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From: Dodji Seketeli <dodji@redhat.com>
To: dodji@redhat.com
Cc: libabigail@sourceware.org
Subject: [PATCH 1/4] Represent undefined corpus interfaces to analyze app compatibility
Date: Thu, 14 Mar 2024 17:57:49 +0100	[thread overview]
Message-ID: <87plvw3g4y.fsf@redhat.com> (raw)
In-Reply-To: <87ttl83gaw.fsf@redhat.com> (Dodji Seketeli's message of "Thu, 14 Mar 2024 17:54:15 +0100")

[-- Attachment #1: Type: text/plain, Size: 19366 bytes --]

Hello,

In the text below, the term interface means the "declaration of either
a function or a global variable".

To analyze the compatibility between an application and a dependent
library, one has essentially to analyze the interfaces of the
application that have undefined symbols (aka undefined interfaces from
the application) and see how they relate to the same interfaces coming
from the library but with symbols that are defined and exported from
the library (aka defined/exported interfaces from the library).

An interface that is undefined in the application and defined in the
library is an interface that the application consumes from the
library.

In other words an undefined interface from an application is an
interface that the application expects and an interface that is
exported by a library is an interface that the library provides.

If comparing the expected interface against the provided interface
yields a meaningful difference, then that might mean there is an
incompatibility between the application and the library on that
interface.

This patch uses this scheme to re-implement the weak mode of ABI
compatibility between an application and a library.

The patch adds the concept of undefined functions and variables to the
ABI corpus.  Then it teaches the DWARF reader how to construct the IR
for these undefined interfaces.  Then it revisits the weak mode of
operation of abicompat to make it compare the interfaces expected from
the application against the corresponding interfaces provided by
library.  The patch also teaches the weak mode abicompat how to detect
incompatibilities between the interfaces that plugin expects and the
interfaces provided by the application.

This patch makes the CTF front-end construct undefined interfaces.  A
subsequent patch is needed to construct undefined interfaces from the
BTF front-end however.

	* include/abg-corpus.h (corpus::{lookup_variable,
	get_undefined_functions, get_undefined_variables}): Declare new
	member functions.
	(corpus::exported_decls_builder::maybe_add_{fn,var}_to_exported_fns):
	Make this return a boolean.
	* include/abg-fe-iface.h (fe_iface::options_type): Add a new
	load_undefined_interfaces enumerator.
	(fe_iface::add_fn_to_exported_or_undefined_decls): Rename
	maybe_add_fn_to_exported_decls into this.
	(fe_iface::add_var_to_exported_or_undefined_decls): Rename
	maybe_add_var_to_exported_decls into this.
	* src/abg-btf-reader.cc (reader::build_ir_node_from_btf_type):
	Adjust call to maybe_add_fn_to_exported_decls as
	add_fn_to_exported_or_undefined_decls.  Similarly, adjust call to
	maybe_add_var_to_exported_decls as
	add_var_to_exported_or_undefined_decls.
	* src/abg-corpus-priv.h (corpus::priv::undefined_{fns,vars}): Add
	new member variables.
	* src/abg-corpus.cc
	(corpus::exported_decls_builder::maybe_add_{fn,var}_to_exported_fns):
	Return a bool iff the decl was added to the set of exported decls.
	(corpus::{lookup_variable, get_undefined_functions,
	get_undefined_variables}): Define new member functions.
	(corpus::sort_{functions,variables}): Sort the undefined decls
	too.
	* (corpus::lookup_{function,variable}_symbol): Lookup the symbol
	also among undefined symbols, not just among defined symbols.
	* src/abg-ctf-reader.cc (reader::process_ctf_archive): Adjust call
	to maybe_add_fn_to_exported_decls as
	add_fn_to_exported_or_undefined_decls.  Similarly, adjust call to
	maybe_add_var_to_exported_decls as
	add_var_to_exported_or_undefined_decls. Also, sort functions &
	variables in the corpus.
	* src/abg-dwarf-reader.cc (die_name_and_linkage_name): Define new
	static function.
	(reader::fixup_functions_with_no_symbols): Adjust call to
	maybe_add_fn_to_exported_decls as
	add_fn_to_exported_or_undefined_decls.
	(reader::{is_decl_die_with_undefined_symbol,
	load_undefined_interfaces}): Define new member functions.
	(build_translation_unit_and_add_to_ir): Analyze DIEs of interfaces
	that have undefined symbols if we were asked to load undefined
	interfaces.
	(variable_is_suppressed): Add a boolean parameter to tell if the
	var is decl-only.  Use that decl-only flag to determine if the
	variable is suppressed.  A non-member decl-only variable won't be
	suppressed if we were asked to load undefined interfaces.
	(build_or_get_var_decl_if_not_suppressed): Add a boolean parameter
	to tell if the var is decl-only.
	(potential_member_fn_should_be_dropped): A potential non-virtual
	member function with no symbol is now dropped on the floor
	regardless of it has a mangled name or not.
	(build_var_decl): If the var has an undefined symbol, then set
	that symbol.
	(build_function_decl): If the function has an undefined symbol,
	then set that symbol.
	(build_ir_node_from_die): Add a var or function with undefined
	symbol to the set of undefined vars or functions of the current
	corpus.
	* src/abg-fe-iface.cc
	(fe_iface::add_fn_to_exported_or_undefined_decls): Renamed
	fe_iface::maybe_add_fn_to_exported_decls into this.  If the
	function has an undefined symbol then add the function to the set
	of undefined functions.
	(fe_iface::add_var_to_exported_or_undefined_decls): Renamed
	fe_iface::maybe_add_var_to_exported_decls into this.  If the
	variable has an undefined symbol then add the variable to the set
	of undefined variables.
	* src/abg-ir.cc (elf_symbol::is_variable): Undefined symbol with
	type STT_NOTYPE are actually for undefined variables.
	(maybe_adjust_canonical_type): It's here, after type
	canonicalization that a member function is added to either the set
	of defined & exported functions, or to the set of functions with
	undefined symbols.
	* src/abg-reader.cc (build_function_decl, build_class_decl)
	(build_union_decl, handle_var_decl): Adjust.
	* src/abg-symtab-reader.cc
	(symtab::{lookup_undefined_function_symbol,
	lookup_undefined_variable_symbol, function_symbol_is_undefined,
	variable_symbol_is_undefined,
	collect_undefined_fns_and_vars_linkage_names}): Define new member
	functions.
	(symtab::symtab): Initialize the new
	cached_undefined_symbol_names_ data member.
	* src/abg-symtab-reader.h
	(symtab::{lookup_undefined_function_symbol,
	lookup_undefined_variable_symbol, function_symbol_is_undefined,
	variable_symbol_is_undefined,
	collect_undefined_fns_and_vars_linkage_names}): Declare new member
	functions.
	(symtab::{undefined_variable_linkage_names_,
	cached_undefined_symbol_names_}): Define new data members.
	(symtab::load_): Consider undefined symbol of type STT_NOTYPE as
	being undefined global variables.  It's what I am seeing in ELF
	binaries.
	* src/abg-symtab-reader.h
	(symtab::{lookup_undefined_function_symbol,
	lookup_undefined_variable_symbol, function_symbol_is_undefined,
	variable_symbol_is_undefined}): Declare new member functions.
	(symtab::{undefined_function_linkage_names_,
	undefined_variable_linkage_names_}): Define new member variables.
	* src/abg-writer.cc (write_var_decl, write_function_decl): Emit a
	reference to a symbol only when the symbol is defined.
	* tools/abicompat.cc (report_function_changes)
	(report_variable_changes)
	(compare_expected_against_provided_functions)
	(compare_expected_against_provided_variables): Define new static
	functions.
	(perform_compat_check_in_weak_mode): Use the new static functions
	above. Compare interfaces expected by the application corpus
	against interfaces provided by the library.  Report the changes.
	Do that in the reverse direction as well.
	(read_corpus): Instruct the corpus reader to load the set of
	undefined interfaces too.
	* tests/data/test-abicompat/test6-var-changed-app: Remove file.
	* tests/data/test-abicompat/test6-var-changed-app.cc: Likewise.
	* tests/data/test-abicompat/libtest6-undefined-var.so: Add new
	binary input file.
	* tests/data/test-abicompat/test6-undefined-var.cc: Add sourcefile
	for the binary input file above.
	* tests/data/test-abicompat/test6-var-changed-report-2.txt: New
	reference output file.
	* tests/data/Makefile.am: Update the list of distributed files
	accordingly.
	* tests/data/test-abicompat/libtest5-fn-changed-libapp-v0.so:
	Adjust.
	* tests/data/test-abicompat/libtest5-fn-changed-libapp-v1.so:
	Likewise.
	* tests/data/test-abicompat/libtest6-var-changed-libapp-v0.so:
	Likewise.
	* tests/data/test-abicompat/libtest6-var-changed-libapp-v1.so:
	Likewise.
	* tests/data/test-abicompat/libtest7-fn-changed-libapp-v0.so:
	Likewise.
	* tests/data/test-abicompat/libtest7-fn-changed-libapp-v1.so:
	Likewise.
	* tests/data/test-abicompat/libtest8-fn-changed-libapp-v0.so:
	Likewise.
	* tests/data/test-abicompat/libtest8-fn-changed-libapp-v1.so:
	Likewise.
	* tests/data/test-abicompat/libtest9-fn-changed-v0.so: Likewise.
	* tests/data/test-abicompat/libtest9-fn-changed-v1.so: Likewise.
	* tests/data/test-abicompat/test5-fn-changed-app: Likewise.
	* tests/data/test-abicompat/test6-var-changed-libapp-v0.cc:
	Likewise.
	* tests/data/test-abicompat/test6-var-changed-libapp-v1.cc:
	Likewise.
	* tests/data/test-abicompat/test6-var-changed-report-0.txt:
	Likewise.
	* tests/data/test-abicompat/test6-var-changed-report-1.txt:
	Likewise.
	* tests/data/test-abicompat/test7-fn-changed-app: Likewise.
	* tests/data/test-abicompat/test7-fn-changed-report-1.txt:
	Likewise.
	* tests/data/test-abicompat/test7-fn-changed-report-2.txt:
	Likewise.
	* tests/data/test-abicompat/test8-fn-changed-app: Likewise.
	* tests/data/test-abicompat/test8-fn-changed-libapp-v1.c:
	Likewise.
	* tests/data/test-abicompat/test9-fn-changed-app: Likewise.
	* tests/data/test-abicompat/test9-fn-changed-app.cc: Likewise.
	* tests/data/test-annotate/libtest23.so.abi: Likewise.
	* tests/data/test-annotate/libtest24-drop-fns-2.so.abi: Likewise.
	* tests/data/test-annotate/libtest24-drop-fns.so.abi: Likewise.
	* tests/data/test-annotate/test1.abi: Likewise.
	* tests/data/test-annotate/test14-pr18893.so.ab: Likewise.i
	* tests/data/test-annotate/test15-pr18892.so.abi: Likewise.
	* tests/data/test-annotate/test17-pr19027.so.abi: Likewise.
	* tests/data/test-annotate/test18-pr19037-libvtkRenderingLIC-6.1.so.abi:
	Likewise.
	* tests/data/test-annotate/test19-pr19023-libtcmalloc_and_profiler.so.abi:
	Likewise.
	* tests/data/test-annotate/test2.so.abi: Likewise.
	* tests/data/test-annotate/test20-pr19025-libvtkParallelCore-6.1.so.abi:
	Likewise.
	* tests/data/test-annotate/test21-pr19092.so.abi: Likewise.
	* tests/data/test-annotate/test8-qualified-this-pointer.so.abi:
	Likewise.
	* tests/data/test-diff-pkg/dbus-glib-0.104-3.fc23.x86_64--dbus-glib-0.104-3.fc23.armv7hl-report-0.txt:
	Likewise.
	* tests/data/test-diff-pkg/libICE-1.0.6-1.el6.x86_64.rpm--libICE-1.0.9-2.el7.x86_64.rpm-report-0.txt:
	Likewise.
	* tests/data/test-fedabipkgdiff/test0-from-fc20-to-fc23-dbus-glib-report-0.txt:
	Likewise.
	* tests/data/test-fedabipkgdiff/test2-dbus-glib-0.100.2-2.fc20--dbus-glib-0.106-1.fc23-report-0.txt:
	Likewise.
	* tests/data/test-fedabipkgdiff/test3-dbus-glib-0.100.2-2.fc20.i686--dbus-glib-0.106-1.fc23.i686-report-0.txt:
	Likewise.
	* tests/data/test-fedabipkgdiff/vte291-0.39.1-1.fc22.x86_64--vte291-0.39.90-1.fc22.x86_64-report-0.txt:
	Likewise.
	* tests/data/test-read-dwarf/PR22015-libboost_iostreams.so.abi:
	Likewise.
	* tests/data/test-read-dwarf/PR22122-libftdc.so.abi: Likewise.
	* tests/data/test-read-dwarf/PR26261/PR26261-exe.abi: Likewise.
	* tests/data/test-read-dwarf/libtest23.so.abi: Likewise.
	* tests/data/test-read-dwarf/libtest24-drop-fns-2.so.abi:
	Likewise.
	* tests/data/test-read-dwarf/libtest24-drop-fns.so.abi: Likewise.
	* tests/data/test-read-dwarf/test-libaaudio.so.abi: Likewise.
	* tests/data/test-read-dwarf/test-libandroid.so.abi: Likewise.
	* tests/data/test-read-dwarf/test1.abi: Likewise.
	* tests/data/test-read-dwarf/test1.hash.abi: Likewise.
	* tests/data/test-read-dwarf/test10-pr18818-gcc.so.abi: Likewise.
	* tests/data/test-read-dwarf/test11-pr18828.so.abi: Likewise.
	* tests/data/test-read-dwarf/test12-pr18844.so.abi: Likewise.
	* tests/data/test-read-dwarf/test14-pr18893.so.abi: Likewise.
	* tests/data/test-read-dwarf/test15-pr18892.so.abi: Likewise.
	* tests/data/test-read-dwarf/test16-pr18904.so.abi: Likewise.
	* tests/data/test-read-dwarf/test17-pr19027.so.abi: Likewise.
	* tests/data/test-read-dwarf/test18-pr19037-libvtkRenderingLIC-6.1.so.abi:
	Likewise.
	* tests/data/test-read-dwarf/test19-pr19023-libtcmalloc_and_profiler.so.abi:
	Likewise.
	* tests/data/test-read-dwarf/test2.so.abi: Likewise.
	* tests/data/test-read-dwarf/test2.so.hash.abi: Likewise.
	* tests/data/test-read-dwarf/test20-pr19025-libvtkParallelCore-6.1.so.abi:
	Likewise.
	* tests/data/test-read-dwarf/test21-pr19092.so.abi: Likewise.
	* tests/data/test-read-dwarf/test22-pr19097-libstdc++.so.6.0.17.so.abi:
	Likewise.
	* tests/data/test-read-dwarf/test8-qualified-this-pointer.so.abi:
	Likewise.
	* tests/data/test-read-dwarf/test8-qualified-this-pointer.so.hash.abi:
	Likewise.
	* tests/data/test-read-dwarf/test9-pr18818-clang.so.abi: Likewise.
	* tests/test-abicompat.cc (in_out_specs): Adjust.
	* tests/test-read-ctf.cc (test_task_ctf::perform): Do not load
	undefined interfaces, by default.
	* tests/test-symtab.cc (Symtab::SimpleSymtabs)
	(Symtab::SymtabWithWhitelist, Symtab::AliasedFunctionSymbols):
	Adjust the expected undefined variable symbols counts.

Signed-off-by: Dodji Seketeli <dodji@redhat.com>
---
 include/abg-corpus.h                          |    31 +-
 include/abg-fe-iface.h                        |     8 +-
 src/abg-btf-reader.cc                         |     4 +-
 src/abg-corpus-priv.h                         |     6 +-
 src/abg-corpus.cc                             |   165 +-
 src/abg-ctf-reader.cc                         |     6 +-
 src/abg-dwarf-reader.cc                       |   185 +-
 src/abg-fe-iface.cc                           |    43 +-
 src/abg-ir.cc                                 |    24 +-
 src/abg-reader.cc                             |    10 +-
 src/abg-symtab-reader.cc                      |   115 +-
 src/abg-symtab-reader.h                       |    23 +
 src/abg-writer.cc                             |     8 +-
 tests/data/Makefile.am                        |     5 +-
 .../libtest5-fn-changed-libapp-v0.so          |   Bin 9611 -> 18112 bytes
 .../libtest5-fn-changed-libapp-v1.so          |   Bin 9587 -> 18080 bytes
 .../test-abicompat/libtest6-undefined-var.so  |   Bin 0 -> 17688 bytes
 .../libtest6-var-changed-libapp-v0.so         |   Bin 9486 -> 17976 bytes
 .../libtest6-var-changed-libapp-v1.so         |   Bin 9462 -> 17984 bytes
 .../libtest7-fn-changed-libapp-v0.so          |   Bin 9438 -> 17968 bytes
 .../libtest7-fn-changed-libapp-v1.so          |   Bin 9462 -> 17992 bytes
 .../libtest8-fn-changed-libapp-v0.so          |   Bin 8940 -> 17376 bytes
 .../libtest8-fn-changed-libapp-v1.so          |   Bin 8972 -> 17416 bytes
 .../test-abicompat/libtest9-fn-changed-v0.so  |   Bin 9004 -> 17456 bytes
 .../test-abicompat/libtest9-fn-changed-v1.so  |   Bin 9036 -> 17488 bytes
 .../data/test-abicompat/test5-fn-changed-app  |   Bin 9881 -> 26040 bytes
 .../test-abicompat/test6-undefined-var.cc     |    12 +
 .../data/test-abicompat/test6-var-changed-app |   Bin 9822 -> 0 bytes
 .../test-abicompat/test6-var-changed-app.cc   |    15 -
 .../test6-var-changed-libapp-v0.cc            |     1 +
 .../test6-var-changed-libapp-v1.cc            |     1 +
 .../test6-var-changed-report-0.txt            |     2 +-
 .../test6-var-changed-report-1.txt            |     2 +-
 .../test6-var-changed-report-2.txt            |    15 +
 .../data/test-abicompat/test7-fn-changed-app  |   Bin 9938 -> 26008 bytes
 .../test7-fn-changed-report-1.txt             |     5 +
 .../test7-fn-changed-report-2.txt             |     5 +
 .../data/test-abicompat/test8-fn-changed-app  |   Bin 9700 -> 25864 bytes
 .../test8-fn-changed-libapp-v1.c              |     2 +-
 .../data/test-abicompat/test9-fn-changed-app  |   Bin 10035 -> 26008 bytes
 .../test-abicompat/test9-fn-changed-app.cc    |     2 +-
 tests/data/test-annotate/libtest23.so.abi     |   711 +-
 .../test-annotate/libtest24-drop-fns-2.so.abi |   576 -
 .../test-annotate/libtest24-drop-fns.so.abi   |   576 -
 tests/data/test-annotate/test1.abi            |    74 +-
 .../data/test-annotate/test14-pr18893.so.abi  | 14336 +---
 .../data/test-annotate/test15-pr18892.so.abi  | 25174 ++-----
 .../data/test-annotate/test17-pr19027.so.abi  | 18027 +----
 ...st18-pr19037-libvtkRenderingLIC-6.1.so.abi | 30166 +++-----
 ...19-pr19023-libtcmalloc_and_profiler.so.abi | 27423 ++-----
 tests/data/test-annotate/test2.so.abi         |    36 -
 ...st20-pr19025-libvtkParallelCore-6.1.so.abi | 28876 ++------
 .../data/test-annotate/test21-pr19092.so.abi  |  4308 +-
 .../test8-qualified-this-pointer.so.abi       |    21 +-
 ...bus-glib-0.104-3.fc23.armv7hl-report-0.txt |     7 +-
 ...libICE-1.0.9-2.el7.x86_64.rpm-report-0.txt |     6 +-
 ...0-from-fc20-to-fc23-dbus-glib-report-0.txt |     7 -
 ....fc20--dbus-glib-0.106-1.fc23-report-0.txt |     7 -
 ...--dbus-glib-0.106-1.fc23.i686-report-0.txt |     7 -
 ...-vte291-0.39.90-1.fc22.x86_64-report-0.txt |    13 +-
 .../PR22015-libboost_iostreams.so.abi         |  2466 +-
 .../test-read-dwarf/PR22122-libftdc.so.abi    |  3425 +-
 .../test-read-dwarf/PR26261/PR26261-exe.abi   |    42 +-
 tests/data/test-read-dwarf/libtest23.so.abi   |   411 +-
 .../libtest24-drop-fns-2.so.abi               |   321 -
 .../test-read-dwarf/libtest24-drop-fns.so.abi |   321 -
 .../test-read-dwarf/test-libaaudio.so.abi     |  1398 +-
 .../test-read-dwarf/test-libandroid.so.abi    | 38724 ++++------
 tests/data/test-read-dwarf/test1.abi          |    54 +-
 tests/data/test-read-dwarf/test1.hash.abi     |    32 -
 .../test-read-dwarf/test10-pr18818-gcc.so.abi |  4340 +-
 .../test-read-dwarf/test11-pr18828.so.abi     |  8812 +--
 .../test-read-dwarf/test12-pr18844.so.abi     | 17781 +----
 .../test-read-dwarf/test14-pr18893.so.abi     |  7500 +-
 .../test-read-dwarf/test15-pr18892.so.abi     | 20419 ++----
 .../test-read-dwarf/test16-pr18904.so.abi     |  6042 +-
 .../test-read-dwarf/test17-pr19027.so.abi     | 13682 +---
 ...st18-pr19037-libvtkRenderingLIC-6.1.so.abi | 18170 ++---
 ...19-pr19023-libtcmalloc_and_profiler.so.abi | 19957 ++----
 tests/data/test-read-dwarf/test2.so.abi       |    24 -
 tests/data/test-read-dwarf/test2.so.hash.abi  |    24 -
 ...st20-pr19025-libvtkParallelCore-6.1.so.abi | 17154 +----
 .../test-read-dwarf/test21-pr19092.so.abi     |  3232 +-
 .../test22-pr19097-libstdc++.so.6.0.17.so.abi | 59856 +++++-----------
 .../test8-qualified-this-pointer.so.abi       |    18 +-
 .../test8-qualified-this-pointer.so.hash.abi  |     6 -
 .../test9-pr18818-clang.so.abi                |  3052 +-
 tests/test-abicompat.cc                       |    13 +-
 tests/test-read-ctf.cc                        |     2 +-
 tests/test-symtab.cc                          |    48 +-
 tools/abicompat.cc                            |   558 +-
 91 files changed, 102720 insertions(+), 296210 deletions(-)
 create mode 100755 tests/data/test-abicompat/libtest6-undefined-var.so
 create mode 100644 tests/data/test-abicompat/test6-undefined-var.cc
 delete mode 100755 tests/data/test-abicompat/test6-var-changed-app
 delete mode 100644 tests/data/test-abicompat/test6-var-changed-app.cc
 create mode 100644 tests/data/test-abicompat/test6-var-changed-report-2.txt

[The patch is too big for the mailing list so I am attaching it in
gzipped form below].


[-- Attachment #2: 0001-Represent-undefined-corpus-interfaces-to-analyze-app.patch.gz --]
[-- Type: application/gzip, Size: 2537136 bytes --]

[-- Attachment #3: Type: text/plain, Size: 13 bytes --]


-- 
		Dodji

  reply	other threads:[~2024-03-14 17:01 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-14 16:54 [PATCH 0/4] Support undefined interfaces to fix abicompt's weak mode Dodji Seketeli
2024-03-14 16:57 ` Dodji Seketeli [this message]
2024-03-14 16:59 ` [PATCH 2/4] Factorize elf-reader::{variable,function}_symbol_is_exported into symtab Dodji Seketeli
2024-03-14 17:00 ` [PATCH 3/4] Add support for undefined symbols in the BTF reader Dodji Seketeli
2024-03-14 17:00 ` [PATCH 4/4] Emit & read undefined interfaces to & from ABIXML Dodji Seketeli

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