[PATCH v3] gen_compile_commands: handle multiple lines per .mod file

From: John Hubbard
Date: Mon Jun 27 2022 - 21:24:06 EST


scripts/clang-tools/gen_compile_commands.py incorrectly assumes that
each .mod file only contains one line. That assumption was correct when
the script was originally created, but commit 9413e7640564 ("kbuild:
split the second line of *.mod into *.usyms") changed the .mod file
format so that there is one entry per line, and potentially many lines.

The problem can be reproduced by using Kbuild to generate
compile_commands.json, like this:

make CC=clang compile_commands.json

In many cases, the problem might be overlooked because many subsystems
only have one line anyway. However, in some subsystems (Nouveau, with
762 entries, is a notable example) it results in skipping most of the
subsystem.

Fix this by fully processing each .mod file.

Fixes: 9413e7640564 ("kbuild: split the second line of *.mod into *.usyms")
Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
---

Link to v2:
https://lore.kernel.org/all/20220616021149.327587-1-jhubbard@xxxxxxxxxx/

Changes since v2:

* Restored a blank line.

* Rewrote the commit description.

thanks,
John Hubbard


scripts/clang-tools/gen_compile_commands.py | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/scripts/clang-tools/gen_compile_commands.py b/scripts/clang-tools/gen_compile_commands.py
index 1d1bde1fd45e..47da25b3ba7d 100755
--- a/scripts/clang-tools/gen_compile_commands.py
+++ b/scripts/clang-tools/gen_compile_commands.py
@@ -157,10 +157,10 @@ def cmdfiles_for_modorder(modorder):
if ext != '.ko':
sys.exit('{}: module path must end with .ko'.format(ko))
mod = base + '.mod'
- # The first line of *.mod lists the objects that compose the module.
+ # Read from *.mod, to get a list of objects that compose the module.
with open(mod) as m:
- for obj in m.readline().split():
- yield to_cmdfile(obj)
+ for mod_line in m:
+ yield to_cmdfile(mod_line.rstrip())


def process_line(root_directory, command_prefix, file_path):
--
2.36.1