SectorC is a C compiler written in x86-16 assembly that can fit within the 512-byte boot sector of an x86 machine. Despite the size limitations, a large subset of C is supported, including global variables, functions, if and while statements, operators, pointer dereference, inline machine-code, and comments. A tokenizer/lexer was developed that also converts numbers from string to integer, and it is minimalist and straightforward. Two big insights revealed and utilized were that atoi() is a hash function and atoi() tokens can be used to generate code. Barely C Programming Language was created, which is technically still C and turing-complete. The runtime features a collection of library routines coded in inline asm, and there is no error-handling.
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