oscar64(1)

💖 NAME 💖

okay bestie, this is oscar64(1) from the User Commands manual, and the NAME line is literally: oscar64 — optimizing C/C++ cross-compiler for 6502 systems. That’s the whole vibe. ✨

🌈 SYNOPSIS 🌈

oscar64 [-h] [-v[1|2|3]] {-i=includePath} [-ii=includePath]
       [-o=output.prg] [-rt=runtime.c] [-tf=format] [-tm=machine] [-pp]
       [-strict] [-psci] [-n|-bc] [-e[p|t|b|a|i]] [-g[p]] [-O(0|1|2|3|s)]
       [-O(i|ii|a|z|p|o|x|g|m)] [-dSYMBOL[=value]] [-DSYMBOL[=value]] [-xz]
       [-rmp] [-d64=diskname] [-f=file] [-fz=file] [-fi=n] [-cid=n] [-csub=n]
       [-cname=name] {source.c} {source.cpp}

🎀 DESCRIPTION 🎀

oscar64 is a C/C++ compiler for the 6502 processor family. It is designed to generate high-performance 8-bit code targeting platforms such as the Commodore 64, VIC-20, PET, Commander X16, NES, Atari 8-bit, and Mega65. High-performance 8-bit code, bestie — that’s the whole point. 💅

✨ OPTIONS ✨

🫶 General Options

• -h — Print help text and exit. Like a little “what do I do now?” button. 💖
• -i=includePath — Set the include file search path.
• -ii=includePath — Set the default include path (overrides built-in path).
• -o=output.prg — Specify output file name.
• -rt=runtime.c — Use a custom runtime startup source (or empty for none).
• -pp — Compile in C++ mode (automatically enabled for .cpp files).
• -strict — Use strict ANSI C parsing (no C++ extensions).
• -psci — Use PETSCII encoding for all string literals without prefix.
• -xz — Extended zero page usage. Provides more zero page space but disables return to BASIC. More space, but no cozy return-to-BASIC moment — noted.
• -rmp — Generate error files (.error.map and .error.asm) when the linker fails.

🧚 Symbol Definitions

• -dSYMBOL[=value] — Define a preprocessor symbol (like -D in other compilers).
• -DSYMBOL[=value] — Define a symbol in a gcc-compatible way (e.g., -D NAME=VALUE as a separate argument).

🔥 Code Generation

• -n — Create pure native code for all functions (now the default).
• -bc — Create byte code for all functions (disables native code generation).
• -e — Execute the result in the integrated emulator after compilation.
• -ep — Execute and profile the result in the integrated emulator.
• -et — Execute with trace output in the integrated emulator.
• -eb — Execute with break trace in the integrated emulator.
• -ea — Execute with asserts enabled in the integrated emulator.
• -ei — Execute with I/O range checking in the integrated emulator.

👑 Optimization

• -O0 — Disable all optimizations.
• -O1 or -O — Default optimizations.
• -O2 — Aggressive speed optimizations (includes auto-inline of small functions).
• -O3 — Aggressive optimization for speed (includes all sub-optimizations).
• -Os — Optimize for code size.
• -Oi — Enable auto-inline of small functions (part of O2/O3).
• -Oii — Enable aggressive auto-inline of all suitable functions.
• -Oa — Optimize inline assembler (part of O2/O3).
• -Oz — Enable auto-placement of global variables in zero page (part of O3).
• -Op — Optimize constant parameters.
• -Oo — Optimize size using "outliner" (extract repeated code sequences into functions).
• -Ox — Optimize pointer arithmetic by blocking shorter arrays from crossing page boundaries.
• -Og — Enable global optimization.
• -Om — Enable merge calls optimization.

🌸 Debug and Diagnostics

• -v — Enable verbose output for diagnostics.
• -v2 — More verbose output.
• -v3 — Even more verbose output (implies v2).
• -g — Create source-level debug info and add source line numbers to .asm listing.
• -gp — Create source-level debug info and static profile data.

🦋 Target Format

• -tf=format — Set the output target format.
  • prg — Standard Commodore PRG format (default).
  • crt — EasyFlash cartridge format.
  • crt8 — Generic 8KB cartridge (0x8000-0xa000).
  • crt16 — Generic 16KB cartridge (0x8000-0xc000).
  • bin — Raw binary format.
  • lzo — LZO-compressed PRG output.

💜 Target Machine

• -tm=machine — Specify the target machine.
  • c64 — Commodore C64 (0x0800..0xa000, default).
  • c128 — Commodore C128 (0x1c00..0xfc00).
  • c128b — C128 first 16KB only (0x1c00..0x4000).
  • c128e — C128 first 48KB only (0x1c00..0xc000).
  • plus4 — Commodore Plus/4 (0x1000..0xfc00).
  • vic20 — VIC-20, no expansion (0x1000..0x1e00).
  • vic20+3 — VIC-20 +3K RAM (0x0400..0x1e00).
  • vic20+8 — VIC-20 +8K RAM (0x1200..0x4000).
  • vic20+16 — VIC-20 +16K RAM (0x1200..0x6000).
  • vic20+24 — VIC-20 +24K RAM (0x1200..0x8000).
  • pet — Commodore PET, 8K RAM (0x0400..0x2000).
  • pet16 — Commodore PET, 16K RAM (0x0400..0x4000).
  • pet32 — Commodore PET, 32K RAM (0x0400..0x8000).
  • nes — NES NROM, 32K ROM, no mirror.
  • nes_nrom_h — NES NROM, 32K ROM, horizontal mirror.
  • nes_nrom_v — NES NROM, 32K ROM, vertical mirror.
  • nes_mmc1 — NES MMC1 mapper, 256K PROM, 128K CROM.
  • nes_mmc3 — NES MMC3 mapper, 512K PROM, 256K CROM.
  • atari — Atari 8-bit systems (0x2000..0xbc00).
  • x16 — Commander X16 (0x0800..0x9f00).
  • mega65 — Mega65 (0x2000..0xc000).

🍓 Disk Image

• -d64=diskname — Create a .d64 disk image with the specified name.
• -f=file.xxx — Add a binary file to the disk image.
• -fz=file.xxx — Add a compressed binary file to the disk image.
• -fi=n — Set sector interleave for data files on disk image (default: 10).

🎀 Cartridge Options

• -cid=n — Set cartridge type ID (used by VICE emulator).
• -csub=n — Set cartridge sub-type.
• -cname=name — Set cartridge name string.

💖 RUNTIME LIBRARY DEFINES 💖

• -dNOLONG — Disable support for long integers in printf.
• -dNOFLOAT — Disable floating-point support in printf.
• -dHEAPCHECK — Enable heap allocation/free checking; jam if heap is full or free out of range.
• -dNOBSSCLEAR — Do not clear BSS segment on startup.
• -dNOZPCLEAR — Do not clear zero-page BSS segment on startup.

🌟 EXAMPLES 🌟

Compile a program with optimizations:

oscar64 -i=include -O2 -o=demo.prg demo.c

Compile with emulator execution and custom runtime:

oscar64 -e -rt=startup.c -f=assets.dat game.c

Create a disk image with compiled output:

oscar64 -d64=mydisk.d64 -f=demo.prg demo.c

Compile in C++ mode with maximum optimization:

oscar64 -pp -O3 -o=demo.prg demo.cpp

🧚 FILES 🧚

• /nix/store/3ja2prlv2pld7z2khswfy7lpwaq4riwx-oscar64-1.32.273/bin/oscar64 — Main compiler executable.
• /nix/store/3ja2prlv2pld7z2khswfy7lpwaq4riwx-oscar64-1.32.273/include/oscar64 — Headers and startup runtime source.

👀 SEE ALSO 👀

llvm-mos(1)

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mwah 💋 that’s the whole page, bestie. This was oscar64(1), Version 1.32, dated June 2026 — version 1.32, June 2026, oscar64(1), periodt. 🫶✨🎀