linux/scripts
Tom Roeder b302046401 scripts: add a tool to produce a compile_commands.json file
The LLVM/Clang project provides many tools for analyzing C source code.
Many of these tools are based on LibTooling
(https://clang.llvm.org/docs/LibTooling.html), which depends on a
database of compiler flags. The standard container for this database is
compile_commands.json, which consists of a list of JSON objects, each
with "directory", "file", and "command" fields.

Some build systems, like cmake or bazel, produce this compilation
information directly. Naturally, Makefiles don't. However, the kernel
makefiles already create .<target>.o.cmd files that contain all the
information needed to build a compile_commands.json file.

So, this commit adds scripts/gen_compile_commands.py, which recursively
searches through a directory for .<target>.o.cmd files and extracts
appropriate compile commands from them. It writes a
compile_commands.json file that LibTooling-based tools can use.

By default, gen_compile_commands.py starts its search in its working
directory and (over)writes compile_commands.json in the working
directory. However, it also supports --output and --directory flags for
out-of-tree use.

Note that while gen_compile_commands.py enables the use of clang-based
tools, it does not require the kernel to be compiled with clang. E.g.,
the following sequence of commands produces a compile_commands.json file
that works correctly with LibTooling.

make defconfig
make
scripts/gen_compile_commands.py

Also note that this script is written to work correctly in both Python 2
and Python 3, so it does not specify the Python version in its first
line.

For an example of the utility of this script: after running
gen_compile_commands.json on the latest kernel version, I was able to
use Vim + the YouCompleteMe pluging + clangd to automatically jump to
definitions and declarations. Obviously, cscope and ctags provide some
of this functionality; the advantage of supporting LibTooling is that it
opens the door to many other clang-based tools that understand the code
directly and do not rely on regular expressions and heuristics.

Tested: Built several recent kernel versions and ran the script against
them, testing tools like clangd (for editor/LSP support) and clang-check
(for static analysis). Also extracted some test .cmd files from a kernel
build and wrote a test script to check that the script behaved correctly
with all permutations of the --output and --directory flags.

Signed-off-by: Tom Roeder <tmroeder@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-19 23:41:36 +09:00
..
basic kbuild: simplify dependency generation for CONFIG_TRIM_UNUSED_KSYMS 2018-12-01 23:13:14 +09:00
coccinelle scripts: coccinelle: Correct warning message 2018-12-17 00:33:44 +09:00
dtc Merge branch 'all-dtbs' into dt/next 2018-10-04 14:16:15 -05:00
gcc-plugins stackleak: Allow runtime disabling of kernel stack erasing 2018-09-04 10:35:48 -07:00
gdb scripts/gdb/linux/tasks.py: fix get_thread_info 2018-01-19 10:09:41 -08:00
genksyms genksyms: remove symbol prefix support 2018-05-17 22:43:35 +09:00
kconfig kconfig: merge_config: avoid false positive matches from comment lines 2018-11-11 23:04:51 +09:00
ksymoops Fix dead URLs to ftp.kernel.org 2017-03-28 16:16:52 +02:00
mod kbuild: move modpost out of 'scripts' target 2018-12-01 23:09:34 +09:00
package kbuild: remove redundant 'set -e' from cmd_* defines 2018-12-01 23:13:14 +09:00
selinux staging: lustre: delete the filesystem from the tree. 2018-06-05 19:22:35 +02:00
tracing scripts: Add Python 3 support to tracing/draw_functrace.py 2018-07-29 11:08:38 +09:00
.gitignore kbuild: move bin2c back to scripts/ from scripts/basic/ 2018-07-18 01:18:05 +09:00
adjust_autoksyms.sh kbuild: remove CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX 2018-05-17 22:44:57 +09:00
asn1_compiler.c ASN.1: Remove unnecessary shadowed local variable 2018-10-29 00:19:41 +09:00
bin2c.c kbuild: move bin2c back to scripts/ from scripts/basic/ 2018-07-18 01:18:05 +09:00
bloat-o-meter syscalls/core, syscalls/x86: Clean up compat syscall stub naming convention 2018-04-09 16:47:28 +02:00
bootgraph.pl scripts: Switch to more portable Perl shebang 2017-05-14 11:20:44 +09:00
bpf_helpers_doc.py bpf: change eBPF helper doc parsing script to allow for smaller indent 2018-05-17 17:34:43 +02:00
cc-can-link.sh bpfilter: check compiler capability in Kconfig 2018-06-28 13:36:39 +09:00
check_extable.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
checkincludes.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
checkkconfigsymbols.py checkkconfigsymbols.py: support Kconfig's 'imply' statement 2017-02-03 11:49:06 +01:00
checkpatch.pl checkpatch: remove GCC_BINARY_CONSTANT warning 2018-10-31 08:54:13 -07:00
checkstack.pl scripts: Add ppc64le support for checkstack.pl 2018-07-02 23:54:28 +10:00
checksyscalls.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
checkversion.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
clang-version.sh kbuild: Add a space after ! to prevent parsing as file pattern 2018-08-22 23:21:40 +09:00
cleanfile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cleanpatch License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
coccicheck coccicheck: return proper error code on fail 2018-08-14 08:58:56 +09:00
config License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
conmakehash.c
const_structs.checkpatch
decode_stacktrace.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
decodecode scripts/decodecode: make it take multiline Code line 2018-01-31 17:18:34 -08:00
depmod.sh kbuild: modules_install: warn when missing System.map file 2018-09-09 09:14:07 +09:00
diffconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
documentation-file-ref-check scripts/documentation-file-ref-check: ignore sched-pelt false positive 2018-07-02 11:25:00 -06:00
export_report.pl scripts: Switch to more portable Perl shebang 2017-05-14 11:20:44 +09:00
extract_xc3028.pl MAINTAINERS & files: Canonize the e-mails I use at files 2018-05-04 06:21:06 -04:00
extract-cert.c
extract-ikconfig
extract-module-sig.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
extract-sys-certs.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
extract-vmlinux extract-vmlinux: Check for uncompressed image as fallback 2018-10-17 08:18:01 +02:00
faddr2line scripts/faddr2line: make the new code listing format optional 2018-06-05 09:04:37 -07:00
file-size.sh kbuild: Use ls(1) instead of stat(1) to obtain file size 2018-03-26 02:01:24 +09:00
find-unused-docs.sh scripts: Add a script to find unused documentation 2017-10-23 08:01:37 -06:00
gcc-goto.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gcc-ld License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gcc-plugin.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gcc-version.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gcc-x86_32-has-stack-protector.sh stack-protector: test compiler capability in Kconfig and drop AUTO mode 2018-06-08 18:56:00 +09:00
gcc-x86_64-has-stack-protector.sh stack-protector: Fix test with 32-bit userland and CONFIG_64BIT=y 2018-06-25 23:21:13 +09:00
gen_compile_commands.py scripts: add a tool to produce a compile_commands.json file 2018-12-19 23:41:36 +09:00
gen_ksymdeps.sh kbuild: simplify dependency generation for CONFIG_TRIM_UNUSED_KSYMS 2018-12-01 23:13:14 +09:00
get_dvb_firmware scripts: Switch to more portable Perl shebang 2017-05-14 11:20:44 +09:00
get_maintainer.pl get_maintainer: allow option --mpath <directory> to read all files in <directory> 2018-08-22 10:52:48 -07:00
gfp-translate
headerdep.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
headers_check.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
headers_install.sh kbuild: Improve portability of some sed invocations 2018-03-26 02:01:18 +09:00
headers.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
insert-sys-cert.c
kallsyms.c kallsyms: remove left-over Blackfin code 2018-09-10 22:54:33 +09:00
Kbuild.include kbuild: move .SECONDARY special target to Kbuild.include 2018-12-02 14:11:49 +09:00
Kconfig.include gcc-plugins: test plugin support in Kconfig and clean up Makefile 2018-06-11 09:16:22 +09:00
kernel-doc kernel-doc: fix declaration type determination 2018-10-18 12:20:35 -06:00
ld-version.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
leaking_addresses.pl leaking_addresses: check if file name contains address 2018-04-07 08:50:34 +10:00
Lindent License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
link-vmlinux.sh kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
Makefile kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile 2018-12-01 23:09:38 +09:00
Makefile.asm-generic kbuild: refactor Makefile.asm-generic 2018-12-17 00:33:14 +09:00
Makefile.build kbuild: handle part-of-module correctly for *.ll and *.symtypes 2018-12-17 00:33:43 +09:00
Makefile.clean kbuild: remove deprecated host-progs variable 2018-08-09 21:51:17 +09:00
Makefile.dtbinst DeviceTree for 4.15: 2017-11-14 18:25:40 -08:00
Makefile.extrawarn Kbuild updates for v4.20 (2nd) 2018-11-03 10:47:33 -07:00
Makefile.gcc-plugins kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile 2018-12-01 23:09:38 +09:00
Makefile.headersinst kbuild: remove a special handling for *.agh in Makefile.headersinst 2018-12-08 10:52:20 +09:00
Makefile.host kbuild: Rename HOST_LOADLIBES to KBUILD_HOSTLDLIBS 2018-07-18 01:18:05 +09:00
Makefile.kasan kasan: rework Kconfig settings 2018-02-06 18:32:47 -08:00
Makefile.kcov kcov: test compiler capability in Kconfig and correct dependency 2018-06-11 09:14:08 +09:00
Makefile.lib kbuild: remove redundant 'set -e' from filechk_offsets 2018-12-01 23:13:14 +09:00
Makefile.modbuiltin Kbuild: Makefile.modbuiltin: include auto.conf and tristate.conf mandatory 2018-08-03 00:47:00 +09:00
Makefile.modinst kbuild: remove duplicated comments about PHONY 2018-07-06 22:04:03 +09:00
Makefile.modpost kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
Makefile.modsign kbuild: remove duplicated comments about PHONY 2018-07-06 22:04:03 +09:00
Makefile.ubsan lib/ubsan: remove null-pointer checks 2018-08-10 20:19:58 -07:00
makelst License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
markup_oops.pl scripts: Switch to more portable Perl shebang 2017-05-14 11:20:44 +09:00
mkcompile_h Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
mkmakefile kbuild: simplify command line creation in scripts/mkmakefile 2018-10-04 22:56:02 +09:00
mksysmap
mkuboot.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
module-common.lds module: set .init_array alignment to 8 2017-03-13 09:40:28 -07:00
namespace.pl kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00
objdiff scripts: objdiff: Ignore debug info when comparing 2017-03-11 11:13:38 +09:00
parse-maintainers.pl parse-maintainers: add ability to specify filenames 2017-11-17 16:10:01 -08:00
patch-kernel License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pnmtologo.c
profile2linkerlist.pl License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
prune-kernel License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
recordmcount.c scripts: Fixed printf format mismatch 2018-05-29 22:04:12 +09:00
recordmcount.h scripts: Fixed printf format mismatch 2018-05-29 22:04:12 +09:00
recordmcount.pl nds32/ftrace: Add RECORD_MCOUNT support 2018-09-04 14:45:18 +08:00
setlocalversion scripts/setlocalversion: Improve -dirty check with git-status --no-optional-locks 2018-11-21 23:57:33 +09:00
show_delta
sign-file.c sign-file: fix build error in sign-file.c with libressl 2017-02-10 12:43:47 +11:00
sortextable.c
sortextable.h
spdxcheck.py scripts: add Python 3 compatibility to spdxcheck.py 2018-08-17 16:20:27 -07:00
spelling.txt treewide: correct "differenciate" and "instanciate" typos 2018-08-23 18:48:43 -07:00
sphinx-pre-install docs-rst: don't require adjustbox anymore 2017-09-08 10:02:55 -06:00
split-man.pl MAINTAINERS & files: Canonize the e-mails I use at files 2018-05-04 06:21:06 -04:00
stackdelta License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
stackusage License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
subarch.include selftests: add headers_install to lib.mk 2018-09-05 08:12:09 -06:00
tags.sh scripts/tags.sh: add DECLARE_HASHTABLE() 2018-10-26 16:25:18 -07:00
unifdef.c
ver_linux ver_linux: Do not check for ver_linux pattern in version function 2018-07-07 17:44:52 +02:00
xen-hypercalls.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
xz_wrap.sh