This is the GNU Go compiler for the build architecture, which compiles Go on platforms supported by the gcc compiler. It uses the gcc backend to generate optimized code.

PETSc is the "Portable Extensible Toolkit for Scientific Computation", a suite of data structures and routines for the scalable (parallel) solution of scientific applications modeled by partial differential equations. It employs the MPI standard for all message-passing communication. Several sample scientific applications, as well as various papers and talks, demonstrate the features of the PETSc libraries.

This is the GNU C compiler, a fairly portable optimizing compiler for C.

pgpool-II is a middleware that works between PostgreSQL servers and a PostgreSQL database client. This package contains the pgpool control protocol library (libpcp).

This is the GNU C++ compiler, a fairly portable optimizing compiler for C++.

This is the GNU C compiler for the x86_64-linux-gnu architecture, a fairly portable optimizing compiler for C.