Better, stronger, faster ... there is zapcc

Hi folks,


Today is test's day ! After the test of the static code analyser PVS-STUDIO, this time it will be a new C/C++  compiler on the market, zapcc from the young company Ceemple Software which is based on a modified version of LLVM/clang coming with an innovative caching system. It is available on Mac OS X, Linux and Windows. It works with any unix project based with cmake, autotools.

1/ Projects to test

To have some interesting numbers, I will try with some software important enough which needs several minutes of compilation, LMMS, the popular professional music production platform ... The tests will be conducted with unmodified clang provided by the system and zapcc, under Linux Mint, hardware is a i5-5200U CPU and 8GB of RAM.

Let's start with clang

This is the output with make's 5 jobs

Now ... zapcc which I just increased the default memory cache in the zapccs.config file from 1200 to 2000. Apart of this, we can also add which files we do not wish to be cached.

 The compilers executables are respectively zapcc and zapcc++ but we can see their clang "inheritance" through the following output ...

As you can see, there is a noticeable time decrease.
What if I try with another source code, opencv for instance to see if there is again a visible decrease as opencv takes longer to build than lmms.

Here, the output with clang ....

zapcc ...

As you can see, the delta is again pretty important ! Good job !


2/ Conclusion
 
Zapcc would be valuable for projects like Qt4/5 which usually take several hours to complete the compilation of all the components. In a professional perspective, the value of zappc is perceptible, usually C++ projects mean important sizes, thus by lessening the time spent on the build we can reallocate this time for other ressources ... But due to the caching, you have to keep in mind there is a logical and unavoidable memory usage increase, thus the settings of this part ought to be balanced regarding the target hardware ...

As zapcc is based on clang/LLVM, it could be possibly ported to FreeBSD as this platform gains more and more popularity in the professional world, it might be worthy to consider this possibility.

Static code analysis

Hi folks,

In the software development process, the static code analysis is an important step and I am personally convinced by its utility (although knowing it is a difficult science) even when I contribute to open source projects. Usually I use either the popular clang scan-build command line tool and/or the excellent online solution Scan Coverity. Sometimes cppcheck as well.

But today, I m going to present another set of tools, PVS-Studio from viva64.com which has originally a Windows version with an integration with Visual Studio but appears to have been working on a Linux version as well which I will be focusing with. It works with my main languages C / C++ and in addition with .NET/C#

With the Linux version 6.09.18904, we have the choice between a simple tgz archive, a RedHat family rpm and a Debian family package. I did all my tests under Linux Mint 18 and the GCC suite.

1/ Choice of a project

Let's try with one well known open source project, the PHP programming language, which is basically uses the not less famous trio configure/make/make install ... Thus after setting our preferences via the configure script, we can now use pvs-studio on top of the make build system.

pvs-studio-analyser trace -- make

pvs-studio-analyser analyse -o php.plog -l <path to licence file> -j<number of parallel jobs>

Which produces an output file in the PLOG format which can be converted to xml, task files with the provided plog-converter command line. Fortunately as the process can take a certain time, it is possible to parallelize via the j flag.

2/ Outcomes

The output gotten, here in XML, contains well known useful good practices like about realloc http://www.viva64.com/en/w/V701/

or the return check for strcmp http://www.viva64.com/en/w/V526/

 some rules specific to C++ obviously like implementing the copy constructor but not the assignment operator http://www.viva64.com/en/w/V690/
 or the uselessness of checking null from a raw pointer after a new operator use
http://www.viva64.com/en/w/V668/
 ... and many more, there is a list available here.

PVS-studio was successfully exploited by another user in another open source project I pushed a pull request to recently, Unvanquished

3/ Conclusion

One of the few criticisms I may have is it seems not able to catch resource / memory leaks even very simple cases, whether it is C or C++.  Another proof that using more than one analyser is mandatory.

Maybe a Mac OS version with an integration with Xcode would be a plus in the future, although I perfectly understand the cost of development but ... might be worthy.