SDL2_image fails loading libpng on latest versions when cross-compiling

I’m building an SDL application in Go using a sample repository to reproduce the problem. (full repro instructions here)

So I’m trying to build from Windows Subsystem for Linux to create a Windows build (using the bash script in the example). It works for SDL2_image version 2.0.1 but not newer versions. On newer versions, it fails with the following message:

Failed to load PNG: Failed loading libpng16-16.dll: The specified procedure could not be found.

I’m not sure how to debug from here, but the only thing I change to go from failure to working is changing the SDL2_image version. Any help would be appreciated!

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You’ll need to download that DLL, and place it in the same directory as your executable to get it to work. Are you running that from a Windows machine and getting that error, or when you’re compiling?

The png library is being included, and lives in the same directory. This is an image from one of the links:

As you can see, libpng is in the folder.

And again, the only thing that changed was the SDL_image version to go from broken (on 2.0.2 and 2.0.3) to working (on 2.0.1).

And to clarify, this is a runtime error. Compilation succeeds without error.

Is that the 32-bit version of libpng or the 64-bit? Does it match which one you’re compiling with?

Also, where does that error occur? When the program attempts to load, or is it the error message that SDL_Image is returning?

I’m honestly not sure how to check what version of libpng it is, but it is the libpng bundled at - I’m not building it myself or including it from somewhere else.

The fatal error occurs when attempting to load a png image using SDL2_image. The line printing the error message is here, immediately after a call to img.Load, which I believe corresponds to IMG_Load() declared in SDL_image.h.

If I’m not mistaken, that link is for the 64 bit version of libpng. Are you compiling for 32 or 64 bit?
libPNG 32bit might be what you need.

I am compiling for 64 bit, which seems to be the default for my machine. I’m making it explicit in my build file now to codify it (GOARCH=amd64).

I have discovered that the crash doesn’t happen if I build using version 2.0.3 and replace the libpng with the libpng provided in 2.0.1. Therefore I have decided to submit a bug.

Sorry I couldn’t have been better help.

I love you dude! The issue continue to v2.0.5… Thanks a lot