refactor(build): compile_commands.json architecture redesign + nlohmann::json#25
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Sunrisepeak wants to merge 6 commits into
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refactor(build): compile_commands.json architecture redesign + nlohmann::json#25Sunrisepeak wants to merge 6 commits into
Sunrisepeak wants to merge 6 commits into
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Extract compute_cxxflags() and compute_cflags() from emit_ninja_string() into standalone helper functions in the anonymous namespace. These helpers encapsulate all flag computation logic (PIC, sysroot, binutils, musl opt, include dirs, user flags) and will be reused by compile_commands.json generation in a follow-up commit. The ninja output is byte-identical to before the refactoring.
Automatically emit a Clang-compatible compile_commands.json to the target/ directory on every mcpp build. The JSON includes all compile units (project + dependencies) with exact compiler commands, matching the flags used by the ninja backend. - Add json_escape() helper for JSON string escaping - Add emit_compile_commands_json() using shared flag helpers - Wire into NinjaBackend::build() after build.ninja generation
Architecture redesign on top of PR #24's compile_commands.json feature: 1. `src/build/flags.cppm` (NEW) — shared compile/link flag computation. One definition consumed by both ninja backend and compile_commands emitter (and future backends). Eliminates the duplicated compute_cxxflags/compute_cflags functions. 2. `src/build/compile_commands.cppm` (NEW) — generates compile_commands.json using nlohmann::json (no manual string escaping). Uses `arguments` array format (clangd recommended). Writes to <projectRoot>/compile_commands.json for zero-config clangd. Incremental: skips write if content unchanged. 3. `src/libs/json.cppm` + `src/libs/json/json.hpp` (NEW) — nlohmann/json single-header library wrapped as C++23 module, copied from openxlings/xlings. MIT license. 4. `src/build/ninja_backend.cppm` — slimmed: imports flags.cppm, delegates compile_commands to its module, removes ~200 lines of duplicated flag computation. 5. `.agents/docs/2026-05-12-compile-commands-design.md` — design doc. 6. `.gitignore` — add compile_commands.json (generated). 7. `mcpp.toml` — add `include_dirs = ["src/libs/json"]` for json.hpp. All code formatted with .clang-format from PR #24.
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Summary
Builds on top of PR #24's compile_commands.json feature with proper architecture:
New modules
src/build/flags.cppm— shared flag computation (one definition, multiple consumers)src/build/compile_commands.cppm— JSON emitter using nlohmann::json (argumentsarray format)src/libs/json.cppm+json.hpp— nlohmann/json C++23 module wrapper (from xlings)Changes
ninja_backend.cppmslimmed ~200 lines (usesflags.cppm)compile_commands.jsonusesargumentsarray (clangd recommended) instead ofcommandstring<projectRoot>/(clangd zero-config).clang-formatDesign doc
.agents/docs/2026-05-12-compile-commands-design.mdRelationship to PR #24
This branch includes PR #24's commits (
.clang-format,.gitignore.sisyphus, initialcompile_commands.json). The refactor commit sits on top without modifying the original commits.Test plan
compile_commands.jsongenerated: 39 entries, valid JSON,argumentsformat.clang-formatapplied to all new/modified files