[LU-871] clang: minor code cleanups

• Type: Technical task
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.2.0
• Affects Version/s: Lustre 2.2.0
• Labels: clang
• Environment: FC13 running clang-analyzer-2.8-10.fc13.x86_64
• Assignee: Andreas Dilger
• Reporter: Andreas Dilger

Description

Tracking bug for warnings produced by the clang-analyzer static code analysis tool.

The first one is a trivial printk() format warning due to the use of "%Lu" for LPU64, and other places in the code. The "%L" format specifier is a GCCism that is deprecated in favor of "%ll" from C99.

Issue Links

• is related to: LU-2675 clang: code cleanups for sparse static analyzer
• Trackbacks: Changelog 2.2 version 2.2.0 Support for networks: o2iblnd OFED 1.5.4 Server support for kernels: 2.6.32220.4.2.el6 (RHEL6) Client support for unpatched kernels: 2.6.18274.18.1.el5 (RHEL5) 2.6.32220.4.2.el6 (RHEL6) 2.6.32.360....
• Trackbacks: Project Ideas Information for Developers Working on Lustre will quickly introduce a developer to the always interesting and impressive world of HPC, where the systems are the largest in the world,...

Comments

[Andreas Dilger]

Karsten, thanks for submitting these patches. Sorry I didn't reply to this when it was first posted, as it slipped off my radar. Could you please submit these patches to our Gerrit (code review) git repository? Please see http://wiki.whamcloud.com/display/PUB/Using+Gerrit for details.

This will allow us to review, test, and land the patches to Lustre, and not have them sitting in an attachment here.

[Karsten Weiss]

FWIW I've compiled Lustre 2.1.54 patchless client on CentOS 6.2 with Clang's static analyzer (LLVM 3.0).

I decided to disable the static analyzer check "core.NullDereference" because it detects lots of bugs (521). However, based on a first short glance most of them are dubious because the analyzer seems to get confused by Lustre's LASSERT(). (And including all of these 521 bugs would make the tarball larger than the Jira upload file limit.)

Here's the bug summary:

Bug Type	Quantity
All Bugs	270
API
Argument with 'nonnull' attribute passed null	16
Dead code
Idempotent operation	30
Dead store
Dead assignment	120
Dead increment	6
Dead initialization	20
Logic error
Assigned value is garbage or undefined	12
Called function pointer is null (null dereference)	31
Division by zero	4
Function call argument is an uninitialized value	14
Garbage return value	6
Result of operation is garbage or undefined	8
Unix API
Undefined allocation of 0 bytes	3

Check out the annotated source in the attached tarball with a web browser.

This is how the source was compiled:

touch META
sh autogen.sh
scan-build ./configure --disable-server \
--with-linux=/usr/src/kernels/2.6.32-220.2.1.el6.x86_64 \
--with-linux-obj=/lib/modules/2.6.32-220.2.1.el6.x86_64/build/ \
--with-downstream-release=wc1
mkdir ./lustre-2.1.54-scan-build
scan-build -o ./lustre-2.1.54-scan-build/ \
-disable-checker core.NullDereference \
make -j 24

[Build Master (Inactive)]

Integrated in lustre-master » i686,server,el5,ofa #378
LU-871 build: change %L printk format to %ll (Revision 3684de257a7e8932936a27d0fdb3ecb39653e624)

Result = SUCCESS
Oleg Drokin : 3684de257a7e8932936a27d0fdb3ecb39653e624
Files :

• lustre/utils/gss/lgss_utils.c
• lustre/llite/file.c
• lustre/utils/gss/lgss_keyring.c
• lustre/tests/checkstat.c
• lustre/fid/lproc_fid.c
• lustre/liblustre/super.c
• libcfs/include/libcfs/posix/posix-wordsize.h
• lustre/tests/truncate.c
• lnet/utils/routerstat.c
• lustre/llite/rw.c
• lustre/include/lustre_debug.h
• libcfs/include/libcfs/linux/kp30.h

[Build Master (Inactive)]

Integrated in lustre-master » i686,server,el6,inkernel #378
LU-871 build: change %L printk format to %ll (Revision 3684de257a7e8932936a27d0fdb3ecb39653e624)

Result = SUCCESS
Oleg Drokin : 3684de257a7e8932936a27d0fdb3ecb39653e624
Files :

• lustre/llite/rw.c
• libcfs/include/libcfs/linux/kp30.h
• lustre/utils/gss/lgss_utils.c
• lustre/fid/lproc_fid.c
• lustre/tests/checkstat.c
• lustre/liblustre/super.c
• lustre/tests/truncate.c
• lustre/utils/gss/lgss_keyring.c
• lustre/llite/file.c
• lustre/include/lustre_debug.h
• lnet/utils/routerstat.c
• libcfs/include/libcfs/posix/posix-wordsize.h