GCC

GCC (GNU Compiler Collection) is a compiler (with front, optimiser, and back-end) primarily for C. Its sister project, G++, compiles primarily for C++. Both compilers target an extremely wide range of architectures, including popular (x86, ARM, RISC-V), less popular (PowerPC, Alpha, MIPS), and esoteric or embedded processors.

Flags

Both compilers share common flags to modify compilation behaviour.

• No flags — compiles to an executable called a.out (on Linux) or a.exe (on Windows).
• • -o <NAME> — specifies the output executable file name.
• Compiler phases
  • -E — stops the compiler at the preprocessor stage.
  • -S — stops the compiler after assembly generation but before the assembler.
  • -C — compiles without using the linker.
  • -save-temps — outputs all intermediate files (preprocessor, assembly, executable).
• Debug behaviour
  • -Wall — enables compiler warnings.
  • -g — compiles in debug mode.
• Language-specific
  • -std=<VERSION> — compiles with a specific language version.
    • For example, to compile with C++17, we can do -std=c++17.