# ARM-software/abi-aa

Application Binary Interface for the Arm® Architecture

Repository: https://github.com/ARM-software/abi-aa
Canonical: https://ross.abutalabs.com/products/abi-aa
Language: HTML
License: NOASSERTION
License Family: other
Last push: 2026-08-25T09:33:05+00:00

## Health v2 (maintenance only)
Score: 67/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 99, release rhythm 8, longevity 100
- inputs: {"age_days": 2500, "days_push": 8, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1256, forks 228 (observed 2026-08-28T04:04:08.965305+00:00)

## What it is
The official repository of Application Binary Interface (ABI) specification documents for the Arm architecture, covering 32-bit and 64-bit (AArch64) standards such as the procedure call standard, ELF, DWARF, and C++ ABI. It hosts source files and officially released documents under a Creative Commons license.

## Use cases
- find the Arm procedure call standard (AAPCS) specification
- look up the ELF ABI rules for Arm 64-bit
- check calling conventions for AArch64 function arguments
- reference the C++ ABI for Arm architecture
- report a defect in an Arm ABI specification
- download the latest official Arm ABI documents

## When to choose
- you are building a compiler, linker, debugger, or OS targeting Arm and need authoritative ABI rules
- you need the official procedure call standard or ELF/DWARF details for Arm 32-bit or 64-bit
- you want to file or track ABI specification issues with Arm

## When to avoid
- you need executable tools or libraries rather than specification documents
- you need ABIs for non-Arm architectures such as x86 or RISC-V
- you need legacy proprietary-licensed document versions not hosted here

## Facets
- artifact type: dataset
- maturity: active
- function: documentation, compiler, developer-tools
- domain: documentation, compilers, operating-systems, developer-tools
- platform: cross-platform
- tags: arm-architecture, abi-specification, aapcs, elf, calling-convention, specification-documents, arm

## Member repositories
- ARM-software/abi-aa (main) score 67

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:08.965305+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T05:07:13.915619+00:00, confidence not recorded.
  - readme: https://github.com/ARM-software/abi-aa (fetched 2026-08-28T04:04:08.965305+00:00, sha 080c379d88ed)
- Data as of 2026-08-30T08:39:29.467469+00:00.