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// SPDX-License-Identifier: GPL-2.0
/*
 * shebang_origin.bpf.c - $ORIGIN-relative shebang (#!) interpreter resolution.
 *
 * A binfmt_misc_ops handler for scripts whose interpreter line is
 * "#!$ORIGIN/...": the interpreter is resolved relative to the directory of
 * the script and selected via bpf_binprm_set_interp(). Ordinary scripts are
 * declined so binfmt_script handles them.
 *
 * The whole shebang line is in the prefetched bprm->buf, so no file read is

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{
  description = "Linux Kernel Development Environment";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.11";
  };

  outputs = {
    self,
    nixpkgs,

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// SPDX-License-Identifier: GPL-2.0
/*
 * binfmt_misc 'B' (BPF) program: match aarch64 ELF binaries and choose the
 * interpreter (qemu-aarch64) dynamically via bpf_binprm_set_interp().
 *
 * The program is given the BINPRM_BUF_SIZE file header as context. It inspects
 * the ELF header and, on a match, sets the interpreter and returns 1. This
 * makes the handler a superset of a traditional magic rule: the program both
 * decides the match and computes the interpreter path (it could equally derive
 * a path relative to the binary).

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package main

import (
	"encoding/json"
	"fmt"
	"os"
	"os/exec"
	"strings"
)

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Cache-Aware Struct Benchmarks

Benchmarks demonstrating how struct size and memory layout affect performance due to CPU cache behavior. Companion code for the blog post Every byte matters.

Benchmarks

1. Pointer-Chasing (cache staircase)

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ClassPathInfo = provider(
    "Provider for classpath information",
    fields = {
        "compile_jars": "A json fragment containing the mapping of the current jar to its source jar",
    },
)

def _classpath_aspect_impl(target, ctx):
    java_info = target[JavaInfo]
    compile_jars = depset(

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"""
FlatBuffer Java rule for Bazel
"""

FlatbufferInfo = provider(
    doc = "A provider for FlatBuffer schema files.",
    fields = {
        "fbs_files": "The list of fbs files that were used as inputs",
    },
)

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genrule(
    name = "check_cgroup",
    outs = ["cgroup_output.txt"],
    cmd = """
        set -euo pipefail

        echo "==== /proc/self/cgroup ====" > $@
        cat /proc/self/cgroup >> $@
        echo "" >> $@

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#! /usr/bin/env python3

import subprocess
import re
import datetime
from collections import defaultdict, Counter
import argparse
import os
import sys

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import sys
import os
from xml.etree import ElementTree as ET
from xml.dom import minidom

# Usage: python gen_classpath.py jars.txt /path/to/bazel/workspace

def find_binary_jar(source_jar):
    """Replace '-sources.jar' or '-src.jar' with '.jar' or 'lib' prefix if necessary"""
    dir_name, file_name = os.path.split(source_jar)