wails dev: Unable to start application

[aiwaki]

Description

PS E:\app\src> wails dev       
DEB | Using go webview2loader
Wails CLI v2.3.1

Executing: go mod tidy        
  • Generating bindings: Done.
  • Installing frontend dependencies: Done.
  • Compiling frontend: Done. 

> frontend@1.0.0 dev
> vite

Port 5173 is in use, trying another one...
Port 5174 is in use, trying another one...

  VITE v3.2.5  ready in 777 ms

Vite Server URL: http://localhost:5175/
  ➜  Local:   http://localhost:5175/
  ➜  Network: use --host to expose
Running frontend DevWatcher command: 'npm run dev'
Building application for development...
  • Generating bindings: Done.
  • Generating application assets: Done.
  • Compiling application: Done.
 INFO  Wails is now using the 
new Go WebView2Loader. If you 
encounter any issues with it, 
please report them to https://
github.com/wailsapp/wails/issu
es/2004. You could also use th
e old legacy loader with `-tag
s native_webview2loader`, but 
keep in mind this will be deprecated in the near future.    

FATAL: Unable to start applica
tion: fork/exec E:\app\s
rc\cmd\build\bin\app-dev.exe:
 %1 is not a valid Win32 application.

To Reproduce

1. Run wails dev
2. Wait for the build
3. See the error:

FATAL: Unable to start applica
tion: fork/exec E:\app\s
rc\cmd\build\bin\app-dev.exe:
 %1 is not a valid Win32 application.

Expected behaviour

Normal behavior

Attempted Fixes

I'm completely confused. The application is automatically deleted from the build folder, but I can't determine at what exact moment this deletion occurs

System Details

wails doctor:

DEB | Using go webview2loader
Wails CLI v2.3.1

Scanning system - Please wait 
(this may take a long time)...Done.

# System

OS           | Windows 10 Pro 

Version      | 2009 (Build: 22000)
ID           | 21H2           

Go Version   | go1.18.3       

Platform     | windows        

Architecture | amd64          


# Wails

Version | v2.3.1

# Dependencies

Dependency | Package Name | Status    | Version
WebView2   | N/A          | Installed | 108.0.1462.54       
npm        | N/A          | Installed | 8.12.1
*upx       | N/A          | Installed | upx 3.96
*nsis      | N/A          | Available |
* - Optional Dependency       

# Diagnosis

Your system is ready for Wails development!
Optional package(s) installation details:
  - nsis : More info at https:
//wails.io/docs/guides/windows-installer/

Additional context

Sorry to bother you, but I really can't figure out what's wrong

[stffabi]

Thanks for using Wails and reporting this issue.

Never seen that error before, this seems like the build Go binary is not valid. Found one open issue on Golang golang/go#54564
FATAL: Unable to start application: fork/exec E:\app\src\cmd\build\bin\app-dev.exe: %1 is not a valid Win32 application.

A couple of question to hopefully narrow that down.

• Does this also happen with a newly initialzed wails init -n myproject project?
• Does it also occur when you try to start a production build created by wails build --debug?

[aiwaki]

* Does this also happen with a newly initialzed `wails init -n myproject` project?

No, it doesn't happen

* Does it also occur when you try to start a production build created by `wails build --debug`?

When I launch the application, I get the error message "This app can't run on your PC"

I recently upgraded to v2.3.1
I also slightly changed the structure of the project and wails.json, but it seems to me that it shouldn't cause this error

[stffabi]

Thanks for getting back with this information.

If it doesn't happen with a clean project, then it seems like some combination of options and your code in combination with Wails is somehow triggering this error. I've found the following issue on Golang golang/go#54564. But that seems a very limited case when this happens.

I recently upgraded to v2.3.1

Could you try downgrading to an older version to see if that solves the issue? What version did you use before?

[stffabi]

I'm very interested to find the root cause of this issue.

[aiwaki]

Could you try downgrading to an older version to see if that solves the issue? What version did you use before?

I used v2.2.0, installed it now, but it didn't solves the issue. Now I'm also very interested

[aiwaki]

I found out why this error is happening, but I need help solving it

If I add absolutely any thing from any package to main, then this error occurs:

package main

import (
	"embed"
	"app/cmd"
	"app/internal/utils"
)

//go:embed all:frontend/dist
var assets embed.FS

func main() {
        // Example
	utils.True() // "This app can't run on your PC"

	cmd.Run(&assets)
}

utils:

func True() bool {
	return true
}

The error occurs not only with functions, but also with anything else (variables, etc.)

It is noteworthy that when I build a project without wails, using go build, then everything is fine

[stffabi]

That's interesting. Did you use all needed build tags when building with 'go build'? Wails uses some special build tags. You could use 'wails build -v 2' to see a verbose log output with the used go build command.

Did you try to update go?

[aiwaki]

I just updated Go to the go1.19.4 windows/amd64 version and everything is fine now. I didn't understand anything, but okay. Thanks for the help!

[stffabi]

So that looks like a go compiler bug.
Maybe you could also test if the latest go 1.18 patch release does fix it too.

[stffabi]

Great you got it working.

As it seems to be a compiler bug, I think we could close this issue.