Failed to load dll. Specified module could not be found - windows

Question

I have some code that I wrote in golang (on ubuntu) and tried to package as a windows exe but unfortunately, due to some cgo dependencies from a github project, I ended up having to build my package as a dll as per this answer https://stackoverflow.com/a/49079049/4750381 because it would not compile as a runnable exe file for windows (even using MinGw).
My compile line was:
GOOS=windows GOARCH=386 CGO_ENABLED=1 CC=i686-w64-mingw32-gcc go build -buildmode=c-shared -o main.dll main.go
My main package code looks like this:
package main
import (
"C"
"fmt"
console "github.com/AsynkronIT/goconsole"
"github.com/AsynkronIT/protoactor-go/actor"
"path/to/repo"
)
const cfgPath string = "./config.json"
func main() {
fmt.Println("from main")
}
func dllRun() {
// Used for running the test and various other operations, thus generally all lines except 1 will be commented out
ctx := actor.EmptyRootContext
props := actor.PropsFromProducer(testmachine.NewTestMachine(cfgPath))
pid, err := ctx.SpawnNamed(props, "tm")
if err != nil {
panic(err)
}
defer func() { // run after the read line fucntion executes and terminates the program
ctx.Poison(pid)
}()
console.ReadLine()
}
I wrote another go script (using windows this time) to try to load and read that DLL file:
import (
"syscall"
)
func main() {
myDLL := syscall.NewLazyDLL("C:/Users/konyenso/Documents/DLLOpener/main.dll")
mainCall := myDLL.NewProc("dllRun")
ret, _, err := mainCall.Call()
if err != nil {
panic(err) // calling myDLL.mainCall failed
}
if ret == 0 {
print("Could not set the desired attributes")
// TODO: call GetLastError to get more information
}
print("OK")
}
But now I always get the error below even though my file path is ok:
panic: Failed to load C:/Users/konyenso/Documents/DLLOpener/main.dll: The specified module could not be found.
goroutine 1 [running]:
syscall.(*LazyProc).mustFind(0x13019400)
c:/go/src/syscall/dll_windows.go:311 +0x42
syscall.(*LazyProc).Call(0x13019400, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x4623e0)
c:/go/src/syscall/dll_windows.go:327 +0x21
main.main()
C:/Users/konyenso/Documents/DLLOpener/main.go:11 +0xa5
Please could someone tell me what I'm doing wrong? I've been tweaking this all day with little success. Ideally I would want to build an exe straight from ubuntu without the dll but if that's not feasible, I would at least like to be able to run my dll from another exe file.
Thanks for any assistance.
********** EDIT****************************
So I wrote some C++ code to try to open the dll file (made 64 and 32 bit versions of both)
#define UNICODE
#include <windows.h>
#include <iostream>
/* Define a function pointer for our imported
* function.
* This reads as "introduce the new type f_funci as the type:
* pointer to a function returning an int and
* taking no arguments.
*
* Make sure to use matching calling convention (__cdecl, __stdcall, ...)
* with the exported function. __stdcall is the convention used by the WinAPI
*/
typedef int (__stdcall *f_funci)();
int main()
{
HINSTANCE hGetProcIDDLL = LoadLibrary((LPCWSTR)"C:\\Users\\konyenso\\Documents\\DLLOpener\\main.dll");
if (!hGetProcIDDLL) {
std::cout << "could not load the dynamic library" << std::endl;
return EXIT_FAILURE;
}
// resolve function address here
f_funci funci = (f_funci)GetProcAddress(hGetProcIDDLL, "dllRun");
if (!funci) {
std::cout << "could not locate the function" << std::endl;
return EXIT_FAILURE;
}
std::cout << "funci() returned " << funci() << std::endl;
return EXIT_SUCCESS;
}
Same issue:
Screenshot showing could not load
As you can see from this below screenshot, the file path matches so I have no idea what's going on.
Screenshot showing paths confirmed

Answer 1

First,you need export dll method like this:
// export dllRun
func dllRun() {
There is a simple example,
https://github.com/whtiehack/checkdll_log
Second,
Go main program could not load Go dll correct because
https://github.com/golang/go/issues/34168
https://github.com/golang/go/issues/22192
In summary, in Windows, there can not have more than two go runtimes in a main program.