VPI on Windows

[gatk555]

I am mainly here to thank developers for this nifty repository. Lacking a Windows machine, I am using Actions to check that my code can work there and expected to have to build my own GHDL. This Action has saved much time.

I have run into a problem, for which likely perhaps a documentary fix is possible. Background: I build with "ghdl -e -shared", adding my own code with "-Wl,ghdl_shim.o". No problem there, but I also have a VPI module built with:

"shell ghdl --vpi-link clang ghdl_vpi.o -o ghdlng.vpi -lm -L. -l$base"

That is also apparently fine, DUMPBIN.EXE says it is a good DLL, although MSYS's ldd chokes on it. (The last part is because this VPI code calls back into the main DLL.) But when trying to run:

loading VPI module './ghdlng.vpi'
The specified module could not be found.

555:error: cannot load VPI module './ghdlng.vpi

A fix is straightforward: "copy D:\a_temp\msys64\UCRT64\lib\libghdlvpi.dll ." So the problem is a combination of lousy error reporting by the OS (GHDL seems to do the right thing), and the library is not in the DLL search path. Being a baby at Windows admin, I have no idea how to add it, but if that is not easy it may be worth documenting this trap. Thanks!

[tgingold]

On Windows, DLL are sheared in the PATH environment variable.
You can simply move libghdlvpi.dll in the same directory as ghdl.exe

Or you can modify PATH, but I don't know which shell are you using.

[gatk555]

Thanks. I had already adopted your second solution, copying the DLL, but it seems a poor way to do it, with versioning problems likely in the future.

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On Mon, 9 Dec 2024 at 06:36, tgingold ***@***.***> wrote: On Windows, DLL are sheared in the PATH environment variable. You can simply move libghdlvpi.dll in the same directory as ghdl.exe Or you can modify PATH, but I don't know which shell are you using. — Reply to this email directly, view it on GitHub <#42 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/APAYEBEJCRDUA4RE5V4XG6T2EU267AVCNFSM6AAAAABTG5UQXGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDKMRXGA2TSOJXGE> . You are receiving this because you authored the thread.Message ID: ***@***.***>