abi-compliance-checker and abi-dumper to track API/ABI

[Andrey Ponomarenko <aponomarenko@rosalab.ru>]

Hi,

There is a new simple way to track changes in API/ABI of system 
libraries using a new ABI dumper [1] tool. Just compile two library 
versions with -g additional option (to contain DWARF debug info) or take 
them from the appropriate debug packages and create ABI dumps of both:

  abi-dumper OLD.so -o ABI-0.dump -lver 0
  abi-dumper NEW.so -o ABI-1.dump -lver 1

Then compare these ABI dumps by the ACC [2] tool:

  abi-compliance-checker -l NAME -old ABI-0.dump -new ABI-1.dump

So it is no need to create any input XML descriptors and compile header 
files of a library anymore.

However, this approach has some drawbacks. Perhaps the main drawback is 
the inability to perform some compatibility checks. For example, there 
is no possibility to check for changes in the values of the constants 
(defines as well as const global data), since their values are inlined 
at compile time, and not presented in the debug information of the 
binary ELF-object. In general, there can be checked about 98% of all 
compatibility rules.

Another disadvantage is the long time required to analyse large objects 
bigger than 50 mb. But one can use the dwz utility to compress input 
debug-info.

Enjoy!

[1] https://github.com/lvc/abi-dumper
[2] https://github.com/lvc/abi-compliance-checker

--
Andrey Ponomarenko, ROSA Lab.