Go Programming: Basic Makefile

Here’s a basic Makefile you can use to compile your main.go file:

# Makefile for compiling main.go

# Compiler settings
GO = go
GOFLAGS = -v

# Targets
TARGET = main

# Build rules
.PHONY: all clean

all: $(TARGET)

$(TARGET): *.go
 $(GO) build $(GOFLAGS) -o $@ $^

clean:
 rm -f $(TARGET)

This Makefile uses $(GO) build to compile all the Go source files (*.go) in the directory into the $(TARGET) executable file.

Let’s break it down:

• The # symbol at the beginning of a line indicates a comment.
• The GO variable is set to the name of the Go compiler (go).
• The GOFLAGS variable is set to the compiler flags we want to use when building the executable.
• The TARGET variable is set to the name of the executable we want to create (main).
• The .PHONY target tells Make that all and clean are not real files, but just phony targets that don't need to be built.
• The all target is the default target that will be built when you run make. It depends on the $(TARGET) target.
• The $(TARGET) target depends on all the Go source files (*.go) and will be built by compiling them together using the Go compiler.
• The $^ variable expands to all the dependencies of the target (*.go in this case).
• The clean target removes the executable file.

Here’s a more detailed explanation of how the $(TARGET) target works:

$(TARGET): *.go
 $(GO) build $(GOFLAGS) -o $@ $^

This rule says that the $(TARGET) target depends on all the Go source files (*.go), and that it should be built by running the $(GO) build command with the specified flags. Here's what each part of the command does:

• $(GO) expands to the name of the Go compiler (go).
• build is the name of the Go command that compiles and links Go source code to create an executable.
• $(GOFLAGS) expands to the compiler flags we want to use (-v in this case, which tells the compiler to be verbose).
• -o $@ specifies the name of the output file ($@ expands to the name of the target, which is $(TARGET) or main in this case).
• $^ expands to all the dependencies of the target (*.go in this case), which tells the compiler to compile all the Go source files into the executable.

I hope this explanation helps!