header-abi-dumper is a tool to dump the abi of a source file. The abi dumped belonging to a source file. The abi dumped, maybe be filtered to include only the abi information contained in public headers by specifying -I with the invocation of header-abi-dumper.
header-abi-dumper -o <source_file> -I -I .. -- For options : header-abi-dumper --help
header-abi-linker is a tool to link abi dumps produced by header-abi-dumper. This tool combines all the abi information present in the dump files passed to it.
header-abi-linker -o ... -so -v For options : header-abi-linker --help
header-abi-diff is a tool which compares two header abi dumps produced by header-abi-dumper. It produces a report outlining all the differences in the abi's exposed by the two dumps.
0: Compatible 1: Changes to APIs unreferenced by symbols in the .dynsym table 4: Compatible Extension 8: Incompatible 16: Elf Incompatible : some symbols in the .dynsym table, not exported by public headers, were removed.
header-abi-diff -old -new -o For options : header-abi-diff --help
utils/create_reference_dumps.py may be used to create reference abi dumps. For options, refer to utils/create_reference_dumps.py --help.
As an example, these steps could be followed to create reference abi-dumps :
$ cd $(ANDROID_BUILD_TOP); lunch aosp_arm64; make -j64 $ python3 utils/create_reference_dumps.py --vndk-list vndk_list -ref-dump-dir
$(ANDROID_BUILD_TOP)/prebuilts/abi-dumps/vndk --version current
--vndk_list : file containing a list of the libraries whose reference dumps are to be created, seperated by \n. For eg: vndk_list: libtinyxml2 libziparchive libc++ --version: This is the version of the vndk being built. This will create corresponding .lsdump files at $(ANDROID_BUILD_TOP)/prebuilts/abi-dumps/vndk/arm(64)/current/source-based
gzip the reference dumps produced : $ cd $(ANDROID_BUILD_TOP)/prebuilts/abi-dumps/vndk/arm(64)/current/source-based; $ gzip *.lsdump;
The same procedure should also be followed for ll-ndk libraries, listing them in a seperate file and running create_reference_dumps.py with -ref-dump-dir set to $(ANDROID_BUILD_TOP)/prebuilts/abi-dumps/ndk.
On subsequent arm based builds, header-abi-diff will report warnings on abi-breakages and changes to exported apis.