by IMPLIB and mydll.dll exports symbols without underscores.

So, am I missing an important step in building an import library with IMPLIB?

One other thing. I'm trying to use a tool called objconv, it allows modification of .lib files, e.g. adding aliases to existing symbols. I was trying to add aliases to existing symbols and make them have underscores, but the tool complains that I can't use OMF file formats that have a 16bit word size (It can only export to 32bit+ word size, but it can read lower ones).

I'm not sure if the tool is broken or if D's .lib files really have a 16bit word size..? That wouldn't make much sense, I'm not running DOS. :)

The tool can be found here: http://www.agner.org/optimize/#objconv
It was already posted on D NG: http://www.digitalmars.com/d/archives/digitalmars/D/announce/objconv_2.03_released_includes_.OBJ_disassembler_14246.html

Andrej Mitrovic Wrote:

> I'm trying to figure how to use IMPLIB with D DLLs.

Forgive me for my ignorance, I neglected to use the /s switch for IMPLIB:

$ implib /s mydll3.lib mydll.dll
$ dmd test.d mydll3.lib
$ test
hello dll world

However I still get a .lib file with no symbols if I use IMPLIB with a .def file instead of a .dll file. Is this a bug?

Andrej Mitrovic Wrote:

> I'm trying to figure how to use IMPLIB with D DLLs.

Andrej Mitrovic wrote:
> One other thing. I'm trying to use a tool called objconv, it allows modification of .lib files, e.g. adding aliases to existing symbols. I was trying to add aliases to existing symbols and make them have underscores, but the tool complains that I can't use OMF file formats that have a 16bit word size (It can only export to 32bit+ word size, but it can read lower ones).
> 
> I'm not sure if the tool is broken or if D's .lib files really have a 16bit word size..? That wouldn't make much sense, I'm not running DOS. :)
> 
> The tool can be found here: http://www.agner.org/optimize/#objconv
> It was already posted on D NG: http://www.digitalmars.com/d/archives/digitalmars/D/announce/objconv_2.03_released_includes_.OBJ_disassembler_14246.html

It's support for D's .obj/.lib files is very limited. The modifications I made to it were enough to let it do asm dumps (which is what I wanted it for), but not enough to perform obj file format conversions.