Even compilers need to run on a machine. To run the compiler itself, its code must also be compiled or interpreted. This creates a chicken-and-egg problem: How does the very first compiler run?
What is a Compiler?
A compiler translates source code written in a high-level language (like Go) into machine code — the binary instructions (101011...) that a CPU can execute directly. But the compiler itself is a program, so how is it created?
The Bootstrap Process
The First Compiler:
- The very first compilers were written in low-level languages like assembly or C. These languages don’t need a compiler to translate into machine code, as they work closely with the hardware.
Self-Hosting Compilers:
- Once a language is stable, its compiler can be rewritten in the same language. This is called a self-hosting compiler. For example, Go’s early compilers were written in C, but today, the Go compiler is written in Go itself.
Precompiled Binaries:
- When you install Go, you download a precompiled version of the Go compiler. This binary is already in machine code and ready to execute.
How Does This Work for Go?
Precompiled Go Compiler:
- The Go compiler you install is already compiled and doesn’t need further processing. It’s like receiving a fully built hammer to construct your own projects.
Compiling Your Code:
- When you write Go code and run
go build, the precompiled compiler translates your source code into a standalone binary that can run directly on your system.
- When you write Go code and run
The Chicken-and-Egg Problem Solved
The first Go compiler was written in C. Over time, Go became self-sufficient, and the compiler was rewritten in Go. Now, the Go team provides precompiled compilers, so you don’t need to worry about how the compiler itself was built. It’s already compiled and ready to use.