libabigail/tests/data/test-read-dwarf
Dodji Seketeli 635e5fa6b2 Delay non-complete class type resolution up to end of corpus reading
From the DWARF emitted by GCC 4.4.7 for libstdc++ we encountered an
interesting construct.

A non-complete version of std::runtime_error is declared in
libstdc++-v3/src/functexcept.cc and is represented in DWARF as:

     [ 37344]      class_type
		    name                 (strp) "runtime_error"
		    declaration          (flag)

Then a bit later, that *non-complete* class is used as a base class
for a class, *without* being fully defined!  This shouldn't happen
but, well, it does:

     [ 3b3a1]    class_type
		  specification        (ref4) [ 3733e]
		  byte_size            (data1) 16
		  decl_file            (data1) 5
		  decl_line (data1) 141
		  containing_type      (ref4) [ 3734a]
		  sibling              (ref4) [3b405]
     [ 3b3b1]      inheritance
		   type                 (ref4) [ 37344] <---- here.

The thing is that, later, in another translation unit
(libstdc++-v3/src/stdexcept.cc), that same class is defined fully:

     [ 7e9f9]      class_type
		   name                 (strp) "runtime_error"
		   declaration          (flag)
[...]

     [ 80c95]    class_type
		 specification        (ref4) [ 7e9f9]
		 byte_size            (data1) 16
		 decl_file            (data1) 4
		 decl_line            (data1) 108
		 containing_type      (ref4) [ 7e9ff]
		 sibling              (ref4) [ 80d2b]
		 [...] <---------- and the definition goes here.

But then you see that the DIE offset of the "version" of the
runtime_error class that is "defined" libstdc++-v3/src/stdexcept.cc in
is different from the version that is only declared in
libstdc++-v3/src/functexcept.cc.  But virtue of the "One Definition
Rule", we can assume that they designate the same type.  But still,
runtime_error should have been defined in
libstdc++-v3/src/stdexcept.cc.  Anyhow, libabigail needs to be able to
handle this.  That is, it needs to wait until the entire ABI corpus is
loaded from DWARF, then lookup the definition of all the non-complete
types we have encountered.

And then only after that non-complete type resolution has taken place,
we can proceed with type canonicalizing, rather than doing it after
the loading of each translation unit like what we were doing
previously.

This is what this patch does.

	* include/abg-fwd.h (lookup_type_in_corpus): Declare new function.
	* src/abg-corpus.cc (lookup_type_in_corpus): Define new function
	here.
	* include/abg-ir.h (function_types_type): Declare new typedef.
	(translation_unit::get_canonical_function_type): Remove member function.
	(translation_unit::bind_function_type_life_time): Declare new
	member function.
	(classes_type): New typedef.
	* src/abg-ir.cc
	(translation_unit::priv::canonical_function_types_): Remove data
	member.
	(translation_unit::priv::function_types): New data member.
	(translation_unit::get_canonical_function_type): Remove this
	function definition.
	(translation_unit::bind_function_type_life_time): New function
	definition.
	(lookup_node_in_scope): Ensure that the type returned is
	complete.
	* src/abg-dwarf-reader.cc (string_classes_map): New typedef.
	(read_context::decl_only_classes_map_): New data member.
	(read_context::declaration_only_classes): New accessor.
	(read_context::{maybe_schedule_declaration_only_class_for_resolution,
	is_decl_only_class_scheduled_for_resolution,
	resolve_declaration_only_classes, current_elf_file_is_executable,
	current_elf_file_is_dso}): Define new member functions.
	(read_context::clear_per_translation_unit_data): Do not clear the
	data structures that associate DIEs to decls/types or that contain
	the types to canonicalize here.  Rather, clear them ...
	(read_context::clear_per_corpus_data): ... here instead.
	(read_context::build_translation_unit_and_add_to_ir): Do not
	perform late type canonicalizing here.  Rather, do it ...
	(read_debug_info_into_corpus): ... here instead.  And before that,
	call read_context::clear_per_corpus_data() and the new
	read_context::resolve_declaration_only_classes() here.
	(build_class_type_and_add_to_ir): Schedule the non-complete types
	for resolution to complete types.  Assert that base classes that
	are non-complete are scheduled to be completed.
	(build_function_decl): Do not try to canonicalize function types
	this early, systematically.  Now, all the non-complete types needs
	to be completed before starting canonicalizing.  So let function
	types go through the normal processes of deciding when to
	canonicalize them.  But then, bind the life time of the function
	type to the life time of the current translation unit.
	(maybe_canonicalize_type): If a class type is non-complete,
	schedule it for late canonicalizing.
	* src/abg-hash.cc (class_decl:#️⃣:operator()(const class_decl&)
	const): During hashing, a base class should be complete.
	* src/abg-reader.cc
	(read_context::clear_per_translation_unit_data): Do not clear
	id/xml node, and type maps here.  Rather, clear it ...
	(read_context::clear_per_corpus_data): ... here instead.
	(read_translation_unit_from_input): Do not perform late
	canonicalizing here.  Rather, do it ...
	(read_corpus_from_input): ... here.  Also, call the new
	read_context::clear_per_corpus_data() here.
	(build_function_decl): Do not canonicalize function types here so
	early.  Rather, bind the life time of the function type to the
	life time of the translation unit.
	* src/abg-writer.cc (write_translation_unit): Do not clear the
	type/ID map here.
	* tests/data/test-read-dwarf/test2.so.abi: Adjust test input.

Signed-off-by: Dodji Seketeli <dodji@redhat.com>
2015-03-17 10:54:12 +01:00
..
test0 Tweak dwarf reading test to detect more namespace linking-fu 2014-01-13 17:36:20 +01:00
test0.abi Support reading and comparing soname from ELF files 2014-12-07 23:42:26 +01:00
test0.cc Tweak dwarf reading test to detect more namespace linking-fu 2014-01-13 17:36:20 +01:00
test1
test1.abi Support reading and comparing soname from ELF files 2014-12-07 23:42:26 +01:00
test1.cc
test2-0.cc Initial support for DW_TAG_partial_unit 2014-05-19 17:26:40 +02:00
test2-1.cc Initial support for DW_TAG_partial_unit 2014-05-19 17:26:40 +02:00
test2.h Initial support for DW_TAG_partial_unit 2014-05-19 17:26:40 +02:00
test2.so Initial support for DW_TAG_partial_unit 2014-05-19 17:26:40 +02:00
test2.so.abi Delay non-complete class type resolution up to end of corpus reading 2015-03-17 10:54:12 +01:00
test3.c Keep symbol's multiple aliases within single attribute separated by comma 2014-06-20 11:56:49 +02:00
test3.so Keep symbol's multiple aliases within single attribute separated by comma 2014-06-20 11:56:49 +02:00
test3.so.abi Support reading and comparing soname from ELF files 2014-12-07 23:42:26 +01:00
test4.c Handle C99 restrict qualifier and DWARFv3 DW_TAG_restrict_type. 2014-06-23 15:55:37 +02:00
test4.so Handle C99 restrict qualifier and DWARFv3 DW_TAG_restrict_type. 2014-06-23 15:55:37 +02:00
test4.so.abi Support reading and comparing soname from ELF files 2014-12-07 23:42:26 +01:00
test5.cc Support reading void* type from DWARF 2014-06-23 17:31:26 +02:00
test5.o Support reading void* type from DWARF 2014-06-23 17:31:26 +02:00
test5.o.abi Support reading void* type from DWARF 2014-06-23 17:31:26 +02:00
test6.cc Consider symbols with STB_GNU_UNIQUE binding as public 2014-07-08 14:18:36 +02:00
test6.so Consider symbols with STB_GNU_UNIQUE binding as public 2014-07-08 14:18:36 +02:00
test6.so.abi Support reading and comparing soname from ELF files 2014-12-07 23:42:26 +01:00
test7.cc Support C and C++ array type. 2014-08-22 13:07:41 +02:00
test7.so Support C and C++ array type. 2014-08-22 13:07:41 +02:00
test7.so.abi Support C and C++ array type. 2014-08-22 13:07:41 +02:00
test8-qualified-this-pointer.cc Yet another fix to the DWARF method "static-ness" detection heuristic 2014-10-16 23:49:41 +02:00
test8-qualified-this-pointer.so Yet another fix to the DWARF method "static-ness" detection heuristic 2014-10-16 23:49:41 +02:00
test8-qualified-this-pointer.so.abi Support reading and comparing soname from ELF files 2014-12-07 23:42:26 +01:00