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Run the Assembly Test Suite and Triage Failures with Atlas in 2026

Updated 7 min read

Atlas helps Assembly developers in 2026 transform a wall of red `make check` test output into a prioritized list of distinct root causes by running the suite, capturing full logs, and using `grep` to group failures before tracking fixes with `todowrite`.

How to run `make check` for Assembly with Atlas and capture full test logs

In 2026, Assembly developers initiate their test suites using Atlas's `bash` tool, which executes `make check` and ensures complete log capture. This prevents truncation of verbose output, a common issue when debugging complex x86-64 or ARM64 failures.

When an Assembly developer needs to run their project's test suite, Atlas's `bash` tool provides the necessary execution environment. By issuing a command like `atlas bash "make check"`, Atlas executes the standard Assembly test runner. A critical feature for Assembly development is Atlas's handling of test output: while the terminal display is truncated at 2000 lines or 50 KB to maintain readability, the complete log is always written to a retained file. Atlas then provides the exact path to this file, ensuring that no detail from a lengthy `make check` run is lost. This full log is essential for diagnosing intricate issues in `.asm` or `.S` sources, especially when dealing with the nuances of register allocation or calling conventions on x86-64 and ARM64 architectures.

Grouping Assembly `make check` failures by root cause using Atlas

Atlas assists Assembly developers in 2026 in transforming raw `make check` output into actionable insights by grouping failures by distinct root causes, rather than individual test names. This process leverages `grep` on the complete log file.

After running `make check` and obtaining the full test log, the next step for an Assembly developer is to identify the underlying root causes of failures. Atlas facilitates this by allowing the use of its `grep` tool on the saved log file. Instead of sifting through hundreds of individual test failures, developers can search for common error patterns, such as specific register conflicts, incorrect stack alignment, or ABI violations. For instance, a `grep` command targeting a particular linker error message or a common runtime exception signature can quickly reveal how many tests are failing due to the same fundamental problem. This method is far more efficient than grouping by test name, as multiple tests often expose the same underlying bug in a shared Assembly routine or a common misinterpretation of a System V or AAPCS64 calling convention.

Prioritizing and tracking Assembly test fixes with Atlas `todowrite`

To ensure no Assembly test failure is forgotten, Atlas in 2026 enables developers to record each distinct root cause as a `todowrite` entry. This creates a prioritized list, allowing focused resolution of issues impacting x86-64 or ARM64 code.

Once distinct root causes for Assembly test failures have been identified using `grep`, Atlas's `todowrite` tool becomes invaluable for managing the remediation process. For each unique problem, an Assembly developer can create a `todowrite` entry, setting its status to 'pending'. This transforms a wall of red output into a structured, prioritized list of tasks. For example, an entry might be 'Fix x86-64 stack alignment issue in `my_routine.asm`' or 'Correct ARM64 register usage in `crypto_func.S`'. Developers then address these issues one at a time using `atlas edit <file.asm>`. After each modification, Atlas allows re-running only the affected tests via `bash`, significantly accelerating the debug cycle compared to executing the entire `make check` suite repeatedly. This focused approach ensures efficient and systematic resolution of Assembly code defects.

How Atlas ensures safe Assembly code changes and review

Atlas provides multiple layers of safety for Assembly developers in 2026, from permission-gated tool calls to unified diffs for every file edit. This ensures that changes to critical x86-64 or ARM64 code are always reviewed and approved.

Working with Assembly code, especially on x86-64 and ARM64 architectures, demands precision and careful review. Atlas integrates several safety mechanisms to protect against unintended modifications. Every Atlas tool call, including `bash`, `edit`, or `grep`, is permission-gated, requiring explicit 'allow', 'ask', or 'deny' rules before execution. Furthermore, Atlas drafts a plan in a read-only plan agent and seeks approval before switching to a build agent to make any changes. When an Assembly file is modified, Atlas computes a unified diff for every edit and surfaces it for approval, giving the developer full control over what gets written. Atlas also reads git branches, status, and diffs, and can stage and create commits on your behalf, with the ability to snapshot file changes as git patches for easy diffing and rolling back of edits.

Atlas's deep understanding of Assembly language specifics

Atlas in 2026 is designed with a profound understanding of Assembly language, including x86-64 and ARM64 architectures. It can analyze register allocation, calling conventions (System V, AAPCS64), and the ABI, providing context for debugging and refactoring.

Atlas's effectiveness in triaging Assembly test failures stems from its deep linguistic understanding. It indexes code by AST declarations using tree-sitter, allowing it to comprehend the structure of `.asm` or `.S` files, including sections, labels, and the specific calling conventions each routine honors, such as System V for x86-64 or AAPCS64 for ARM64. This contextual awareness means Atlas can do more than just run commands; it can explain a hot loop, annotate register usage before suggesting changes, and even help maintain code style with `asmfmt`. When Atlas assembles code with `nasm` or the GNU assembler and runs harnesses under `make check`, it does so with an informed perspective on the intricate contracts of register allocation and the ABI, making its assistance highly relevant to Assembly developers.

Step by step

  1. 01Run the Assembly test suite with Atlas's `bash` tool: Execute `atlas bash --timeout 300000 "make check"` to prevent premature termination of a slow x86-64 or ARM64 test run.
  2. 02Access the complete Assembly test log: If Atlas reports "...output truncated...", use `atlas read <path/to/full_log.txt>` to view the entire `make check` output, ensuring no critical failure details are missed.
  3. 03Group Assembly failures by distinct root cause: Employ `atlas grep "error pattern"` on the saved log file to identify common failure signatures, such as specific register misuse or ABI violations, rather than individual test names.
  4. 04Record distinct Assembly root causes as `todowrite` entries: For each unique failure pattern identified, create a `todowrite` entry, e.g., `atlas todowrite "Fix x86-64 stack alignment issue" --status pending`, to track the required fixes.
  5. 05Fix Assembly issues one by one with `edit`: Use `atlas edit <file.asm>` to modify the relevant Assembly source file, addressing one root cause at a time.
  6. 06Re-run affected Assembly tests with `bash`: After each fix, use `atlas bash "make check <specific_test_target>"` to validate the change, focusing only on the tests impacted by the modification, rather than the entire suite.
  7. 07Format touched Assembly files with `asmfmt`: Before committing, ensure code style consistency by running `atlas bash "asmfmt <file.asm>"` on any modified Assembly files.

Frequently asked questions

How does Atlas handle large `make check` output for Assembly?
Atlas's `bash` tool truncates verbose `make check` output at 2000 lines or 50 KB in the terminal, but always writes the complete log to a retained file, providing its path for full review.
Can Atlas help me find the root cause of an x86-64 Assembly test failure?
Yes, Atlas helps you group `make check` failures by root cause using `grep` on the complete log, allowing you to identify patterns like specific register misuse or ABI violations in your x86-64 Assembly code.
How does Atlas ensure I don't forget about Assembly test failures?
Atlas's `todowrite` tool allows you to record each distinct Assembly root cause as a pending task, creating a prioritized list of fixes that are tracked until resolution.
Does Atlas understand Assembly-specific concepts like calling conventions?
Absolutely. Atlas indexes Assembly code by AST declarations, understanding x86-64 and ARM64 register allocation, System V and AAPCS64 calling conventions, and the ABI, providing deep contextual awareness.
How does Atlas prevent accidental changes to my critical Assembly code?
Atlas employs permission-gated tool calls, drafts plans in a read-only agent, and computes a unified diff for every file edit, requiring your explicit approval before writing any changes to your Assembly sources.
Can Atlas help me maintain `asmfmt` style in my Assembly project?
Yes, Atlas can be instructed to keep alignment and column style consistent with `asmfmt` on any Assembly files it touches, ensuring your codebase adheres to established formatting standards.
What Assembly toolchains does Atlas support for testing?
Atlas supports assembling your `.asm` or `.S` sources with `nasm` or the GNU assembler, and running your test harness under `make check` behind a permission prompt.

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