gcc@15 for Mac

GCC is the GNU Compiler Collection and one of the Free Software Foundation's most central projects. It translates source code in multiple languages such as C, C++, Fortran, and Ada into programs that machines can execute, making it a fundamental tool for developers building software from the command line. For most Linux users, the compiler preinstalled on the system is often GCC; it is also indispensable when compiling kernel modules, building open-source projects, or studying compiler principles. gcc@15 refers to the 15th major version series within this compiler collection, suited to developers who need support for newer language standards or who want to track upstream progress. It offers no graphical interface and is invoked entirely through commands, making it a typical command-line tool.