[PATCH 1/5] bootlinux: emit compile_commands.json into the kernel source tree

From: Daniel Gomez <[email protected]>

The direct-boot path builds the kernel out-of-tree into
BOOTLINUX_DIRECT_BOOT_BUILDDIR, so the .cmd files clangd, cscope,
and IDEs depend on land outside the source tree and the consumers
never find them. Run the kernel's own
scripts/clang-tools/gen_compile_commands.py after the build with
--directory pointed at the build dir and --output pointed at
$TREE_PATH/compile_commands.json, matching the invocation the
upstream script documents.

Gated by CONFIG_BOOTLINUX_DIRECT_BOOT_COMPILE_COMMANDS (default y).
Idempotent; rerunning rewrites the file from the current .cmd
contents.

Generated-by: Claude AI
Signed-off-by: Daniel Gomez <[email protected]>
---
 playbooks/roles/bootlinux/tasks/build/direct-boot.yml | 16 ++++++++++++++++
 workflows/linux/Kconfig                               | 15 +++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/playbooks/roles/bootlinux/tasks/build/direct-boot.yml b/playbooks/roles/bootlinux/tasks/build/direct-boot.yml
index 39263570..eadcbfbf 100644
--- a/playbooks/roles/bootlinux/tasks/build/direct-boot.yml
+++ b/playbooks/roles/bootlinux/tasks/build/direct-boot.yml
@@ -147,6 +147,22 @@
   delegate_to: localhost
   tags: [build-linux]
 
+- name: Generate compile_commands.json in the kernel source tree
+  ansible.builtin.command:
+    argv:
+      - ./scripts/clang-tools/gen_compile_commands.py
+      - --directory
+      - "{{ bootlinux_direct_boot_builddir }}"
+      - --output
+      - "{{ bootlinux_direct_boot_tree_path }}/compile_commands.json"
+    chdir: "{{ bootlinux_direct_boot_tree_path }}"
+  changed_when: true
+  when:
+    - bootlinux_direct_boot_compile_commands | default(true) | bool
+  run_once: true
+  delegate_to: localhost
+  tags: [build-linux]
+
 # `make install` runs /sbin/installkernel against the controller's
 # /boot and may need root. Copy the image into the destdir by hand.
 - name: Resolve the built kernel image path
diff --git a/workflows/linux/Kconfig b/workflows/linux/Kconfig
index 317c2073..117dd464 100644
--- a/workflows/linux/Kconfig
+++ b/workflows/linux/Kconfig
@@ -162,6 +162,21 @@ config BOOTLINUX_DIRECT_BOOT_DESTDIR
 	  virtiofs-shares lib/modules into the imageless nixos-flake
 	  closure at runtime.
 
+config BOOTLINUX_DIRECT_BOOT_COMPILE_COMMANDS
+	bool "Generate compile_commands.json into the kernel source tree"
+	output yaml
+	default y
+	help
+	  After the kernel build, run
+	  scripts/clang-tools/gen_compile_commands.py against the
+	  out-of-tree build directory and write the resulting JSON
+	  index to BOOTLINUX_DIRECT_BOOT_TREE_PATH/compile_commands.json.
+	  Lets clangd, cscope, and IDEs pick up the build's
+	  translation-unit set without further setup. The step is
+	  idempotent; rerunning rewrites the file from the current
+	  .cmd contents. Disable to skip (a few seconds on a large
+	  build).
+
 endif # BOOTLINUX_DIRECT_BOOT
 
 if BOOTLINUX_9P

-- 
2.54.0