Cross compile Static Library from Linux for windows

Introduction

When developing software, there is a high chance that software might be used in various operating systems. Therefore, it is important to build software in a cross-platform manner to ensure compatibility with multiple operating systems. In this article, we will focus on cross-compiling static libraries from Linux for Windows.

What is a Static Library?

A static library is a file that contains pre-compiled code that can be linked with an executable program to create a single, self-contained executable. code in a static library is linked directly into executable, which makes it faster and more efficient than dynamic libraries.

What is Cross-Compiling?

Cross-compiling is process of building software on one platform that is intended to run on a different platform. For example, building a Windows application on a Linux machine.

Why Cross-Compile?

Cross-compiling has several benefits, such as −

• Increased productivity − cross-compiling saves time, allowing developers to build for multiple platforms without having to switch between different machines.

• Improved portability − cross-compiling ensures that software is compatible with multiple platforms.

• Reduced development costs − cross-compiling eliminates need for multiple machines and operating systems, reducing hardware and software costs.

• Easier testing − cross-compiling enables developers to test their software on multiple platforms, without need for physical hardware.

Cross Compiling Static Libraries from Linux for Windows

Cross-compiling static libraries from Linux for Windows is a fairly simple process. Here are steps −

• Step 1 − Install Required Cross-Compiler

The first step is to install cross-compiler that will allow us to compile our code for Windows on a Linux machine. There are several cross-compilers available for Linux, such as MinGW, Cygwin, and Mingw-w64.

For this article, we will use Mingw-w64 cross-compiler. To install Mingw-w64 cross-compiler on Ubuntu, run following command −

sudo apt-get install mingw-w64

• Step 2 − Create Source Code

The next step is to create source code for static library. In this example, we will create a simple "hello world" static library.

Create a file called "hello.c" and add following code −

#include <stdio.h>

void hello() {
   printf("Hello, world!
");
}

• Step 3 − Compile Static Library

The next step is to compile static library using cross-compiler. Run following command −

x86_64-w64-mingw32-gcc -c hello.c -o hello.o

This command will compile "hello.c" source code into an object file called "hello.o".

• Step 4 − Create Static Library

The next step is to create static library from object file. Run following command −

x86_64-w64-mingw32-ar rcs libhello.a hello.o

This command will create static library file "libhello.a" from object file "hello.o".

• Step 5 − Test Static Library

The final step is to test static library by creating a simple Windows application that uses static library.

Create a file called "main.c" and add following code −

#include <windows.h>
extern void hello();
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) {
   hello();
   return 0;
}

• Step 6 − Compile Windows Application

The final step is to compile Windows application using cross-compiler. Run following command −

x86_64-w64-mingw32-gcc main.c --o main.exe -L. -lhello -mwindows

This command will compile "main.c" source code into a Windows executable called "main.exe". "-L." option tells compiler to look for static library in current directory, and "-lhello" option tells compiler to link with "libhello.a" static library.

Cross-compiling static libraries from Linux for Windows can be a useful skill to have as a developer. It can help you to create software that is compatible with multiple platforms, increase your productivity, and save you time and money in long run.

In addition to steps outlined above, there are a few things to keep in mind when cross-compiling static libraries from Linux for Windows −

• Platform-specific code − When cross-compiling, it's important to keep in mind that code may be running on a different platform. Therefore, it's important to avoid using platform-specific code in your static libraries.

• Testing − Testing is a crucial step in software development process, and cross-compiling is no exception. It's important to test your static libraries on multiple platforms to ensure they work as intended.

• Documentation − When cross-compiling, it's important to document process so that other developers can easily follow along. This can include documenting cross-compiler used, commands used to compile static library, and any platform-specific considerations.

Overall, cross-compiling static libraries from Linux for Windows is a valuable skill for developers to have. By following steps outlined in this article and keeping above considerations in mind, you can create high-quality software that is compatible with multiple platforms.

Conclusion

Cross-compiling static libraries from Linux for Windows is a straightforward process. With Mingw-w64 cross-compiler, developers can easily build static libraries that are compatible with Windows. Cross-compiling saves time and reduces development costs, allowing developers to focus on building great software that is compatible with multiple platforms.