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NAME | INVOCATION | ENVIRONMENT | OPTIONS | RETURN VALUES | USAGE EXAMPLES | AUTHOR | COPYRIGHT | COLOPHON |
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ABIDIFF(1) Libabigail ABIDIFF(1)
abidiff - compare ABIs of ELF files
abidiff compares the Application Binary Interfaces (ABI) of two
shared libraries in ELF format. It emits a meaningful report
describing the differences between the two ABIs.
This tool can also compare the textual representations of the ABI
of two ELF binaries (as emitted by abidw) or an ELF binary
against a textual representation of another ELF binary.
For a comprehensive ABI change report between two input shared
libraries that includes changes about function and variable
sub-types, abidiff uses by default, debug information in DWARF
format, if present, otherwise it compares interfaces using debug
information in CTF or 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.
abidiff [options] <first-shared-library> <second-shared-library>
abidiff 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 abidiff 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 abidiff tries to load the suppression
file $HOME/.abignore. If that file is not present, then no
default user suppression specification is loaded.
• --help | -h
Display a short help about the command and exit.
• --debug-self-comparison
In this mode, error messages are emitted for types which
fail type canonicalization, in some circumstances, when
comparing a binary against itself.
When comparing a binary against itself, canonical types of
the second binary should be equal (as much as possible) to
canonical types of the first binary. When some
discrepancies are detected in this mode, an abort signal is
emitted and execution is halted. This option should be used
while executing the tool in a debugger, for troubleshooting
purposes.
This is an optional debugging and sanity check option. To
enable it the libabigail package needs to be configured with
the --enable-debug-self-comparison configure option.
• --debug-tc
In this mode, the process of type canonicalization is put
under heavy scrutiny. Basically, during type
canonicalization, each type comparison is performed twice:
once in a structural mode (comparing every sub-type
member-wise), and once using canonical comparison. The two
comparisons should yield the same result. Otherwise, an
abort signal is emitted and the process can be debugged to
understand why the two kinds of comparison yield different
results.
This is an optional debugging and sanity check option. To
enable it the libabigail package needs to be configured with
the --enable-debug-type-canonicalization configure option.
• --version | -v
Display the version of the program and exit.
• --debug-info-dir1 | --d1 <di-path1>
For cases where the debug information for
first-shared-library is split out into a separate file,
tells abidiff where to find that separate debug information
file.
Note that di-path must point to the root directory under
which the debug information is arranged in a tree-like
manner. Under Red Hat based systems, that directory is
usually <root>/usr/lib/debug.
This option can be provided several times with different
root directories. In that case, abidiff will potentially
look into all those root directories to find the split debug
info for first-shared-library.
Note also that this option is not mandatory for split debug
information installed by your system's package manager
because then abidiff knows where to find it.
• --debug-info-dir2 | --d2 <di-path2>
Like --debug-info-dir1, this options tells abidiff where to
find the split debug information for the
second-shared-library file.
This option can be provided several times with different
root directories. In that case, abidiff will potentially
look into all those root directories to find the split debug
info for second-shared-library.
• --headers-dir1 | --hd1 <headers-directory-path-1>
Specifies where to find the public headers of the first
shared library (or binary in general) that the tool has to
consider. The tool will thus filter out ABI changes on
types that are not defined in public headers.
Note that several public header directories can be specified
for the first shared library. In that case the
--headers-dir1 option should be present several times on the
command line, like in the following example:
$ abidiff --headers-dir1 /some/path \
--headers-dir1 /some/other/path \
binary-version-1 binary-version-2
• --header-file1 | --hf1 <header-file-path-1>
Specifies where to find one public header of the first
shared library that the tool has to consider. The tool will
thus filter out ABI changes on types that are not defined in
public headers.
• --headers-dir2 | --hd2 <headers-directory-path-2>
Specifies where to find the public headers of the second
shared library that the tool has to consider. The tool will
thus filter out ABI changes on types that are not defined in
public headers.
Note that several public header directories can be specified
for the second shared library. In that case the
--headers-dir2 option should be present several times like
in the following example:
$ abidiff --headers-dir2 /some/path \
--headers-dir2 /some/other/path \
binary-version-1 binary-version-2
• --header-file2 | --hf2 <header-file-path-2>
Specifies where to find one public header of the second
shared library that the tool has to consider. The tool will
thus filter out ABI changes on types that are not defined in
public headers.
• --add-binaries1 <bin1,bin2,bin3,..>
For each of the comma-separated binaries given in argument
to this option, if the binary is found in the directory
specified by the --added-binaries-dir1 option, then abidiff
loads the ABI corpus of the binary and adds it to a set of
corpora (called an ABI Corpus Group) that includes the first
argument of abidiff.
That ABI corpus group is then compared against the second
corpus group given in argument to abidiff.
• --add-binaries2 <bin1,bin2,bin3,..>
For each of the comma-separated binaries given in argument
to this option, if the binary is found in the directory
specified by the --added-binaries-dir2 option, then abidiff
loads the ABI corpus of the binary and adds it to a set of
corpora(called an ABI Corpus Group) that includes the second
argument of abidiff.
That ABI corpus group is then compared against the first
corpus group given in argument to abidiff.
• --follow-dependencies | --fdeps
For each dependency of the first argument of abidiff, if
it's found in the directory specified by the
--added-binaries-dir1 option, then construct an ABI corpus
out of the dependency, add it to a set of corpora (called an
ABI Corpus Group) that includes the first argument of
abidiff.
Similarly, for each dependency of the second argument of
abidiff, if it's found in the directory specified by the
--added-binaries-dir2 option, then construct an ABI corpus
out of the dependency, add it to an ABI corpus group that
includes the second argument of abidiff.
These two ABI corpus groups are then compared against each
other.
Said otherwise, this makes abidiff compare the set of its
first input and its dependencies against the set of its
second input and its dependencies.
• list-dependencies | --ldeps
This option lists all the dependencies of the input
arguments of abidiff that are found in the directories
specified by the options --added-binaries-dir1 and
--added-binaries-dir2
• --added-binaries-dir1 | --abd1 <added-binaries-directory-1>
This option is to be used in conjunction with the
--add-binaries1, --follow-dependencies and
--list-dependencies options. Binaries referred to by these
options, if found in the directory
added-binaries-directory-1, are loaded as ABI corpus and are
added to the first ABI corpus group that is to be used in
the comparison.
• --added-binaries-dir2 | --abd2 <added-binaries-directory-2>
This option is to be used in conjunction with the
--add-binaries2, --follow-dependencies and
--list-dependencies options. Binaries referred to by these
options, if found in the directory
added-binaries-directory-2, are loaded as ABI corpus and are
added to the second ABI corpus group to be used in the
comparison.
• --no-linux-kernel-mode
Without this option, if abidiff detects that the binaries it
is looking at are Linux Kernel binaries (either vmlinux or
modules) then it only considers functions and variables
which ELF symbols are listed in the __ksymtab and
__ksymtab_gpl sections.
With this option, abidiff considers the binary as a
non-special ELF binary. It thus considers functions and
variables which are defined and exported in the ELF sense.
• --kmi-whitelist | -kaw <path-to-whitelist>
When analyzing a Linux kernel binary, this option points to
the white list of names of ELF symbols of functions and
variables which ABI must be considered. That white list is
called a "Kernel Module Interface white list". This is
because for the Kernel, we don't talk about ABI; we rather
talk about the interface between the Kernel and its module.
Hence the term KMI rather than ABI.
Any other function or variable which ELF symbol are not
present in that white list will not be considered by this
tool.
If this option is not provided -- thus if no white list is
provided -- then the entire KMI, that is, the set of all
publicly defined and exported functions and global variables
by the Linux Kernel binaries, is considered.
• --drop-private-types
This option is to be used with the --headers-dir1,
header-file1, header-file2 and --headers-dir2 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.
• --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.
• --stat
Rather than displaying the detailed ABI differences between
first-shared-library and second-shared-library, just display
some summary statistics about these differences.
• --symtabs
Only display the symbol tables of the first-shared-library
and second-shared-library.
• --deleted-fns
In the resulting report about the differences between
first-shared-library and second-shared-library, only display
the globally defined functions that got deleted from
first-shared-library.
• --changed-fns
In the resulting report about the differences between
first-shared-library and second-shared-library, only display
the changes in sub-types of the global functions defined in
first-shared-library.
• --added-fns
In the resulting report about the differences between
first-shared-library and second-shared-library, only display
the globally defined functions that were added to
second-shared-library.
• --deleted-vars
In the resulting report about the differences between
first-shared-library and second-shared-library, only display
the globally defined variables that were deleted from
first-shared-library.
• --changed-vars
In the resulting report about the differences between
first-shared-library and second-shared-library, only display
the changes in the sub-types of the global variables defined
in first-shared-library
• --added-vars
In the resulting report about the differences between
first-shared-library and second-shared-library, only display
the global variables that were added (defined) to
second-shared-library.
• --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 --headers-dir{1,2} and/or header-file{1,2}
options, the additional non-reachable types analyzed are
restricted to those defined in public headers files, 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.
• --no-added-syms
In the resulting report about the differences between
first-shared-library and second-shared-library, do not
display added functions or variables. Do not display added
functions or variables ELF symbols either. All other kinds
of changes are displayed unless they are explicitely
forbidden by other options on the command line.
• --no-linkage-name
In the resulting report, do not display the linkage names of
the added, removed, or changed functions or variables.
• --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.
• --ignore-soname
Ignore differences in the SONAME when doing a comparison
• --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.
• --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-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 provided 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 .
• --drop <regex>
When reading the first-shared-library and
second-shared-library ELF input files, drop the globally
defined functions and variables which name match the regular
expression regex. As a result, no change involving these
functions or variables will be emitted in the diff report.
• --drop-fn <regex>
When reading the first-shared-library and
second-shared-library ELF input files, drop the globally
defined functions which name match the regular expression
regex. As a result, no change involving these functions
will be emitted in the diff report.
• --drop-var <regex>
When reading the first-shared-library and
second-shared-library ELF input files, drop the globally
defined variables matching a the regular expression regex.
• --keep <regex>
When reading the first-shared-library and
second-shared-library ELF input files, keep the globally
defined functions and variables which names match the
regular expression regex. All other functions and variables
are dropped on the floor and will thus not appear in the
resulting diff report.
• --keep-fn <regex>
When reading the first-shared-library and
second-shared-library ELF input files, keep the globally
defined functions which name match the regular expression
regex. All other functions are dropped on the floor and
will thus not appear in the resulting diff report.
• --keep-var <regex>
When reading the first-shared-library and
second-shared-library ELF input files, keep the globally
defined which names match the regular expression regex. All
other variables are dropped on the floor and will thus not
appear in the resulting diff 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-harmful
In the diff report, do not display the harmful changes. By
default, only the harmful changes are displayed in diff
report.
• --redundant
In the diff report, do display redundant changes. A
redundant change is a change that has been displayed
elsewhere in the report.
• --no-redundant
In the diff report, do NOT display redundant changes. A
redundant change is a change that has been displayed
elsewhere in the report. This option is switched on by
default.
• --no-architecture
Do not take architecture in account when comparing ABIs.
• --no-corpus-path
Do not emit the path attribute for the ABI corpus.
• --fail-no-debug-info
If no debug info was found, then this option makes the
program to fail. Otherwise, without this option, the
program will attempt to compare properties of the binaries
that are not related to debug info, like pure ELF
properties.
• --leaf-changes-only|-l only show leaf changes, so don't show
impact analysis report. This option implies --redundant.
The typical output of abidiff when comparing two binaries
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 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 by showing the list of interfaces
impacted by the leaf change.
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.
• --impacted-interfaces
When showing leaf changes, this option instructs abidiff to
show the list of impacted interfaces. This option is thus
to be used in addition the --leaf-changes-only option,
otherwise, it's ignored.
• --dump-diff-tree
After the diff report, emit a textual representation of
the diff nodes tree used by the comparison engine to
represent the changed functions and variables. That
representation is emitted to the error output for
debugging purposes. Note that this diff tree is relevant
only to functions and variables that have some sub-type
changes. Added or removed functions and variables do not
have any diff nodes tree associated to them.
• --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.
• --no-change-categorization | -x
This option disables the categorization of changes into
harmless and harmful changes. Note that this categorization
is a pre-requisite for the filtering of changes so this
option disables that filtering. The goal of this option is
to speed-up the execution of the program for cases where the
graph of changes is huge and where the user is just
interested in looking at, for instance, leaf node changes
without caring about their possible impact on interfaces.
In that case, this option would be used along with the
--leaf-changes-only one.
• --ctf
When comparing binaries, extract ABI information from CTF
debug information, if present.
• --btf
When comparing binaries, extract ABI information from BTF
debug information, if present.
• --stats
Emit statistics about various internal things.
• --verbose
Emit verbose logs about the progress of miscellaneous
internal things.
The exit code of the abidiff command is either 0 if the ABI of
the binaries being compared are equal, or non-zero if they differ
or if the tool encountered an error.
In the later case, the exit code is a 8-bits-wide bit field in
which each bit has a specific meaning.
The first bit, of value 1, named ABIDIFF_ERROR means there was an
error.
The second bit, of value 2, named ABIDIFF_USAGE_ERROR means there
was an error in the way the user invoked the tool. It might be
set, for instance, if the user invoked the tool with an unknown
command line switch, with a wrong number or argument, etc. If
this bit is set, then the ABIDIFF_ERROR bit must be set as well.
The third bit, of value 4, named ABIDIFF_ABI_CHANGE means the ABI
of the binaries being compared are different.
The fourth bit, of value 8, named ABIDIFF_ABI_INCOMPATIBLE_CHANGE
means the ABI of the binaries compared are different in an
incompatible way. If this bit is set, then the
ABIDIFF_ABI_CHANGE bit must be set as well. If the
ABIDIFF_ABI_CHANGE is set and the ABIDIFF_INCOMPATIBLE_CHANGE is
NOT set, then it means that the ABIs being compared might or
might not be compatible. In that case, a human being needs to
review the ABI changes to decide if they are compatible or not.
Note that, at the moment, there are only a few kinds of ABI
changes that would result in setting the flag
ABIDIFF_ABI_INCOMPATIBLE_CHANGE. Those ABI changes are either:
• the removal of the symbol of a function or variable that has
been defined and exported.
• the modification of the index of a member of a virtual
function table (for C++ programs and libraries).
With time, when more ABI change patterns are found to always
constitute incompatible ABI changes, we will adapt the code to
recognize those cases and set the ABIDIFF_ABI_INCOMPATIBLE_CHANGE
accordingly. So, if you find such patterns, please let us know.
The remaining bits are not used for the moment.
1. Detecting a change in a sub-type of a function:
$ cat -n test-v0.cc
1 // Compile this with:
2 // g++ -g -Wall -shared -o libtest-v0.so test-v0.cc
3
4 struct S0
5 {
6 int m0;
7 };
8
9 void
10 foo(S0* /*parameter_name*/)
11 {
12 // do something with parameter_name.
13 }
$
$ cat -n test-v1.cc
1 // Compile this with:
2 // g++ -g -Wall -shared -o libtest-v1.so test-v1.cc
3
4 struct type_base
5 {
6 int inserted;
7 };
8
9 struct S0 : public type_base
10 {
11 int m0;
12 };
13
14 void
15 foo(S0* /*parameter_name*/)
16 {
17 // do something with parameter_name.
18 }
$
$ g++ -g -Wall -shared -o libtest-v0.so test-v0.cc
$ g++ -g -Wall -shared -o libtest-v1.so test-v1.cc
$
$ ../build/tools/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 foo(S0*)' has some indirect sub-type changes:
parameter 0 of type 'S0*' has sub-type changes:
in pointed to type 'struct S0':
size changed from 32 to 64 bits
1 base class insertion:
struct type_base
1 data member change:
'int S0::m0' offset changed from 0 to 32
$
2. Detecting another change in a sub-type of a function:
$ cat -n test-v0.cc
1 // Compile this with:
2 // g++ -g -Wall -shared -o libtest-v0.so test-v0.cc
3
4 struct S0
5 {
6 int m0;
7 };
8
9 void
10 foo(S0& /*parameter_name*/)
11 {
12 // do something with parameter_name.
13 }
$
$ cat -n test-v1.cc
1 // Compile this with:
2 // g++ -g -Wall -shared -o libtest-v1.so test-v1.cc
3
4 struct S0
5 {
6 char inserted_member;
7 int m0;
8 };
9
10 void
11 foo(S0& /*parameter_name*/)
12 {
13 // do something with parameter_name.
14 }
$
$ g++ -g -Wall -shared -o libtest-v0.so test-v0.cc
$ g++ -g -Wall -shared -o libtest-v1.so test-v1.cc
$
$ ../build/tools/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 foo(S0&)' has some indirect sub-type changes:
parameter 0 of type 'S0&' has sub-type changes:
in referenced type 'struct S0':
size changed from 32 to 64 bits
1 data member insertion:
'char S0::inserted_member', at offset 0 (in bits)
1 data member change:
'int S0::m0' offset changed from 0 to 32
$
3. Detecting that functions got removed or added to a library:
$ cat -n test-v0.cc
1 // Compile this with:
2 // g++ -g -Wall -shared -o libtest-v0.so test-v0.cc
3
4 struct S0
5 {
6 int m0;
7 };
8
9 void
10 foo(S0& /*parameter_name*/)
11 {
12 // do something with parameter_name.
13 }
$
$ cat -n test-v1.cc
1 // Compile this with:
2 // g++ -g -Wall -shared -o libtest-v1.so test-v1.cc
3
4 struct S0
5 {
6 char inserted_member;
7 int m0;
8 };
9
10 void
11 bar(S0& /*parameter_name*/)
12 {
13 // do something with parameter_name.
14 }
$
$ g++ -g -Wall -shared -o libtest-v0.so test-v0.cc
$ g++ -g -Wall -shared -o libtest-v1.so test-v1.cc
$
$ ../build/tools/abidiff libtest-v0.so libtest-v1.so
Functions changes summary: 1 Removed, 0 Changed, 1 Added functions
Variables changes summary: 0 Removed, 0 Changed, 0 Added variable
1 Removed function:
'function void foo(S0&)' {_Z3fooR2S0}
1 Added function:
'function void bar(S0&)' {_Z3barR2S0}
$
4. Comparing two sets of binaries that are passed on the
command line:
$ abidiff --add-binaries1=file2-v1 \
--add-binaries2=file2-v2,file2-v1 \
--added-binaries-dir1 dir1 \
--added-binaries-dir2 dir2 \
file1-v1 file1-v2
Note that the files file2-v1, and file2-v2 are to be found
in dir1 and dir2 or in the current directory.
5. Compare two libraries and their dependencies:
$ abidiff --follow-dependencies \
--added-binaries-dir1 /some/where \
--added-binaries-dir2 /some/where/else \
foo bar
This compares the set of binaries comprised by foo and its
dependencies against the set of binaries comprised by bar
and its dependencies.
Dodji Seketeli
2014-2022, Red Hat, Inc.
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:https://sourceware.org/bugzilla/enter_bug.cgi?product=libabigail⟩.
This page was obtained from the project's upstream Git repository
⟨git:https://sourceware.org/git/libabigail.git⟩ on 2023-12-22. (At
that time, the date of the most recent commit that was found in
the repository was 2023-12-01.) 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
[email protected]
Dec 22, 2023 ABIDIFF(1)
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