rg-asm release notes

The assembler and linker for Atari ST, TT and Falcon. Newest release first.

0.7.13 — 2026-09-26

Fixes mis-assemblies of register aliases in addressing modes, branches to keyword-named symbols, and nondeterministic object output.

Bug fixes

• Register aliases in pre-decrement and post-increment addressing: Register equates used as address registers (input EQUR a3, then move.b -(input),d6) resolve to the aliased register instead of reading as negative-displacement expressions.
• Branch instructions targeting keyword-named symbols: Branch instructions with offsets targeting symbols named after directives (bsr set+4, bra equ+8) assemble as branches rather than being parsed as equate definitions.
• Deterministic object output: Symbol table ordering in DRI and Pure C object file generation is now deterministic across build runs.

0.7.12 — 2026-09-23

Strict literal MOVEM preservation under non-optimizing mode.

Improvements

• Strict literal MOVEM assembly: Gated the single-register MOVEM -> MOVE peephole optimization behind its own size-optimization switch (active by default in the standard optimization profiles). Under --no-opt-size (-O0), explicit MOVEM.L <ea>,Rn instructions assemble verbatim as 0x4CDx without automatic folding to MOVE.L, enabling exact round-trip fidelity for disassembled source code.

0.7.11 — 2026-09-23

Fixes the glued Devpac define flag so the name keeps the case you typed.

Bug fixes

• Glued Devpac defines keep their spelling: -eFOO=7 now defines FOO, matching the separated -e FOO=7 form. Previously the glued form lower-cased the name to foo, so the two spellings of the same flag disagreed.

0.7.10 — 2026-09-20

Fixes memory indirect addressing parsing when PC is used as base with an index register.

Bug fixes

• Memory indirect PC-base addressing: Correctly parses ([0,PC,An]) and related memory indirect forms with PC base and an index register.

0.7.9 — 2026-09-20

Allows PC-relative destination operands on CMPI and clarifies the TST address register diagnostic.

Bug fixes

• CMPI with PC-relative destinations: Emits no warning on legal CMPI instructions reading PC-relative memory destinations (e.g. cmpi.b #$10,-4(PC)).
• TST address register diagnostic: Clarified that only byte size (TST.B An) is unencodable, while word and long sizes are supported on 68020+.

0.7.8 — 2026-09-17

Expands branch relaxation pass budget for large files and improves diagnostic messaging.

Bug fixes

• Branch relaxation budget: Increased default pass limit so large listings assemble without requiring --opt-relax-passes.
• Relaxation diagnostic: Clearly reports pass limits and the --opt-relax-passes=<N> override flag upon exhaustion.
• Zero-pass relaxation refusal: Refuses --opt-relax-passes=0 with a diagnostic rather than emitting unverified layouts.

0.7.7 — 2026-09-17

Refines TST address register checks against the declared target CPU architecture.

Bug fixes

• CPU-aware TST validation: Silences 68000-only warnings when assembling for 68020+ targets with .cpu 68020.

0.7.6 — 2026-09-13

Rejects shift and rotate counts that have no immediate encoding instead of silently assembling the wrong bytes.

Bug fixes

• Shift and rotate immediate bounds: Immediate counts outside 1..8 are rejected with an error rather than silently truncated to 3 bits.

0.7.5 — 2026-09-12

Added --summary flag (summary tables now off by default), display control flags (--color, --ascii, --banner), and graceful broken pipe handling on stdout.

Features

• Summary tables off by default (--summary): the section size and cycle total tables are now omitted unless --summary is passed on interactive stderr; --functions also enables the per-function breakdown.
• Display control flags: --color <auto|always|never> (honours NO_COLOR), --ascii for plain ASCII table borders, and --banner <logo|line|none> for masthead selection. --color=always keeps ANSI colour and boxed listings when piped into a pager such as less -R.

Bug fixes

• Broken stdout pipe: exits 0 instead of panicking when stdout is piped into head or less.

0.7.4 — 2026-09-09

Added .prgflags directive support for TOS executables.

Features

• PRG flags directive (.prgflags): Added .prgflags <expr> directive support, allowing source assembly to set the PRG flags in the generated .prg / .tos header.

0.7.3 — 2026-08-26

Test-infrastructure only: the shipped assembler is unchanged.

Improvements

• The test suite's scratch directories now remove themselves; the helper behind 44 tests never deleted them, leaving 177,488 on the build host.
• No assembler behaviour is affected — the change is confined to the test suite.

0.7.2 — 2026-08-25

Minor test suite hardening for deterministic non-terminal resolution.

Improvements

• Summary display precedence tests now resolve terminal capabilities explicitly.

0.7.1 — 2026-08-21

More floating-point coverage, a size-optimisation fix, and linker fixes for cases that could previously assemble or link to the wrong bytes. Default dialect output is unchanged.

New features

• FScc, FDBcc, and FTRAPcc now recognise and encode all 32 condition predicates, completing the FPU condition-code surface.
• Added a library option so callers that re-assemble their own listings can control instruction alignment independently of the selected dialect.
• Raw #{$w0,$w1,$w2} FPU immediates now also accept the 12-byte packed (.p) form, matching the packed listings produced for round-trip verification.

Bug fixes

• Invalid raw #{$...} floating-point immediates are now rejected instead of being silently dropped; previously the bytes after the instruction could be misaligned.
• --no-opt-size now keeps CMPA.L #n,An long as written; it was the one size transform that still fired with size optimisation disabled.
• Same-section PC-relative references are now recomputed by the linker when --relax is used, fixing cases where a function could resolve to a point inside itself.
• Expressions used as displacements now relocate correctly instead of turning into zero when they involve a symbol difference.
• A BSS section that references an external symbol now produces an error instead of silently dropping the reference.
• An unknown named section type is now reported as an error instead of being assembled into the current section.
• Named typed sections now keep their name where the output format supports it, so small-data sections can be placed by name.

Known issues

• With size optimisation enabled, an explicitly sized absolute address such as move.l ($52).l,d0 can still be shortened to word form; the explicit long form is currently treated as a size hint rather than a directive.

0.7.0 — 2026-07-29

Adds GenPC dialect support — Ziggy/OVR's PC cross-assembler (Overlanders). Use --dialect=genpc for GenPC and as68 sources.

New features

• --dialect=genpc: brace {/} macros, IF/WHILE/REPEAT, @ octal, Devpac-style text/end.
• Flat binary output with --raw; optional --reloc reloc-table trailer and --strip-bss tail trim.
• LS / LST symbol-file load; .SY2 overlay values when assembling with --reloc.

Improvements

• Default --dialect restored to vasm for Motorola-syntax sources.

Bug fixes

• GenPC: SY2 overlay reloc values, WHILE/REPEAT parse depth, and sizing defaults (forward branches word-sized, unsized MOVE defaults to word).

0.6.0 — 2026-07-27

Much broader dialect coverage and byte-level checks against classic Atari assemblers. Devpac, TurboAss, MADMAC, Alcyon and several other tools now have committed goldens; --strict-dialect catches foreign syntax more reliably.

New features

• Full-syntax corpora for TurboAss and DevpacST 1.01 (STANDARD / GenST TOS programs).
• Expanded MADMAC, Alcyon AS68, Lattice, SEKA, GST-ASM and other dialect packs with host oracles.
• Dialects and smoke harnesses for additional vendored assemblers (Sozobon, Josy, Brainstorm, MWC, AssemPro, GFA).
• LLVM-flavoured GAS ingestion path and a gas-llvm corpus.
• Aztec C Mot ingestion with a self-golden DRI pin (native ST AS.TTP still not available).

Improvements

• GenST / TurboAss --prg output matches classic empty-DATA and reloc trailers more closely.
• --strict-dialect promotes foreign-syntax heuristics to hard errors across dialects.
• Rejection checklists and negatives across all 22 dialect coverage matrices.

Bug fixes

• Fixed empty-DATA padding when text length was 2 mod 4 (vlink-style pad) for GenST-family and TurboAss programs.
• GenST 1.01 treats | as a line comment; ENDC handling matches the era.

0.5.6 — 2026-07-24

Added more vasm Mot and Pure C dialect coverage, and fixed a macro expansion crash. Building the macOS release no longer needs CoreFoundation.

New features

• Broader vasm Mot syntax: nested \@! / \@@ stacks, -allmp for args 10–35, include / offset / section, data aliases and conditionals.
• Pure C MACRO name.size sized-macro expansion, plus SET / EQU / MACRO / REPT / CPU coverage.
• Pure C object names and FIX tables closer to PASM.

Bug fixes

• Macro .size and \?0 expansion no longer panics.
• Dropped the chrono dependency so macOS cross-builds do not need CoreFoundation.

0.5.5 — 2026-07-22

Added support for additional dialects and improved the size optimiser. rg-asm now understands far more of RMAC's syntax, produces tighter code at the higher optimisation levels, and lays out Devpac-style object files more faithfully.

New features

• Much broader support for RMAC-style source, including its higher optimisation levels.
• Tighter code from the size optimiser: some absolute memory accesses become shorter PC-relative forms.
• Improved Devpac-compatible object output and listing formatting.

Bug fixes

• Fixed a false error on some forward references in indexed PC-relative addressing.
• More accurate instruction timing for immediate-to-register arithmetic.
• Corrected a few object-file layout details for better interoperability with other tools.

0.5.1 — 2026-07-20

Added a machine-readable JSON mode and an optional per-function size/timing table. Also fixed a pile of linker bugs — cases that used to emit subtly wrong programs now either work correctly or stop with a clear error.

New features

• A --json mode that prints one structured document you can feed to other tools.
• An optional --functions table showing the size and cycle cost of each function.

Bug fixes

• Fixed several linking bugs that could silently produce incorrect programs.
• Out-of-range jumps, bad relocations, and malformed flat images now stop with a clear error instead of emitting wrong bytes.

Breaking changes

• With no -o, the output file is now named after the input (main.s → main.prg) instead of always out.tos. Pass -o out.tos to keep the old name.
• The --summary options were replaced by --functions (the per-function table), -q (quiet), and --json (machine-readable).
• A few command-line flags were renamed for consistency; see the manual for the current names.
• The separate manual and man page were folded into the README that ships with the download.

0.1.0 — 2026-06-01

First public release. One self-contained assembler and linker for Atari ST and Falcon development — runs natively on Linux, macOS and Windows with nothing else to install. Free and open source (MIT or Apache-2.0).

New features

• Assembles Motorola syntax plus seven other classic assembler dialects, detected automatically per file.
• Links directly to ready-to-run Atari .TOS / .PRG programs.
• Supports the full 680x0 line (68000–68060) and ColdFire instruction sets, floating-point targets, and a size optimiser.
• Reads and writes six common Atari object-file formats (DRI, GST, Pure C, SEKA, a.out, and ELF), so it mixes cleanly with other toolchains.

Known issues

• A handful of 68030 memory-management instructions are recognised but not yet assembled; rg-asm reports an error for them rather than risk emitting wrong code.