c-cpp-knowledge-patch

A reference guide for C and C++, two programming languages commonly used for system software. It covers compiler versions, language standards, libraries, modules, sanitizers, diagnostics, and binary compatibility.

In plain words
What is it for?
Use it when upgrading Clang or GCC, changing language modes, diagnosing compiler regressions, configuring sanitizers or analysis tools, or reviewing ABI boundaries.
Why use it?
It helps prevent build and compatibility problems caused by mismatched compilers, language settings, libraries, or binary interfaces.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/nevaberry/nevaberry-plugins/c-cpp-knowledge-patch
Any agent
npx skills add Nevaberry/nevaberry-plugins --skill c-cpp-knowledge-patch
Clone the repo
git clone --depth 1 https://github.com/Nevaberry/nevaberry-plugins

Made for: Claude Code, Codex.

Per session 12 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,379 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00012 $0.02379
Opus 5 $0.00006 $0.01189
Sonnet 5 $0.00002 $0.00476
Haiku 4.5 $0.00001 $0.00238

Measured 2d ago against content hash 3c58039ee72a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

c-cpp-knowledge-patch scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

plugins/knowledge-patch/patches-claude/c-cpp-knowledge-patch/SKILL.md · 218 lines

How it starts

The opening of the file, as written. The whole thing — 218 lines — stays where its author put it; the contents beside it link to each section on GitHub.

C and C++ compatibility guidance

Use this skill when upgrading Clang, GCC, libclang, libstdc++, or C/C++ language modes; diagnosing a compiler-version regression; changing modules, sanitizers, static analysis, formatting, offloading, or target options; or reviewing an ABI boundary built with different toolchain versions.

Treat the project as the source of truth. Inspect its compiler constraints, dialect flags, target triples, standard-library selection, warning policy, sanitizer configuration, module pipeline, and ABI consumers before applying a compatibility switch. Prefer a source migration or a consistent rebuild over leaving a legacy switch in place indefinitely.

Topic index

Reference Read when working on
C language and standards C23/C2y modes, C compatibility, declarations, initialization, and conformance gaps
C++ language and modules C++20/23/26/29 features, constexpr, templates, modules, coroutines, and dialect defaults
Diagnostics and tooling warnings, machine-readable diagnostics, clang-format, libclang, AST matchers, plugins, and the Static Analyzer
Libraries, builtins, and attributes libstdc++, builtins, annotations, format checking, and allocation contracts
Migration and ABI mixed compiler objects, mangling, record layout, removed compatibility paths, and library ABI transitions
Optimization, debugging, and sanitizers aliasing, overflow, floating point, LTO, debug information, profiles, and sanitizer controls
Targets, offloading, and OpenMP CPU/OS targets, CUDA/HIP, OpenACC, WebAssembly, OpenMP, and architecture flags

Upgrade triage: breaking changes first

Pin the intended language dialect

Read the full file on GitHub · 218 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 218 lines · 12 tokens per session scan A 3c58039ee72a

Subscribe to this mod's changes

c-cpp-knowledge-patch is a skill published in the GitHub repository Nevaberry/nevaberry-plugins (24 stars, last pushed 5d ago), licensed MIT. It adds 12 tokens to every session and 2,379 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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