Deep Blue C

The Deep Blue C (DBC) is one of the few C compilers for the Atari 8 bit. John H. Palevich is the author of this compiler. The syntax supported by DBC is close to the ANSI C with significant limitations.

Limitations

The following language constructs are not supported:

• structs
• unions
• multidimensional arrays
• floating point numbers
• sizeof operator
• type casting
• functions return integer only results

Other non-standard properties of Deep Blue C:

• The last part of "switch" clause must be ended with: "break", "continue" or "return".
• char is unsigned.
• The maximum length of source code line has to be less than 80 characters.
• The number of arguments for functions cannot exceed 126.
• $( and $) are used instead of { and }.

Sample program

The exemplary program writes the "Hello World!" message on the user screen.

 main()
 $(
   printf("Hello World!");
 $)

Performance

The DBC compiler does not create the native executable for 6502 processor but intermediate code called C-code. The C-code is then executed by C-code interpreter. According to Atari 8-bit FAQ the DBC creates binary code for Intel 8080 processor and then executed by 8080 virtual machine. It has some similarities to today's Java platform and it is also the main cause of low performance of DBC-created code.