Cross translational unit analysis in codechecker

Clang Frontend
1

Hi,
can anyone tell how to use codechecker https://github.com/Ericsson/codechecker with cross translational unit analysis flag for analysis across translational unit ?

Thanks,
Siddharth

2

Hi Siddharth,

since the CTU functionality is not yet part of the mainline clang (review ongoing), you will need to clone our patched version of clang5

https://github.com/Ericsson/clang

(ctu-clang5 branch)

please use the following llvm commit revision to compile clang:

Branch ctu-clang5 → LLVM commit 657c31173ea30090583e40c7a9204561d9c2d8c4

when you compiled clang successfully you should have a “clang-func-mapping” binary in the <build_dir>/bin directory.

Then create a codechecker package as described here

https://github.com/Ericsson/codechecker#linux

Add <LLVM_BUILD_DIR>/bin to your path e.g.: export PATH=<LLVM_BUILD_DIR>/bin:$PATH

so CodeChecker will find this new CTU patched version of clang.

If all went fine you start CodeChecker analyze –help and it will print:

cross translation unit analysis arguments:

These arguments are only available if the Clang Static Analyzer supports

Cross-TU analysis. By default, no CTU analysis is ran when 'CodeChecker

analyze’ is called.

–ctu, --ctu-all Perform Cross Translation Unit (CTU) analysis, both

‘collect’ and ‘analyze’ phases. In this mode, the

extra files created by ‘collect’ are cleaned up after

the analysis.

–ctu-collect Perform the first, ‘collect’ phase of Cross-TU

analysis. This phase generates extra files needed by

CTU analysis, and puts them into '<OUTPUT_DIR>/ctu-

dir’. NOTE: If this argument is present, CodeChecker

will NOT execute the analyzers!

–ctu-analyze Perform the second, ‘analyze’ phase of Cross-TU

analysis, using already available extra files in

‘<OUTPUT_DIR>/ctu-dir’. (These files will not be

cleaned up in this mode.)

–ctu-on-the-fly If specified, the ‘collect’ phase will not create the

extra AST dumps, but rather analysis will be ran with

an in-memory recompilation of the source files.

Then you can say to analyze your code:

CodeChecker log -b “make” -o compilation.json

CodeChecker analyze compilation.json –ctu-all -o reports

then print the reports

CodeChecker parse ./reports

(For more howto see: https://github.com/Ericsson/codechecker/blob/master/docs/usage.md)

I hope this helps.

Regards,

Daniel

3

Thanks Daniel for the info.
Siddharth