C++ cross compiling on Ubuntu for Windows linking LIBEAY DLL's 32 and 64 bit

Cross-compiling C++ code on Ubuntu for Windows involves several steps, including setting up a cross-compilation environment and handling libraries correctly. If you need to link against both 32-bit and 64-bit DLLs (like LIBEAY32.DLL and LIBEAY64.DLL), you'll need to follow these general steps:

1. Install MinGW-w64:
   MinGW-w64 is a toolchain for cross-compiling Windows applications on Linux. Install it using the package manager:

   bashCopy code
   sudo apt-get install mingw-w64
   
   

2. Set Up Environment Variables:
   Configure environment variables to use the cross-compiler and specify the architecture. For example, for 64-bit:

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   export CC=x86_64-w64-mingw32-gcc
   
   export CXX=x86_64-w64-mingw32-g++
   
   

   For 32-bit:

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   export CC=i686-w64-mingw32-gcc
   
   export CXX=i686-w64-mingw32-g++
   
   

3. Cross-Compile:
   Compile your C++ code using the specified cross-compiler. For example:

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   $CC -o myapp.exe myapp.cpp -L/path/to/dlls -lmylib
   
   

4. Copy DLLs:
   Copy the required DLLs (like LIBEAY32.DLL or LIBEAY64.DLL) to the directory where your compiled executable is located. Make sure you have both 32-bit and 64-bit versions of the DLLs.

5. Run on Windows:
   Transfer the compiled executable and DLLs to a Windows system and run the executable. Make sure the DLLs are in the same directory as the executable or in a directory listed in the PATH environment variable.

Keep in mind that cross-compilation can be complex and might require adjustments depending on your specific project. Also, ensure that the DLLs are compatible with your cross-compiled executable (32-bit or 64-bit). Check if the libraries you're linking against are available in the correct format for cross-compilation.

As of my knowledge cutoff in September 2021, these steps should help you cross-compile and link against 32-bit and 64-bit DLLs when targeting Windows from Ubuntu. If you encounter any issues or need more up-to-date information, refer to the MinGW-w64 documentation or relevant community resources.