Cross-compiling from WSL and Linux causes missing entry point DeleteCriticalSection - linux

Question

I'm trying to cross-compile from WSL and Linux to Win32 using i686-w64-mingw32-gcc. The program is dependent on some DLL:s that I have downloaded, and are known to work when used for an exe cross-compiled on Cygwin. Compilation and linking works without throwing any errors or warnings, but when I run the resulting executable on Windows (by double-clicking on it in an Explorer window) I get a Windows-error-prompt:
The procedure entry point DeleteCriticalSection could not be located in the DLL...
and then it points to the program (the .exe) itself, not a DLL (message translated from Swedish ;-).
When I do the exact same thing on Cygwin with the same archive for the DLL:s and the same DLL:s the resulting exe works as it should.
The new(ish) Dependencies shows some red lines for COMCTL32 and OLEAUT32, but those are the same for both.
A very simple windows GUI app compiles and runs, so it's not the cross-compile as such that is causing the issue. The DLL:s in combination with WSL/Ubuntu/GNU cross-compilation seems to be the culprit.
Instructions
EDIT: after explicitly following my own instructions and explicitly re-installing the cross-compilation tool-chain the instructions below no longer creates a faulty exe. But the original problem remains.
I'm happy to take any ideas on what to try next.
Here are instructions to repeat what I have. Create an empty directory in WSL and run
$ sudo apt install binutils-mingw-w64-i686 gcc-mingw-w64-i686
$ wget https://github.com/DavidKinder/Windows-Glk/releases/download/1.50/WindowsGlk-150.zip
$ unzip WindowsGlk-150.zip
Then create startup.c with the following content
#include <unistd.h>
#include "glk.h"
#include "WinGlk.h"
int winglk_startup_code(const char* cmdline)
{
return 1;
}
void glk_main(void) {
sleep(10);
}
(Fix the capitalized include of "glk.h" in Glk.c or you'll get an error.)
Compile and link with
$ i686-w64-mingw32-gcc -mwindows -I Include/ Glk.c startup.c Glk.lib
to get an a.exe. The message only shows up in Gui-mode so you need to run it from an explorer window:
explorer.exe .
and double-click on a.exe.
WSL and Linux vs. Cygwin
I've done the same cross-compilation on a "real" Ubuntu 20.04 and getting the same problem. Again, doing the exact same steps in Cygwin produces a runable exe. This points to a cross-compilation problem with some facet of
what the exe and the DLL:s are doing. (There is no code in the exe that does anything with critical sections. Could this be an API mismatch?)
Since the DLL:s are the same it is reasonable to suspect the actual cross-compilation of sources in my program.
Is there anything in the cross-compilation toolchain on Linux that might differ? Which Windows run-times and API-versions are targeted?
I'm happy to take any ideas on what to try next.