Building Systems

🔍 What Do configure, make, and make install Do?

📌 1️⃣ ./configure - Prepares the Build

What It Does:

• Checks your system to see if it has the necessary dependencies (like gcc, make, etc.).

• Sets up configuration files (e.g., Makefile) based on your system.

• Defines where the program will be installed (via -prefix=<install_path>).

Example:

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./configure --prefix=/opt/glibc-2.32

• This tells the software:"When installed, put the files in /opt/glibc-2.32 instead of the default /usr/local."

• If you don’t use -prefix, the default install location is /usr/local.

What It Produces:

• Creates a Makefile that tells make how to build the program.

📌 2️⃣ make - Compiles the Source Code

What It Does:

• Reads the Makefile (created by configure).

• Compiles the source code into object files (.o files).

• Links the compiled files to create an executable binary.

Example:

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make -j$(nproc)

• The j$(nproc) flag tells make to use all available CPU cores for faster compilation.

What It Produces:

• A compiled version of the program (in the build/ folder, not installed yet).

Note: At this stage, the program is compiled but not installed. You can run it from the build directory but not from anywhere else.

📌 3️⃣ make install - Installs the Compiled Program

What It Does:

• Copies the compiled files from the build/ folder to the directory specified by -prefix.

• Makes the program available system-wide (or in the Conda environment, if installed there).

Example:

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make install

• If you used -prefix=/opt/glibc-2.32, then after make install, the files will be installed in:

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/opt/glibc-2.32/bin/
/opt/glibc-2.32/lib/

• bin/ → Executables

• lib/ → Libraries

• include/ → Headers

• share/ → Data files

• etc/ → Config files

• lib/pkgconfig/ → Metadata

What It Produces:

• The final installed version of the program.

• Now, you can run it from anywhere without specifying a full path.

🚀 TL;DR: What Each Step Does