Re: [PATCH v2] scripts/clang-tools: Handle included .c files in gen_compile_commands

[Eduard Zingerman <eddyz87@gmail.com>]

On Tue, 2025-10-07 at 20:45 -0400, Pat Somaru wrote:
> The gen_compile_commands.py script currently only creates entries for the
> primary source files found in .cmd files, but some kernel source files
> text-include others (i.e. kernel/sched/build_policy.c).
> 
> This prevents tools like clangd from working properly on text-includedd c
> files, such as kernel/sched/ext.c because the generated compile_commands.json
> does not have entries for them.
> 
> Extend process_line() to detect when a source file includes .c files, and
> generate additional compile_commands.json entries for them. For included c
> files, use the same compile flags as their parent and add their parents headers.
> 
> This enables lsp tools like clangd to work properly on files like
> kernel/sched/ext.c
> 
> Signed-off-by: Pat Somaru <patso@likewhatevs.io>
> Tested-by: Justin Stitt <justinstitt@google.com>
> ---

I tested navigation to work in emacs+clangd combination with this
patch for the following files:
- kernel/sched/pelt.c
- kernel/sched/cputime.c
- kernel/sched/deadline.c

All included from the kernel/sched/build_policy.c.
Navigation works for entities declared in the same file, entities
declared in headers included from build_policy.c, entities declared in
headers included from {pelt,cputime,deadline}.c.

Note that sched/ code [ab]uses the pattern with .c file includes a
lot. W/o this patch clangd is completely oblivious to the content of
the above files. Jump to definition is almost useless, who-calls
queries ignore functions declared in these files etc.

Tested-by: Eduard Zingerman <eddyz87@gmail.com>

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