abipkgdiff(1) — Linux manual page

NAME | INVOCATION | ENVIRONMENT | OPTIONS | RETURN VALUE | AUTHOR | COPYRIGHT | COLOPHON

ABIPKGDIFF(1)                  Libabigail                  ABIPKGDIFF(1)

NAME         top

       abipkgdiff - compare ABIs of ELF files in software packages

       abipkgdiff compares the Application Binary Interfaces (ABI) of
       the ELF binaries contained in two software packages.  The
       software package formats currently supported are Deb, RPM, tar
       archives (either compressed or not) and plain directories that
       contain binaries.

       For a comprehensive ABI change report that includes changes about
       function and variable sub-types, the two input packages must be
       accompanied with their debug information packages that contain
       debug information either in DWARF, CTF or in BTF formats.  Please
       note however that some packages contain binaries that embed the
       debug information directly in a section of said binaries.  In
       those cases, obviously, no separate debug information package is
       needed as the tool will find the debug information inside the
       binaries.

       By default, abipkgdiff uses debug information in DWARF format, if
       present, otherwise it compares binaries interfaces using debug
       information in CTF or in BTF formats, if present. Finally, if no
       debug info in these formats is found, it only considers ELF
       symbols and report about their addition or removal.

       This tool uses the libabigail library to analyze the binary as
       well as its associated debug information.  Here is its general
       mode of operation.

       When instructed to do so, a binary and its associated debug
       information is read and analyzed.  To that effect, libabigail
       analyzes by default the descriptions of the types reachable by
       the interfaces (functions and variables) that are visible outside
       of their translation unit.  Once that analysis is done, an
       Application Binary Interface Corpus is constructed by only
       considering the subset of types reachable from interfaces
       associated to ELF symbols that are defined and exported by the
       binary.  It's that final ABI corpus which libabigail considers as
       representing the ABI of the analyzed binary.

       Libabigail then has capabilities to generate textual
       representations of ABI Corpora, compare them, analyze their
       changes and report about them.

INVOCATION         top

          abipkgdiff [option] <package1> <package2>

       package1 and package2 are the packages that contain the binaries
       to be compared.

ENVIRONMENT         top

       abipkgdiff loads two default suppression specifications files,
       merges their content and use it to filter out ABI change reports
       that might be considered as false positives to users.

       • Default system-wide suppression specification file

         It's located by the optional environment variable
         LIBABIGAIL_DEFAULT_SYSTEM_SUPPRESSION_FILE.  If that
         environment variable is not set, then abipkgdiff tries to load
         the suppression file
         $libdir/libabigail/libabigail-default.abignore.  If that file
         is not present, then no default system-wide suppression
         specification file is loaded.

       • Default user suppression specification file.

         It's located by the optional environment
         LIBABIGAIL_DEFAULT_USER_SUPPRESSION_FILE.  If that environment
         variable is not set, then abipkgdiff tries to load the
         suppression file $HOME/.abignore.  If that file is not present,
         then no default user suppression specification is loaded.

       In addition to those default suppression specification files,
       abipkgdiff will also look inside the packages being compared and
       if it sees a file that ends with the extension .abignore, then it
       will consider it as a suppression specification and it will
       combine it to the default suppression specification that might be
       already loaded.

       The user might as well use the --suppressions option (that is
       documented further below) to provide a suppression specification.

OPTIONS         top

--help | -h

            Display a short help about the command and exit.

          • --version | -v

            Display the version of the program and exit.

          • --debug-info-pkg1 | --d1 <path>

            For cases where the debug information for package1 is split
            out into a separate file, tells abipkgdiff where to find
            that separate debug information package.

            Note that the debug info for package1 can have been split
            into several different debug info packages.  In that case,
            several instances of this options can be provided, along
            with those several different debug info packages.

          • --debug-info-pkg2 | --d2 <path>

            For cases where the debug information for package2 is split
            out into a separate file, tells abipkgdiff where to find
            that separate debug information package.

            Note that the debug info for package2 can have been split
            into several different debug info packages.  In that case,
            several instances of this options can be provided, along
            with those several different debug info packages.

          • --devel-pkg1 | --devel1 <path>

            Specifies where to find the Development Package associated
            with the first package to be compared.  That Development
            Package at path should at least contain header files in
            which public types exposed by the libraries (of the first
            package to be compared) are defined.  When this option is
            provided, the tool filters out reports about ABI changes to
            types that are NOT defined in these header files.

          • --devel-pkg2 | --devel2 <path>

            Specifies where to find the Development Package associated
            with the second package to be compared.  That Development
            Package at path should at least contains header files in
            which public types exposed by the libraries (of the second
            package to be compared) are defined.  When this option is
            provided, the tool filters out reports about ABI changes to
            types that are NOT defined in these header files.

          • --drop-private-types

            This option is to be used with the --devel-pkg1 and
            --devel-pkg2 options.  With this option, types that are NOT
            defined in the headers are entirely dropped from the
            internal representation build by Libabigail to represent the
            ABI.  They thus don't have to be filtered out from the final
            ABI change report because they are not even present in
            Libabigail's representation.

            Without this option however, those private types are kept in
            the internal representation and later filtered out from the
            report.

            This options thus potentially makes Libabigail consume less
            memory.  It's meant to be mainly used to optimize the memory
            consumption of the tool on binaries with a lot of publicly
            defined and exported types.

          • --dso-only

            Compare ELF files that are shared libraries, only.  Do not
            compare executable files, for instance.

          • --private-dso

            By default, abipkgdiff does not compare DSOs that are
            private to the RPM package.  A private DSO is a DSO which
            SONAME is NOT advertised in the "provides" property of the
            RPM.

            This option instructs abipkgdiff to also compare DSOs that
            are NOT advertised in the "provides" property of the RPM.

            Please note that the fact that (by default) abipkgdiff skips
            private DSO is a feature that is available only for RPMs, at
            the moment.  We would happily accept patches adding that
            feature for other package formats.

          • --leaf-changes-only|-l only show leaf changes, so don't show
            impact analysis report.  This option implies --redundant

            The typical output of abipkgdiff and abidiff when comparing
            two binaries, that we shall call full impact report, looks
            like this

                $ abidiff libtest-v0.so libtest-v1.so
                Functions changes summary: 0 Removed, 1 Changed, 0 Added function
                Variables changes summary: 0 Removed, 0 Changed, 0 Added variable

                1 function with some indirect sub-type change:

                  [C]'function void fn(C&)' at test-v1.cc:13:1 has some indirect sub-type changes:
                    parameter 1 of type 'C&' has sub-type changes:
                      in referenced type 'struct C' at test-v1.cc:7:1:
                        type size hasn't changed
                        1 data member change:
                         type of 'leaf* C::m0' changed:
                           in pointed to type 'struct leaf' at test-v1.cc:1:1:
                             type size changed from 32 to 64 bits
                             1 data member insertion:
                               'char leaf::m1', at offset 32 (in bits) at test-v1.cc:4:1

                $

            So in that example the report emits information about how
            the data member insertion change of "struct leaf" is
            reachable from function "void fn(C&)".  In other words, the
            report not only shows the data member change on "struct
            leaf", but it also shows the impact of that change on the
            function "void fn(C&)".

            In abidiff (and abipkgdiff) parlance, the change on "struct
            leaf" is called a leaf change.  So the --leaf-changes-only
            --impacted-interfaces options show, well, only the leaf
            change.  And it goes like this:

                $ abidiff -l libtest-v0.so libtest-v1.so
                'struct leaf' changed:
                  type size changed from 32 to 64 bits
                  1 data member insertion:
                    'char leaf::m1', at offset 32 (in bits) at test-v1.cc:4:1

                  one impacted interface:
                    function void fn(C&)
                $

            Note how the report ends up by showing the list of
            interfaces impacted by the leaf change.  That's the effect
            of the additional --impacted-interfaces option.

            Now if you don't want to see that list of impacted
            interfaces, then you can just avoid using the
            --impacted-interface option.  You can learn about that
            option below, in any case.

            Please note that when comparing two Linux Kernel packages,
            it's this leaf changes report that is emitted, by default.
            The normal so-called full impact report can be emitted with
            the option --full-impact which is documented later below.

          • --impacted-interfaces

            When showing leaf changes, this option instructs abipkgdiff
            to show the list of impacted interfaces.  This option is
            thus to be used in addition to the --leaf-changes-only
            option, or, when comparing two Linux Kernel packages.
            Otherwise, it's simply ignored.

          • --full-impact|-f

            When comparing two Linux Kernel packages, this function
            instructs abipkgdiff to emit the so-called full impact
            report, which is the default report kind emitted by the
            abidiff tool:

                $ abidiff libtest-v0.so libtest-v1.so
                Functions changes summary: 0 Removed, 1 Changed, 0 Added function
                Variables changes summary: 0 Removed, 0 Changed, 0 Added variable

                1 function with some indirect sub-type change:

                  [C]'function void fn(C&)' at test-v1.cc:13:1 has some indirect sub-type changes:
                    parameter 1 of type 'C&' has sub-type changes:
                      in referenced type 'struct C' at test-v1.cc:7:1:
                        type size hasn't changed
                        1 data member change:
                         type of 'leaf* C::m0' changed:
                           in pointed to type 'struct leaf' at test-v1.cc:1:1:
                             type size changed from 32 to 64 bits
                             1 data member insertion:
                               'char leaf::m1', at offset 32 (in bits) at test-v1.cc:4:1

                $

          • --non-reachable-types|-t

            Analyze and emit change reports for all the types of the
            binary, including those that are not reachable from global
            functions and variables.

            This option might incur some serious performance degradation
            as the number of types analyzed can be huge.  However, if
            paired with the --devel-pkg{1,2} options, the additional
            non-reachable types analyzed are restricted to those defined
            in the public headers files carried by the referenced
            development packages, thus hopefully making the performance
            hit acceptable.

            Also, using this option alongside suppression specifications
            (by also using the --suppressions option) might help keep
            the number of analyzed types (and the potential performance
            degradation) in control.

            Note that without this option, only types that are reachable
            from global functions and variables are analyzed, so the
            tool detects and reports changes on these reachable types
            only.

          • --exported-interfaces-only

            By default, when looking at the debug information
            accompanying a binary, this tool analyzes the descriptions
            of the types reachable by the interfaces (functions and
            variables) that are visible outside of their translation
            unit.  Once that analysis is done, an ABI corpus is
            constructed by only considering the subset of types
            reachable from interfaces associated to ELF symbols that are
            defined and exported by the binary.  It's those final ABI
            Corpora that are compared by this tool.

            The problem with that approach however is that analyzing all
            the interfaces that are visible from outside their
            translation unit can amount to a lot of data, especially
            when those binaries are applications, as opposed to shared
            libraries.  One example of such applications is the Linux
            Kernel.  Analyzing massive ABI corpora like these can be
            extremely slow.

            To mitigate that performance issue, this option allows
            libabigail to only analyze types that are reachable from
            interfaces associated with defined and exported ELF symbols.

            Note that this option is turned on by default when analyzing
            the Linux Kernel.  Otherwise, it's turned off by default.

          • --allow-non-exported-interfaces

            When looking at the debug information accompanying a binary,
            this tool analyzes the descriptions of the types reachable
            by the interfaces (functions and variables) that are visible
            outside of their translation unit.  Once that analysis is
            done, an ABI corpus is constructed by only considering the
            subset of types reachable from interfaces associated to ELF
            symbols that are defined and exported by the binary.  It's
            those final ABI Corpora that are compared by this tool.

            The problem with that approach however is that analyzing all
            the interfaces that are visible from outside their
            translation unit can amount to a lot of data, especially
            when those binaries are applications, as opposed to shared
            libraries.  One example of such applications is the Linux
            Kernel.  Analyzing massive ABI Corpora like these can be
            extremely slow.

            In the presence of an "average sized" binary however one can
            afford having libabigail analyze all interfaces that are
            visible outside of their translation unit, using this
            option.

            Note that this option is turned on by default, unless we are
            in the presence of the Linux Kernel.

          • --redundant
              In the diff reports, do display redundant changes.  A
              redundant change is a change that has been displayed
              elsewhere in a given report.

          • --harmless

            In the diff report, display only the harmless changes.  By
            default, the harmless changes are filtered out of the diff
            report keep the clutter to a minimum and have a greater
            chance to spot real ABI issues.

          • --no-linkage-name

            In the resulting report, do not display the linkage names of
            the added, removed, or changed functions or variables.

          • --no-added-syms

            Do not show the list of functions, variables, or any symbol
            that was added.

          • --no-added-binaries

            Do not show the list of binaries that got added to the
            second package.

            Please note that the presence of such added binaries is not
            considered like an ABI change by this tool; as such, it
            doesn't have any impact on the exit code of the tool.  It
            does only have an informational value.  Removed binaries
            are, however, considered as an ABI change.

          • --no-abignore

            Do not search the package for the presence of suppression
            files.

          • --no-parallel

            By default, abipkgdiff will use all the processors it has
            available to execute concurrently.  This option tells it not
            to extract packages or run comparisons in parallel.

          • --no-default-suppression

            Do not load the default suppression specification files.

          • --suppressions | --suppr <path-to-suppressions>

            Use a suppression specification file located at
            path-to-suppressions.  Note that this option can appear
            multiple times on the command line.  In that case, all of
            the suppression specification files are taken into account.

            Please note that, by default, if this option is not
            provided, then the default suppression specification files
            are loaded .

          • --linux-kernel-abi-whitelist | -w <path-to-whitelist>

            When comparing two Linux kernel RPM packages, this option
            points to the white list of names of ELF symbols of
            functions and variables that must be compared for ABI
            changes.  That white list is called a "Linux kernel ABI
            white list".

            Any other function or variable which ELF symbol are not
            present in that white list will not be considered by the ABI
            comparison process.

            If this option is not provided -- thus if no white list is
            provided -- then the ABI of all publicly defined and
            exported functions and global variables by the Linux Kernel
            binaries are compared.

            Please note that if a white list package is given in
            parameter, this option handles it just fine, like if the
            --wp option was used.

          • --wp <path-to-whitelist-package>

            When comparing two Linux kernel RPM packages, this option
            points an RPM package containining several white lists of
            names of ELF symbols of functions and variables that must be
            compared for ABI changes.  Those white lists are called
            "Linux kernel ABI white lists".

            From the content of that white list package, this program
            then chooses the appropriate Linux kernel ABI white list to
            consider when comparing the ABI of Linux kernel binaries
            contained in the Linux kernel packages provided on the
            command line.

            That choosen Linux kernel ABI white list contains the list
            of names of ELF symbols of functions and variables that must
            be compared for ABI changes.

            Any other function or variable which ELF symbol are not
            present in that white list will not be considered by the ABI
            comparison process.

            Note that this option can be provided twice (not mor than
            twice), specifying one white list package for each Linux
            Kernel package that is provided on the command line.

            If this option is not provided -- thus if no white list is
            provided -- then the ABI of all publicly defined and
            exported functions and global variables by the Linux Kernel
            binaries are compared.

          • --no-unreferenced-symbols

            In the resulting report, do not display change information
            about function and variable symbols that are not referenced
            by any debug information.  Note that for these symbols not
            referenced by any debug information, the change information
            displayed is either added or removed symbols.

          • --no-show-locs
              Do not show information about where in the second shared
              library the respective type was changed.

          • --show-bytes

            Show sizes and offsets in bytes, not bits.  By default,
            sizes and offsets are shown in bits.

          • --show-bits

            Show sizes and offsets in bits, not bytes.  This option is
            activated by default.

          • --show-hex

            Show sizes and offsets in hexadecimal base.

          • --show-dec

            Show sizes and offsets in decimal base.  This option is
            activated by default.

          • --no-show-relative-offset-changes

            Without this option, when the offset of a data member
            changes, the change report not only mentions the older and
            newer offset, but it also mentions by how many bits the data
            member changes.  With this option, the latter is not shown.

          • --show-identical-binaries
              Show the names of the all binaries compared, including the
              binaries whose ABI compare equal.  By default, when this
              option is not provided, only binaries with ABI changes are
              mentionned in the output.

          • --fail-no-dbg

            Make the program fail and return a non-zero exit code if
            couldn't read any of the debug information that comes from
            the debug info packages that were given on the command line.
            If no debug info package were provided on the command line
            then this option is not active.

            Note that the non-zero exit code returned by the program as
            a result of this option is the constant ABIDIFF_ERROR.  To
            know the numerical value of that constant, please refer to
            the exit code documentation.

          • --keep-tmp-files

            Do not erase the temporary directory files that are created
            during the execution of the tool.

          • --verbose

            Emit verbose progress messages.

          • --self-check

            This is used to test the underlying Libabigail library.
            When in used, the command expects only on input package,
            along with its associated debug info packages.  The command
            then compares each binary inside the package against its own
            ABIXML representation. The result of the comparison should
            yield the empty set if Libabigail behaves correctly.
            Otherwise, it means there is an issue that ought to be
            fixed.  This option is used by people interested in
            Libabigail development for regression testing purposes.
            Here is an example of the use of this option:

                $ abipkgdiff --self-check --d1 mesa-libGLU-debuginfo-9.0.1-3.fc33.x86_64.rpm  mesa-libGLU-9.0.1-3.fc33.x86_64.rpm
                 ==== SELF CHECK SUCCEEDED for 'libGLU.so.1.3.1' ====
                $

          • --no-assume-odr-for-cplusplus

            When analysing a binary originating from C++ code using
            DWARF debug information, libabigail assumes the One
            Definition Rule to speed-up the analysis.  In that case,
            when several types have the same name in the binary, they
            are assumed to all be equal.

            This option disables that assumption and instructs
            libabigail to actually actually compare the types to
            determine if they are equal.

          • --no-leverage-dwarf-factorization

            When analysing a binary which DWARF debug information was
            processed with the DWZ tool, the type information is
            supposed to be already factorized.  That context is used by
            libabigail to perform some speed optimizations.

            This option disables those optimizations.

          • --ctf
                This is used to compare packages with CTF debug
                information, if present.

          • --btf
                This is used to compare packages with BTF debug
                information, if present.

RETURN VALUE         top

       The exit code of the abipkgdiff command is either 0 if the ABI of
       the binaries compared are equal, or non-zero if they differ or if
       the tool encountered an error.

       In the later case, the value of the exit code is the same as for
       the abidiff tool.

AUTHOR         top

       Dodji Seketeli

COPYRIGHT         top

       2014-2022, Red Hat, Inc.

COLOPHON         top

       This page is part of the libabigail (ABI Generic Analysis and
       Instrumentation Library) project.  Information about the project
       can be found at ⟨https://sourceware.org/libabigail/⟩.  If you
       have a bug report for this manual page, see
       ⟨http://sourceware.org/bugzilla/enter_bug.cgi?product=libabigail⟩.
       This page was obtained from the project's upstream Git repository
       ⟨git://sourceware.org/git/libabigail.git⟩ on 2024-06-14.  (At
       that time, the date of the most recent commit that was found in
       the repository was 2024-05-31.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

                              Jun 14, 2024                 ABIPKGDIFF(1)