scan-build ========== A package designed to wrap a build so that all calls to gcc/clang are intercepted and logged into a [compilation database][1] and/or piped to the clang static analyzer. Includes intercept-build tool, which logs the build, as well as scan-build tool, which logs the build and runs the clang static analyzer on it. Portability ----------- Should be working on UNIX operating systems. - It has been tested on FreeBSD, GNU/Linux and OS X. - Prepared to work on windows, but need help to make it. Prerequisites ------------- 1. **python** interpreter (version 3.6 or later). How to use ---------- To run the Clang static analyzer against a project goes like this: $ scan-build To generate a compilation database file goes like this: $ intercept-build To run the Clang static analyzer against a project with compilation database goes like this: $ analyze-build Use `--help` to know more about the commands. How to use the experimental Cross Translation Unit analysis ----------------------------------------------------------- To run the CTU analysis, a compilation database file has to be created: $ intercept-build To run the Clang Static Analyzer against a compilation database with CTU analysis enabled, execute: $ analyze-build --ctu For CTU analysis an additional (external definition) collection-phase is required. For debugging purposes, it is possible to separately execute the collection and the analysis phase. By doing this, the intermediate files used for the analysis are kept on the disk in `./ctu-dir`. # Collect and store the data required by the CTU analysis $ analyze-build --ctu-collect-only # Analyze using the previously collected data $ analyze-build --ctu-analyze-only Use `--help` to get more information about the commands. Limitations ----------- Generally speaking, the `intercept-build` and `analyze-build` tools together does the same job as `scan-build` does. So, you can expect the same output from this line as simple `scan-build` would do: $ intercept-build && analyze-build The major difference is how and when the analyzer is run. The `scan-build` tool has three distinct model to run the analyzer: 1. Use compiler wrappers to make actions. The compiler wrappers does run the real compiler and the analyzer. This is the default behaviour, can be enforced with `--override-compiler` flag. 2. Use special library to intercept compiler calls during the build process. The analyzer run against each modules after the build finished. Use `--intercept-first` flag to get this model. 3. Use compiler wrappers to intercept compiler calls during the build process. The analyzer run against each modules after the build finished. Use `--intercept-first` and `--override-compiler` flags together to get this model. The 1. and 3. are using compiler wrappers, which works only if the build process respects the `CC` and `CXX` environment variables. (Some build process can override these variable as command line parameter only. This case you need to pass the compiler wrappers manually. eg.: `intercept-build --override-compiler make CC=intercept-cc CXX=intercept-c++ all` where the original build command would have been `make all` only.) The 1. runs the analyzer right after the real compilation. So, if the build process removes removes intermediate modules (generated sources) the analyzer output still kept. The 2. and 3. generate the compilation database first, and filters out those modules which are not exists. So, it's suitable for incremental analysis during the development. The 2. mode is available only on FreeBSD and Linux. Where library preload is available from the dynamic loader. Not supported on OS X (unless System Integrity Protection feature is turned off). `intercept-build` command uses only the 2. and 3. mode to generate the compilation database. `analyze-build` does only run the analyzer against the captured compiler calls. Known problems -------------- Because it uses `LD_PRELOAD` or `DYLD_INSERT_LIBRARIES` environment variables, it does not append to it, but overrides it. So builds which are using these variables might not work. (I don't know any build tool which does that, but please let me know if you do.) Problem reports --------------- If you find a bug in this documentation or elsewhere in the program or would like to propose an improvement, please use the project's [issue tracker][3]. Please describing the bug and where you found it. If you have a suggestion how to fix it, include that as well. Patches are also welcome. License ------- The project is licensed under Apache-2.0 with LLVM exceptions. See LICENSE.TXT for details. [1]: http://clang.llvm.org/docs/JSONCompilationDatabase.html [2]: https://pypi.python.org/pypi/scan-build [3]: https://llvm.org/bugs/enter_bug.cgi?product=clang