1 Smatch 2 3 0. Introduction 4 1. Building Smatch 5 2. Using Smatch 6 3. Smatch vs Sparse 7 8 Section 0: Introduction 9 10 The Smatch mailing list is <smatch@vger.kernel.org>. 11 12 Section 1: Building Smatch 13 --------------------------- 14 15 Smatch requires sqlite3. It requires the binaries and the C, Perl and 16 Python libraries for sqlite3. 17 18 apt-get install sqlite3 libsqlite3-dev libdbd-sqlite3-perl 19 20 Smatch is easy to build. Just type `make`. There isn't an install process 21 right now so just run it from the build directory. 22 23 24 Section 2: Using Smatch 25 ------------------------ 26 27 Smatch can be used with a cross function database. It's not mandatory to 28 build the database but it's a useful thing to do. Building the database 29 for the kernel takes 2-3 hours on my computer. For the kernel you build 30 the database with: 31 32 cd ~/path/to/kernel_dir 33 ~/path/to/smatch_dir/smatch_scripts/build_kernel_data.sh 34 35 For projects other than the kernel you run Smatch with the options 36 "--call-tree --info --param-mapper --spammy" and finish building the 37 database by running the script: 38 39 ~/progs/smatch/devel/smatch_data/db/create_db.sh 40 41 Each time you rebuild the cross function database it becomes more accurate. I 42 normally rebuild the database every morning. 43 44 If you are running Smatch over the whole kernel you can use the following 45 command: 46 47 ~/progs/smatch/devel/smatch_scripts/test_kernel.sh 48 49 The test_kernel.sh script will create a .c.smatch file for every file it tests 50 and a combined smatch_warns.txt file with all the warnings. 51 52 If you are running Smatch just over one kernel file: 53 54 ~/progs/smatch/devel/smatch_scripts/kchecker drivers/whatever/file.c 55 56 You can also build a directory like this: 57 58 ~/progs/smatch/devel/smatch_scripts/kchecker drivers/whatever/ 59 60 The kchecker script prints its warnings to stdout. 61 62 The above scripts will ensure that any ARCH or CROSS_COMPILE environment 63 variables are passed to kernel build system - thus allowing for the use of 64 Smatch with kernels that are normally built with cross-compilers. 65 66 If you are building something else (which is not the Linux kernel) then use 67 something like: 68 69 make CHECK="~/progs/smatch/devel/smatch --full-path" \ 70 CC=~/progs/smatch/devel/smatch/cgcc | tee smatch_warns.txt 71 72 The makefile has to let people set the CC with an environment variable for that 73 to work, of course. 74 75 76 Section 3: Smatch vs Sparse 77 ---------------------------- 78 79 Smatch uses Sparse as a C parser. I have made a few hacks to Sparse so I 80 have to distribute the two together. Sparse is released under the MIT license 81 and Smatch is GPLv2+. If you make changes to Sparse please send those to the 82 Sparse mailing list linux-sparse@vger.kernel.org and I will pick them up from 83 there. Partly I do that for licensing reasons because I don't want to pull GPL 84 changes into the Sparse code I re-distribute. 85