Commit Graph

101536 Commits

Author SHA1 Message Date
Nick Clifton
714e6c969f GAS: Allow automatically assigned entries in the file table to be reassigned if the source file specifically requests to use the assigned slot.
PR 25878
	* dwarf2dbg.c (struct file_entry): Add auto_assigned field.
	(assign_file_to_slot): New function.  Fills in an entry in the
	files table.
	(allocate_filenum): Use new function.
	(allocate_filename_to_slot): Use new function.  If the specified
	slot entry is already in use, but was chosen automatically then
	reassign the automatic entry.
2020-04-27 11:35:25 +01:00
GDB Administrator
25e29062d2 Automatic date update in version.in 2020-04-27 00:00:15 +00:00
Tom Tromey
361ba0e891 Remove class_pseudo
The class_pseudo constant is unused, so this removes it.
Tested by rebuilding.

gdb/ChangeLog
2020-04-26  Tom Tromey  <tom@tromey.com>

	* command.h (enum command_class) <class_pseudo>: Remove.
2020-04-26 13:48:11 -06:00
Alan Modra
90837ea721 readelf: NULL dereference
This fixes another missing error check.

	* readelf.c (get_num_dynamic_syms): Check DT_MIPS_XHASH was
	read before dereferencing, and gracefully return.  Remove
	gnu_hash_error variable.  Free gnu hash arrays if number of
	syms found is zero.
2020-04-26 23:50:18 +09:30
Philippe Waroquiers
bc3609fd38 Fix comments and whitespace in lookup_cmd_composition
2020-04-26  Philippe Waroquiers  <philippe.waroquiers@skynet.be>

	* cli/cli-decode.c (lookup_cmd_composition): Fix comments
	and whitespace.
2020-04-26 16:05:41 +02:00
liuhongt
a09f656b26 Improve -mlfence-after-load
1.Implict load for POP/POPF/POPA/XLATB, no load for Anysize insns
  2. Add -mlfence-before-ret=shl/yes, adjust operand size of
  or/not/shl according to ret's.
  3. Issue warning for REP CMPS/SCAS since they would affect control
  flow behavior.
  4. Adjust testcases and documents.

gas/Changelog:
	* config/tc-i386.c (lfence_before_ret_shl): New member.
	(load_insn_p): implict load for POP/POPA/POPF/XLATB, no load
	for Anysize insns.
	(insert_after_load): Issue warning for REP CMPS/SCAS.
	(insert_before_before): Handle iret, Handle
	-mlfence-before-ret=shl, Adjust operand size of or/not/shl to ret's,
	(md_parse_option): Change -mlfence-before-ret=[none|not|or] to
	-mlfence-before-ret=[none/not/or/shl/yes].
	Enable -mlfence-before-ret=shl when
	-mlfence-beofre-indirect-branch=all and no explict -mlfence-before-ret option.
	(md_show_usage): Ditto.
	* doc/c-i386.texi: Ditto.
	* testsuite/gas/i386/i386.exp: Add new testcases.
	* testsuite/gas/i386/lfence-load-b.d: New.
	* testsuite/gas/i386/lfence-load-b.e: New.
	* testsuite/gas/i386/lfence-load.d: Modified.
	* testsuite/gas/i386/lfence-load.e: New.
	* testsuite/gas/i386/lfence-load.s: Modified.
	* testsuite/gas/i386/lfence-ret-a.d: Modified.
	* testsuite/gas/i386/lfence-ret-b.d: Modified.
	* testsuite/gas/i386/lfence-ret-c.d: New.
	* testsuite/gas/i386/lfence-ret-d.d: New.
	* testsuite/gas/i386/lfence-ret.s: Modified.
	* testsuite/gas/i386/x86-64-lfence-load-b.d: New.
	* testsuite/gas/i386/x86-64-lfence-load.d: Modified.
	* testsuite/gas/i386/x86-64-lfence-load.s: Modified.
	* testsuite/gas/i386/x86-64-lfence-ret-a.d: Modified.
	* testsuite/gas/i386/x86-64-lfence-ret-b.d: Modified.
	* testsuite/gas/i386/x86-64-lfence-ret-c.d: New.
	* testsuite/gas/i386/x86-64-lfence-ret-d.d: New
	* testsuite/gas/i386/x86-64-lfence-ret-e.d: New.
	* testsuite/gas/i386/x86-64-lfence-ret.e: New.
	* testsuite/gas/i386/x86-64-lfence-ret.s: New.
2020-04-26 14:26:24 +08:00
GDB Administrator
ec9c4d8322 Automatic date update in version.in 2020-04-26 00:00:07 +00:00
Kamil Rytarowski
b9771db784 Remove unused code block in inf_ptrace_target::wait
Remove unused PT_GET_PROCESS_STATE block. It used to be used
by OpenBSD, but it is now reimplemented independently in
obsd-nat.c.

gdb/ChangeLog:

       * inf-ptrace.c (inf_ptrace_target::wait): Remove
       `PT_GET_PROCESS_STATE' block.

Change-Id: I9b872df8517b658c0dfe889fc1e4a7009bc5c076
2020-04-25 17:24:51 -05:00
Tom de Vries
d472f0fbaa [gdb/testsuite] Add target board debug-types
This patch adds a target board debug-types that switches on
-fdebug-types-section by default.

This -fdebug-types-section option is a gcc option that enables the generation
of a .debug_types section, which is only effective for DWARF version 4.

There are two other boards that enable this: dwarf4-gdb-index and fisson, but
while those test some meaningful combination of options, this board is
intended to test only -fdebug-types-section.

Current results with gcc 7.5.0 are:
...
 === gdb Summary ===

 # of expected passes            75832
 # of unexpected failures        2841
 # of expected failures          130
 # of known failures             75
 # of unresolved testcases       22
 # of untested testcases         37
 # of unsupported tests          83
...

Related known issues:
- PR gcc/90232 - "gcc drops top-level dies with -fdebug-types-section"
- PR gdb/25875 - "segv in ada_discrete_type_low_bound"
- PR gdb/14148 - "-fdebug-types-section regresses static scope of types"

Tested on x86_64-linux.

gdb/testsuite/ChangeLog:

2020-04-25  Tom de Vries  <tdevries@suse.de>

	* boards/debug-types.exp: New file.
2020-04-25 17:19:26 +02:00
Andrew Burgess
8d840e05dc gdb/testsuite: Remove build paths from test names
Having paths in test names makes it harder to compare results from
different builds of GDB.

gdb/testsuite/ChangeLog:

	* gdb.btrace/multi-inferior.exp: Avoid paths in test names.
2020-04-25 10:29:27 +01:00
GDB Administrator
617769d62f Automatic date update in version.in 2020-04-25 00:00:08 +00:00
Tom Tromey
7151c1af38 Remove symbol_get_demangled_name
Now that symbol_get_demangled_name is only used by general_symbol_info
methods, and because these methods already check the symbol's language
to decide what to return, symbol_get_demangled_name is no longer
needed.  This patch removes it.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tom@tromey.com>

	* symtab.h (symbol_get_demangled_name): Don't declare.
	* symtab.c (symbol_get_demangled_name): Remove.
	(general_symbol_info::natural_name)
	(general_symbol_info::demangled_name): Update.
2020-04-24 15:35:04 -06:00
Tom Tromey
906bb4c58f Fix Rust test cases
PR rust/25025 notes that some Rust test cases fail.

Debugging gdb revealed that the Rust compiler emits different linkage
names that demangle to the same result.  Enabling complaints when
reading the test case is enough to show it:

    During symbol reading: Computed physname <generics::identity<f64>> does not match demangled <generics::identity> (from linkage <_ZN8generics8identity17h8540b320af6656d6E>) - DIE at 0x424 [in module /home/tromey/gdb/build/gdb/testsuite/outputs/gdb.rust/generics/generics]
    During symbol reading: Computed physname <generics::identity<u32>> does not match demangled <generics::identity> (from linkage <_ZN8generics8identity17hae302fad0c33bd7dE>) - DIE at 0x459 [in module /home/tromey/gdb/build/gdb/testsuite/outputs/gdb.rust/generics/generics]
    ...

This patch changes the DWARF reader to prefer the computed physname,
rather than the output of the demangler, for Rust.  This fixes the
bug.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tom@tromey.com>

	PR rust/25025:
	* dwarf2/read.c (dwarf2_physname): Do not demangle for Rust.
2020-04-24 15:35:03 -06:00
Tom Tromey
bcfe6157ca Use the linkage name if it exists
The DWARF reader has had some odd code since the "physname" patches landed.

In particular, these patches caused PR symtab/12707; namely, they made
it so "set print demangle off" no longer works.

This patch attempts to fix the problem.  It arranges to store the
linkage name on the symbol if it exists, and it changes the DWARF
reader so that the demangled name is no longer (usually) stored in the
symbol's "linkage name" field.

c-linkage-name.exp needed a tweak, because it started working
correctly.  This conforms to what I think ought to happen, so this
seems like an improvement here.

compile-object-load.c needed a small change to use
symbol_matches_search_name rather than directly examining the linkage
name.  Looking directly at the name does the wrong thing for C++.

There is still some name-related confusion in the DWARF reader:

* "physname" often refers to the logical name and not what I would
  consider to be the "physical" name;

* dwarf2_full_name, dwarf2_name, and dwarf2_physname all exist and
  return different strings -- but this seems like at least one name
  too many.  For example, Fortran requires dwarf2_full_name, but other
  languages do not.

* To my surprise, dwarf2_physname prefers the form emitted by the
  demangler over the one that it computes.  This seems backward to me,
  given that the partial symbol reader prefers the opposite, and it
  seems to me that this choice may perform better as well.

I didn't attempt to clean up these things.  It would be good to do,
but whenever I contemplate it I get caught up in dreams of truly
rewriting the DWARF reader instead.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tom@tromey.com>

	PR symtab/12707:
	* dwarf2/read.c (add_partial_symbol): Use the linkage name if it
	exists.
	(new_symbol): Likewise.
	* compile/compile-object-load.c (get_out_value_type): Use
	symbol_matches_search_name.

gdb/testsuite/ChangeLog
2020-04-24  Tom Tromey  <tom@tromey.com>

	PR symtab/12707:
	* gdb.python/py-symbol.exp: Update expected results for
	linkage_name test.
	* gdb.cp/print-demangle.exp: New file.
	* gdb.base/c-linkage-name.exp: Fix test.
	* gdb.guile/scm-symbol.exp: Update expected results for
	linkage_name test.
2020-04-24 15:35:03 -06:00
Tom Tromey
f049a313fc Don't call compute_and_set_names for partial symbols
As mentioned in another thread, there's currently no need to call
compute_and_set_names for partial symbols.  Because the DWARF partial
symbol reader constructs demangled names, this call can only demangle
a name by mistake.

So, this patch changes the DWARF reader to simply set the linkage name
on the new symbol.  This is equivalent to what was done before.  There
should be no user-visible change from this patch, aside from gdb
speeding up a bit.

... there *should* be, but this regressed
dw2-namespaceless-anonymous.exp.  However, upon examination, I think
that test is incorrect.  It puts a mangled name into DW_AT_name, and
it puts the variable at the top level, not in a namespace.  This isn't
what C++ compilers ought to do.  So, this patch also updates the test
case.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tom@tromey.com>

	* dwarf2/read.c (add_partial_symbol): Do not call
	compute_and_set_names.

gdb/testsuite/ChangeLog
2020-04-24  Tom Tromey  <tom@tromey.com>

	* gdb.dwarf2/dw2-namespaceless-anonymous.S: Remove.
	* gdb.dwarf2/dw2-namespaceless-anonymous.c: New file.
	* gdb.dwarf2/dw2-namespaceless-anonymous.exp: Use DWARF
	assembler.
2020-04-24 15:35:03 -06:00
Tom Tromey
76e288d1d2 Use the new add_psymbol_to_list overload
This changes the DWARF reader to use the new add_psymbol_to_list
overload.  There should be no visible changes due to this patch.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tom@tromey.com>

	* dwarf2/read.c (add_partial_symbol): Use new add_psymbol_to_list
	overload.
2020-04-24 15:35:03 -06:00
Tom Tromey
2467f4f6a5 Introduce new add_psymbol_to_list overload
This adds a new overload of add_psymbol_to_list.  This one takes an
already constructed psymbol and adds it to the bcache and the
appropriate list.

This seemed cleaner than continuing to add parameters to the existing
add_psymbol_to_list, and is more in line with how full symbols are
constructed.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tom@tromey.com>

	* psymtab.c (add_psymbol_to_bcache): Simplify calling convention.
	(add_psymbol_to_list): New overload.  Make old overload call new
	one.
	* psympriv.h (add_psymbol_to_list): New overload.
2020-04-24 15:35:02 -06:00
Tom Tromey
e61108c92d Add attribute::value_as_string method
The full DIE reader checks that an attribute has a "string" form in
some spots, but the partial DIE reader does not.  This patch brings
the two readers in sync for one specific case, namely when examining
the linkage name.  This avoids regressions in an existing DWARF test
case.

A full fix for this problem would be preferable.  An accessor like
DW_STRING should always check the form.  However, I haven't attempted
that in this series.

Also the fact that the partial and full readers can disagree like this
is a design flaw.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tom@tromey.com>

	* dwarf2/read.c (partial_die_info::read) <case
	DW_AT_linkage_name>: Use value_as_string.
	(dwarf2_string_attr): Use value_as_string.
	* dwarf2/attribute.h (struct attribute) <value_as_string>: Declare
	method.
	* dwarf2/attribute.c (attribute::value_as_string): New method.
2020-04-24 15:35:02 -06:00
Tom Tromey
8c87a4527f Fix two latent Rust bugs
Two methods on general_symbol_info did not handle the language_rust
case.  I don't think these problems can be noticed with the current
code (which is why the bugs went unnoticed), but a future patch will
change this.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tom@tromey.com>

	* symtab.c (general_symbol_info::natural_name)
	(general_symbol_info::demangled_name): Check for language_rust.
2020-04-24 15:35:02 -06:00
Tom Tromey
787de330ee Move the rust "{" hack
The DWARF reader has a special case to work around a bug in some
versions of the Rust compiler -- it ignores mangled names that contain
a "{" character.

I noticed that this check should probably be in dw2_linkage_name
rather than only in dwarf2_physname.  The former is called in some
cases that the latter is not.

Also, I noticed that this work is not done for the partial DIE reader,
so this patch adds the check there as well.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tom@tromey.com>

	* dwarf2/read.c (dw2_linkage_name): Move Rust "{" hack here...
	(dwarf2_physname): ... from here.
	(partial_die_info::read): Add Rust "{" hack.
2020-04-24 15:35:02 -06:00
Tom Tromey
ff98567107 Convert symbol_set_demangled_name to a method
This changes symbol_set_demangled_name to be a method on
general_symbol_info, and updates the users.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tom@tromey.com>

	* symtab.h (struct general_symbol_info) <set_demangled_name>: New
	method.
	(symbol_set_demangled_name): Don't declare.
	* symtab.c (general_symbol_info::set_demangled_name): Rename from
	symbol_set_demangled_name.
	(general_symbol_info::set_language)
	(general_symbol_info::compute_and_set_names): Update.
	* minsyms.c (minimal_symbol_reader::install): Update.
	* dwarf2/read.c (new_symbol): Update.
2020-04-24 15:35:02 -06:00
Tom de Vries
7cf288744f [gdb/testsuite] Fix language in dw2-bad-mips-linkage-name.exp
The test-case gdb.dwarf2/dw2-bad-mips-linkage-name.exp has a CU with
language C, which contains a subprogram with a C++-mangled name as its
DW_AT_mips_linkage_name attribute.

Fix this by changing the language of the CU to C++.

Tested on x86_64-linux.

gdb/testsuite/ChangeLog:

2020-04-24  Tom de Vries  <tdevries@suse.de>

	* gdb.dwarf2/dw2-bad-mips-linkage-name.exp: Set language of CU to
	C++.
2020-04-24 23:25:44 +02:00
Tom Tromey
dac2fef7cf Update test cases that work with minimal encodings
Some test cases already work fine with minimal encodings (in some
cases perhaps due to the variant parts series) This patch updates
these tests as appropriate.

gdb/testsuite/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* gdb.ada/frame_arg_lang.exp: Run with multiple -fgnat-encodings
	values.
	* gdb.ada/funcall_ref.exp: Run with multiple -fgnat-encodings
	values.  Update test for minimal encodings.
	* gdb.ada/lang_switch.exp: Update test for minimal encodings.
	* gdb.ada/var_rec_arr.exp: Run with multiple -fgnat-encodings
	values.  Update test for minimal encodings.
2020-04-24 13:40:33 -06:00
Tom Tromey
1acda8039b Add Python support for dynamic types
This changes the gdb Python API to add support for dynamic types.  In
particular, this adds an attribute to gdb.Type, and updates some
attributes to reflect dynamic sizes and field offsets.

There's still no way to get the dynamic type from one of its concrete
instances.  This could perhaps be added if needed.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	PR python/23662:
	* python/py-type.c (convert_field): Handle
	FIELD_LOC_KIND_DWARF_BLOCK.
	(typy_get_sizeof): Handle TYPE_HAS_DYNAMIC_LENGTH.
	(typy_get_dynamic): Nw function.
	(type_object_getset): Add "dynamic".
	* NEWS: Add entry.

gdb/doc/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	PR python/23662:
	* python.texi (Types In Python): Document new features.

gdb/testsuite/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	PR python/23662:
	* gdb.ada/variant.exp: Add Python checks.
	* gdb.rust/simple.exp: Add dynamic type checks.
2020-04-24 13:40:33 -06:00
Tom Tromey
adfb981595 Add tests for Ada changes
The previous patches largely came without test cases.  This was done
to make the patches easier to review; as most of the patches were
needed before existing tests could be updated.

This patch adds a new test and updates some existing tests to test all
the settings of -fgnat-encodings.  This ensures that tests are run
both with the old-style "magic symbol name" encoding, and the
new-style DWARF encoding.

Note that in one case, a test is modified to be more lax.  See the
comment in mi_var_array.exp.  I didn't want to fix this in this
series, as it's already complicated enough.  However, I think it could
be fixed; I will file a bug for it.

gdb/testsuite/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* gdb.ada/mi_var_array.exp: Try all -fgnat-encodings settings.
	Make array type matching more lax.
	* gdb.ada/mi_var_union.exp: Try all -fgnat-encodings settings.
	* gdb.ada/mi_variant.exp: New file.
	* gdb.ada/mi_variant/pck.ads: New file.
	* gdb.ada/mi_variant/pkg.adb: New file.
	* gdb.ada/packed_tagged.exp: Try all -fgnat-encodings settings.
	* gdb.ada/unchecked_union.exp: Try all -fgnat-encodings settings.
2020-04-24 13:40:33 -06:00
Tom Tromey
d656f129eb Update Ada ptype support for dynamic types
The DWARF reader was updated to handle variant parts and some other
selected features for Ada; but the Ada "ptype" code was not touched.
This patch changes the Ada ptype code to handle the new types
properly.

Test cases for this and for some of the other code in this series are
in a separate patch.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* ada-typeprint.c (print_choices, print_variant_part)
	(print_record_field_types_dynamic): New functions.
	(print_record_field_types): Use print_record_field_types_dynamic.
2020-04-24 13:40:32 -06:00
Tom Tromey
7d79de9a4b Add support for variable field offsets
In Ada, a field can have a variable offset.  This patch adds support
for this case to gdb, using the existing dynamic type resolution code.

Doing just this, though, would break C++ virtual base handling.

It turns out that virtual base handling only worked by the ugliest of
hacks.  In particular, the DWARF reader would call decode_locdesc for
a virtual base location.  Here's an example of such an expression from
gdb's m-static test case:

    <241>   DW_AT_data_member_location: 6 byte block: 12 6 48 1c 6 22 	(DW_OP_dup; DW_OP_deref; DW_OP_lit24; DW_OP_minus; DW_OP_deref; DW_OP_plus)

When examining this, decode_locdesc would treat DW_OP_deref as a no-op
and compute some answer (here, -24).  This would be stored as the
offset.

Later, in gnu-v3-abi.c, the real offset would be computed by digging
around in the vtable.

This patch cleans up this area.  In particular, it now evaluates the
location expression on demand.

Note there is a new FIXME in gnu-v3-abi.c.  I think some of the
callers are incorrect here, and have only worked because this member
is unused.  I will file a bug for this.  I didn't fix this problem in
this series because I felt it was already too complex.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* dwarf2/read.c (handle_data_member_location): New overload.
	(dwarf2_add_field): Use it.
	(decode_locdesc): Add "computed" parameter.  Update comment.
	* gdbtypes.c (is_dynamic_type_internal): Also look for
	FIELD_LOC_KIND_DWARF_BLOCK.
	(resolve_dynamic_struct): Handle FIELD_LOC_KIND_DWARF_BLOCK.
	* gdbtypes.c (is_dynamic_type_internal): Add special case for C++
	virtual base classes.
	* gnu-v3-abi.c (gnuv3_baseclass_offset): Handle
	FIELD_LOC_KIND_DWARF_BLOCK.

gdb/testsuite/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* gdb.ada/variant.exp: Add dynamic field offset tests.
	* gdb.ada/variant/pck.ads (Nested_And_Variable): New type.
	* gdb.ada/variant/pkg.adb: Add new variables.
2020-04-24 13:40:32 -06:00
Tom Tromey
f8e89861cf Add support for dynamic type lengths
In Ada, a type with variant parts can have a variable length.  This
patch adds support for this to gdb, by integrating the length
computation into the dynamic type resolution code.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* dwarf2/read.c (read_structure_type): Handle dynamic length.
	* gdbtypes.c (is_dynamic_type_internal): Check
	TYPE_HAS_DYNAMIC_LENGTH.
	(resolve_dynamic_type_internal): Use TYPE_DYNAMIC_LENGTH.
	* gdbtypes.h (TYPE_HAS_DYNAMIC_LENGTH, TYPE_DYNAMIC_LENGTH):
	New macros.
	(enum dynamic_prop_node_kind) <DYN_PROP_BYTE_SIZE>: New
	constant.

gdb/testsuite/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* gdb.ada/variant.exp: New file
	* gdb.ada/variant/pkg.adb: New file
	* gdb.ada/variant/pck.adb: New file
2020-04-24 13:40:32 -06:00
Tom Tromey
9c6a1327ad Rewrite the existing variant part code
This rewrites the existing variant part code to follow the new model
implemented in the previous patch.  The old variant part code is
removed.

This only affects Rust for the moment.  I tested this using various
version of the Rust compiler, including one that emits old-style enum
debuginfo, exercising the quirks code.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* dwarf2/read.c (struct variant_field): Rewrite.
	(struct variant_part_builder): New.
	(struct nextfield): Remove "variant" field.  Add "offset".
	(struct field_info): Add "current_variant_part" and
	"variant_parts".
	(alloc_discriminant_info): Remove.
	(alloc_rust_variant): New function.
	(quirk_rust_enum): Update.
	(dwarf2_add_field): Set "offset" member.  Don't handle
	DW_TAG_variant_part.
	(offset_map_type): New typedef.
	(convert_variant_range, create_one_variant)
	(create_one_variant_part, create_variant_parts)
	(add_variant_property): New functions.
	(dwarf2_attach_fields_to_type): Call add_variant_property.
	(read_structure_type): Don't handle DW_TAG_variant_part.
	(handle_variant_part, handle_variant): New functions.
	(handle_struct_member_die): Use them.
	(process_structure_scope): Don't handle variant parts.
	* gdbtypes.h (TYPE_FLAG_DISCRIMINATED_UNION): Remove.
	(struct discriminant_info): Remove.
	(enum dynamic_prop_node_kind) <DYN_PROP_DISCRIMINATED>: Remove.
	(struct main_type) <flag_discriminated_union>: Remove.
	* rust-lang.c (rust_enum_p, rust_empty_enum_p): Rewrite.
	(rust_enum_variant): Return int.  Remove "contents".  Rewrite.
	(rust_print_enum, rust_print_struct_def, rust_evaluate_subexp):
	Update.
	* valops.c (value_union_variant): Remove.
	* value.h (value_union_variant): Don't declare.
2020-04-24 13:40:32 -06:00
Tom Tromey
b249d2c2c0 Prefer existing data when evaluating DWARF expression
When evaluating a DWARF expression, the dynamic type resolution code
will pass in a buffer of bytes via the property_addr_info.  However,
the DWARF expression evaluator will then proceed to read memory from
the inferior, even when the request could be filled from this buffer.

This, in turn, is a problem in some cases; and specifically when
trying to handle the Ada scenario of extracting a variable-length
value from a packed array.  Here, the ordinary DWARF expression cannot
be directly evaluated, because the data may appear at some arbitrary
bit offset.  So, it is unpacked into a staging area and then the
expression is evaluated -- using an address of 0.

This patch fixes the problem by arranging for the DWARF evaluator, in
this case, to prefer passed-in memory when possible.  The type of the
buffer in the property_addr_info is changed to an array_view so that
bounds checking can be done.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* ada-lang.c (ada_discrete_type_high_bound, ada_discrete_type_low)
	(ada_value_primitive_packed_val): Update.
	* ada-valprint.c (ada_value_print_1): Update.
	* dwarf2/loc.c (evaluate_for_locexpr_baton): New struct.
	(dwarf2_locexpr_baton_eval): Take a property_addr_info rather than
	just an address.  Use evaluate_for_locexpr_baton.
	(dwarf2_evaluate_property): Update.
	* dwarf2/loc.h (struct property_addr_info) <valaddr>: Now an
	array_view.
	* findvar.c (default_read_var_value): Update.
	* gdbtypes.c (compute_variant_fields_inner)
	(resolve_dynamic_type_internal): Update.
	(resolve_dynamic_type): Change type of valaddr parameter.
	* gdbtypes.h (resolve_dynamic_type): Update.
	* valarith.c (value_subscripted_rvalue): Update.
	* value.c (value_from_contents_and_address): Update.
2020-04-24 13:40:31 -06:00
Tom Tromey
61122aa9ed Allow DWARF expression to push the initial address
Some DWARF expressions must be evaluated by first pushing the object
address onto the evaluation stack.  This patch adds this ability.
This functionality is not used yet, but it will be used in a later
patch.  This is split out for easier review and also because it
improved the patch series ordering.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* dwarf2/loc.c (dwarf2_locexpr_baton_eval): Add
	"push_initial_value" parameter.
	(dwarf2_evaluate_property): Likewise.
	* dwarf2/loc.h (dwarf2_evaluate_property): Update.
2020-04-24 13:40:31 -06:00
Tom Tromey
ef83a141a2 Add new variant part code
This patch adds the infrastructure for the new variant part code.  At
this point, nothing uses this code.  This is done in a separate patch
to make it simpler to review.

I examined a few possible approaches to handling variant parts.  In
particular, I considered having a DWARF variant part be a union
(similar to how the Rust code works now); and I considered having type
fields have a flag indicating that they are variants.

Having separate types seemed bad conceptually, because these variants
aren't truly separate -- they rely on the "parent" type.  And,
changing how fields worked seemed excessively invasive.

So, in the end I thought the approach taken in this patch was both
simple to implement and understand, without losing generality.  The
idea in this patch is that all the fields of a type with variant parts
will be stored in a single field array, just as if they'd all been
listed directly.  Then, the variants are attached as a dynamic
property.  These control which fields end up in the type that's
constructed during dynamic type resolution.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* gdbtypes.c (is_dynamic_type_internal): Check for variant parts.
	(variant::matches, compute_variant_fields_recurse)
	(compute_variant_fields_inner, compute_variant_fields): New
	functions.
	(resolve_dynamic_struct): Check for DYN_PROP_VARIANT_PARTS.
	Use resolved_type after type is made.
	(operator==): Add new cases.
	* gdbtypes.h (TYPE_HAS_VARIANT_PARTS): New macro.
	(struct discriminant_range, struct variant, struct variant_part):
	New.
	(union dynamic_prop_data) <variant_parts, original_type>: New
	members.
	(enum dynamic_prop_node_kind) <DYN_PROP_VARIANT_PARTS>: New constant.
	(enum dynamic_prop_kind) <PROP_TYPE, PROP_VARIANT_PARTS>: New
	constants.
	* value.c (unpack_bits_as_long): Now public.
	* value.h (unpack_bits_as_long): Declare.
2020-04-24 13:40:31 -06:00
Tom Tromey
675127ec64 Rename "variant" to "ppc_variant"
I wanted to use the name "variant" to represent a DWARF variant, but
it turned out there was an existing structure of that name.  This
renames the existing variant to "ppc_variant".

gdb/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* rs6000-tdep.c (struct ppc_variant): Rename from "variant".
	(variants, find_variant_by_arch, rs6000_gdbarch_init): Update.
2020-04-24 13:40:31 -06:00
Hannes Domani
9852ceef7f Add WOW64 exception numbers to $_siginfo.ExceptionCode enum
gdb/ChangeLog:

2020-04-24  Hannes Domani  <ssbssa@yahoo.de>

	* windows-tdep.c (exception_values): Add WOW64 exception numbers.
2020-04-24 18:55:28 +02:00
Kamil Rytarowski
7632c6ce2b Move OpenBSD-only functions from inf-ptrace to obsd-nat
All major BSDs implement PT_GET_PROCESS_STATE, but they differ in
details and want to implement follow-fork functionality differently.

gdb/ChangeLog:

	* inf-ptrace.h (follow_fork, insert_fork_catchpoint)
	(remove_fork_catchpoint, post_startup_inferior)
	(post_attach): Move...
	* obsd-nat.h (follow_fork, insert_fork_catchpoint)
	(remove_fork_catchpoint, post_startup_inferior)
	(post_attach): ...here.
	* inf-ptrace.c (follow_fork, insert_fork_catchpoint)
	(remove_fork_catchpoint, post_startup_inferior)
	(post_attach): Move...
	* obsd-nat.c (follow_fork, insert_fork_catchpoint)
	(remove_fork_catchpoint, post_startup_inferior)
	(post_attach): ...here.
2020-04-24 17:46:36 +02:00
Tom de Vries
86e887ae11 [gdb/testsuite] Reset errcnt in clean_restart
When running test-case gdb.base/readnever.exp without commit 96038148d0
"[gdb/testsuite] Skip gdb.base/readnever.exp with target board readnow", we
run into an error:
...
ERROR: (eof) GDB never initialized.
testcase gdb/testsuite/gdb.base/readnever.exp completed in 0 seconds
...

If we additionally run test-case gdb.base/realname-expand.exp, we get an
unresolved for the first test:
...
UNRESOLVED: gdb.base/realname-expand.exp: set basenames-may-differ on
...

Using -v we find out that the UNRESOLVED is due the error triggered in the
previous test-case:
...
(gdb) set basenames-may-differ on^M
(gdb) Error/Warning threshold exceeded:  1 0 (max. 1 3)
UNRESOLVED: gdb.base/realname-expand.exp: set basenames-may-differ on
...

So, the error count of one test spills into the next test, even though we do a
clean restart.  That seems like a bad idea.

Fix this by resetting errcnt (as well as warncnt) in clean_restart, such that
we have:
...
Running src/gdb/testsuite/gdb.base/readnever.exp ...
ERROR: (eof) GDB never initialized.
Running src/gdb/testsuite/gdb.base/realname-expand.exp ...
PASS: gdb.base/realname-expand.exp: set basenames-may-differ on
...

Tested on x86_64-linux.

gdb/testsuite/ChangeLog:

2020-04-24  Tom de Vries  <tdevries@suse.de>

	* lib/gdb.exp (clean_restart): Reset errcnt and warncnt.
2020-04-24 16:21:30 +02:00
Tom Tromey
7be2bb4f47 Fix Windows debugging regression
The updated pending stop series introduced a regression in Windows
debugging.  When stopped at a software breakpoint, we would adjust the
PC each time it was requested -- however, more than a single
adjustment is incorrect.  This patch introduces a new flag that is
used to ensure the adjustment only happens a single time.

No similar change is needed in gdbserver, because it adjusts the PC in
a different way.

I still can't run the gdb test suite on Windows, but I can run the
internal AdaCore test suite there; and this fixes the regressions
there.

gdb/ChangeLog
2020-04-24  Tom Tromey  <tromey@adacore.com>

	* nat/windows-nat.h (struct windows_thread_info)
	<pc_adjusted>: New member.
	* windows-nat.c (windows_fetch_one_register): Check
	pc_adjusted.
	(windows_nat_target::get_windows_debug_event)
	(windows_nat_target::wait): Set pc_adjusted.
2020-04-24 06:48:01 -06:00
Tom de Vries
884287754e [gdb/testsuite] Compile dwzbuildid-mismatch more quietly
When running test-case gdb.dwarf2/dwzbuildid.exp with target board
cc-with-gdb-index, we have:
...
Running src/gdb/testsuite/gdb.dwarf2/dwzbuildid.exp ...
gdb compile failed, warning: File "dwzbuildid5.o" has a different \
  build-id, file skipped
could not find '.gnu_debugaltlink' file for dwzbuildid-mismatch
warning: File "dwzbuildid5.o" has a different build-id, file skipped
Error while writing index for `dwzbuildid-mismatch': could not find \
  '.gnu_debugaltlink' file for dwzbuildid-mismatch
...
and likewise for target board cc-with-debug-names.

These are gdb-add-index warnings and errors due to the executable
dwzbuildid-mismatch having a build-id mismatch.

Be less verbose by adding "quiet" to the compile flags.

Tested on x86_64-linux.

gdb/testsuite/ChangeLog:

2020-04-24  Tom de Vries  <tdevries@suse.de>

	* gdb.dwarf2/dwzbuildid.exp: Add quiet to dwzbuildid-mismatch compile
	flags.
2020-04-24 13:59:42 +02:00
Tom de Vries
4e86f6e747 [gdb/testsuite] Compile gdb.dwarf2/dw2-error.exp quietly
When running test-case gdb.dwarf2/dw2-error.exp with target board
cc-with-gdb-index, we get:
...
Running src/gdb/testsuite/gdb.dwarf2/dw2-error.exp ...
gdb compile failed, Dwarf Error: wrong version in compilation unit header \
  (is 153, should be 2, 3, 4 or 5) [in module \
  build/gdb/testsuite/outputs/gdb.dwarf2/dw2-error/.tmp/dw2-error]
...
and similar for target board cc-with-debug-names.

Be less verbose by adding "quiet" to the compile flags.

Tested on x86_64-linux.

gdb/testsuite/ChangeLog:

2020-04-24  Tom de Vries  <tdevries@suse.de>

	* gdb.dwarf2/dw2-error.exp: Add quiet to compile flags.
2020-04-24 13:21:49 +02:00
Tom de Vries
2016d3e60f [gdb/testsuite] Reduce errors after gdb exit in default_gdb_start
When running test-case gdb.base/readnever.exp with target board readnow, and
without commit 96038148d0 "[gdb/testsuite] Skip gdb.base/readnever.exp with
target board readnow", we run into a bunch of errors, starting with:
...
spawn gdb -nw -nx -data-directory data-directory -ex set sysroot -readnow \
  --readnever^M
gdb: '--readnow' and '--readnever' cannot be specified simultaneously^M
ERROR: : spawn id exp9 not open
    while executing
"expect {
-i exp9 -timeout 10
        -re "$gdb_prompt $" {
            verbose "Setting height to 0." 2
        }
...

The illegal combination of --readnow and --readnever causes gdb to start,
print an error message and exit.  There's a gdb_expect in default_gdb_start
that is supposed to detect the initial gdb prompt and handle related problems,
but since there's no eof case it succeeds, and default_gdb_start continues as
if the gdb prompt had been detected, causing the error above.

Fix this by adding an eof case to the gdb_expect, such that we have the more
accurate:
...
ERROR: (eof) GDB never initialized.
...

Further errors are triggered in clean_restart, because we're not testing for
gdb_start success.  Fix this by detecting gdb_start failure, and bailing out.

Finally, we're running into further errors in gdb.base/readnever.exp because
we're not testing for clean_restart success.  Fix this by making clean_restart
return -1 upon error, and testing for this.

Tested on x86_64-linux.

gdb/testsuite/ChangeLog:

2020-04-24  Tom de Vries  <tdevries@suse.de>

	* lib/gdb.exp (default_gdb_start): Handle eof.
	(clean_restart): Detect and handle gdb_start failure.  Return -1 upon
	failure.
	* gdb.base/readnever.exp: Handle clean_restart failure.
2020-04-24 12:21:49 +02:00
Tom de Vries
f80cb3b46a [gdb/contrib] Use temp dir for gdb-add-index in cc-with-tweaks.sh
When running test-case gdb.dwarf2/gdb-index.exp cleanly by issuing this
command:
...
$ rm -Rf build/gdb/testsuite/outputs/gdb.dwarf2/gdb-index
...
before running, it passes both with native and target board
cc-with-gdb-index.

But when we run the test-case first with native and then with
cc-with-gdb-index without intermediate cleanup, we get instead:
...
 Running src/gdb/testsuite/gdb.dwarf2/gdb-index.exp ...
 gdb compile failed, cc-with-tweaks.sh: Index file \
   build/gdb/testsuite/outputs/gdb.dwarf2/gdb-index/gdb-index.gdb-index \
   exists, won't clobber.

                 === gdb Summary ===

 # of untested testcases         1
...

What happens is that the native run produces a file
build/gdb/testsuite/outputs/gdb.dwarf2/gdb-index/gdb-index.gdb-index, which
causes gdb/contrib/cc-with-tweaks.sh to hit this code:
...
index_file="${output_file}.gdb-index"
if [ "$want_index" = true ] && [ -f "$index_file" ]
then
    echo "$myname: Index file $index_file exists, won't clobber." >&2
    exit 1
fi
...

The gdb-add-index script has a problem that it uses temp files alongside the
executable, filed as PR25843.

The code in cc-with-tweaks.sh attempts to detect the case that creating such a
temp file would overwrite an pre-existing file.  It however does this only for
a single file, while gdb-add-index uses more temporary files:
- <exec>.gdb-index
- <exec>.debug_names
- <exec>.debug_str
- <exec>.debug_str.merge
- <exec>.debug_str.err

Fix this by working around PR25843 in a more generic way:
- move the executable into a temp directory
- execute gdb-add-index, allowing it to create any temp file alongside the
  executable in the temp directory
- move the executable back to the original location

Tested on x86_64-linux, with target board cc-with-debug-index.

gdb/ChangeLog:

2020-04-24  Tom de Vries  <tdevries@suse.de>

	* contrib/cc-with-tweaks.sh: Remove <exec>.gdb-index file handling.
	Run gdb-add-index inside temp dir.
2020-04-24 11:31:06 +02:00
Alan Modra
2482f30615 readelf: memory leaks in process_dynamic_section
This fixes some code that assumed only one PT_LOAD would contain
DT_SYMTAB.  Which is normally the case, but fuzzers thoroughly mess
with object files.

	* readelf.c (get_num_dynamic_syms): Check for nbuckets and nchains
	non-zero.
	(process_dynamic_section): Call get_num_dynamic_syms once rather
	than in segment loop.  Break out of segment loop on a successful
	load of dynamic symbols.  Formatting.
	(process_object): Return error status from process_dynamic_section.
2020-04-24 10:52:26 +09:30
GDB Administrator
5e5bbc7e79 Automatic date update in version.in 2020-04-24 00:00:20 +00:00
Tom Tromey
29514b8728 Fix infinite loop in is_linked_with_cygwin_dll
There were some Windows timeouts after the last merge.  Debugging
showed that these were caused by an infinite loop in
is_linked_with_cygwin_dll when reading C:\Windows\SysWOW64\win32u.dll.

This patch fixes the problem by ensuring that the loop always makes
progress.

gdb/ChangeLog
2020-04-23  Tom Tromey  <tromey@adacore.com>

	* windows-tdep.c (is_linked_with_cygwin_dll): Always update "iter"
	in loop.
2020-04-23 12:53:15 -06:00
Luis Machado
5939967b35 Fix inline frame unwinding breakage
There has been some breakage for aarch64-linux, arm-linux and s390-linux in
terms of inline frame unwinding. There may be other targets, but these are
the ones i'm aware of.

The following testcases started to show numerous failures and trigger internal
errors in GDB after commit 1009d92fc6,
"Find tailcall frames before inline frames".

gdb.opt/inline-break.exp
gdb.opt/inline-cmds.exp
gdb.python/py-frame-inline.exp
gdb.reverse/insn-reverse.exp

The internal errors were of this kind:

binutils-gdb/gdb/frame.c:579: internal-error: frame_id get_frame_id(frame_info*): Assertion `fi->level == 0' failed.

After a lengthy investigation to try and find the cause of these assertions,
it seems we're dealing with some fragile/poorly documented code to handle inline
frames and we are attempting to unwind from this fragile section of code.

Before commit 1009d92fc6, the tailcall sniffer
was invoked from dwarf2_frame_prev_register. By the time we invoke the
dwarf2_frame_prev_register function, we've probably already calculated the
frame id (via compute_frame_id).

After said commit, the call to dwarf2_tailcall_sniffer_first was moved to
dwarf2_frame_cache. This is very early in a frame creation process, and
we're still calculating the frame ID (so compute_frame_id is in the call
stack).

This would be fine for regular frames, but the above testcases all deal
with some inline frames.

The particularity of inline frames is that their frame ID's depend on
the previous frame's ID, and the previous frame's ID relies in the inline
frame's registers. So it is a bit of a messy situation.

We have comments in various parts of the code warning about some of these
particularities.

In the case of dwarf2_tailcall_sniffer_first, we attempt to unwind the PC,
which goes through various functions until we eventually invoke
frame_unwind_got_register. This function will eventually attempt to create
a lazy value for a particular register, and this lazy value will require
a valid frame ID.  Since the inline frame doesn't have a valid frame ID
yet (remember we're still calculating the previous frame's ID so we can tell
what the inline frame ID is) we will call compute_frame_id for the inline
frame (level 0).

We'll eventually hit the assertion above, inside get_frame_id:

--
      /* If we haven't computed the frame id yet, then it must be that
         this is the current frame.  Compute it now, and stash the
         result.  The IDs of other frames are computed as soon as
         they're created, in order to detect cycles.  See
         get_prev_frame_if_no_cycle.  */
      gdb_assert (fi->level == 0);
--

It seems to me we shouldn't have reached this assertion without having the
inline frame ID already calculated. In fact, it seems we even start recursing
a bit when we invoke get_prev_frame_always within inline_frame_this_id. But
a check makes us quit the recursion and proceed to compute the id.

Here's the call stack for context:

 #0  get_prev_frame_always_1 (this_frame=0xaaaaab85a670) at ../../../repos/binutils-gdb/gdb/frame.c:2109
 RECURSION - #1  0x0000aaaaaae1d098 in get_prev_frame_always (this_frame=0xaaaaab85a670) at ../../../repos/binutils-gdb/gdb/frame.c:2124
 #2  0x0000aaaaaae95768 in inline_frame_this_id (this_frame=0xaaaaab85a670, this_cache=0xaaaaab85a688, this_id=0xaaaaab85a6d0)
     at ../../../repos/binutils-gdb/gdb/inline-frame.c:165
 #3  0x0000aaaaaae1916c in compute_frame_id (fi=0xaaaaab85a670) at ../../../repos/binutils-gdb/gdb/frame.c:550
 #4  0x0000aaaaaae19318 in get_frame_id (fi=0xaaaaab85a670) at ../../../repos/binutils-gdb/gdb/frame.c:582
 #5  0x0000aaaaaae13480 in value_of_register_lazy (frame=0xaaaaab85a730, regnum=30) at ../../../repos/binutils-gdb/gdb/findvar.c:296
 #6  0x0000aaaaaae16c00 in frame_unwind_got_register (frame=0xaaaaab85a730, regnum=30, new_regnum=30) at ../../../repos/binutils-gdb/gdb/frame-unwind.c:268
 #7  0x0000aaaaaad52604 in dwarf2_frame_prev_register (this_frame=0xaaaaab85a730, this_cache=0xaaaaab85a748, regnum=30)
     at ../../../repos/binutils-gdb/gdb/dwarf2/frame.c:1296
 #8  0x0000aaaaaae1ae68 in frame_unwind_register_value (next_frame=0xaaaaab85a730, regnum=30) at ../../../repos/binutils-gdb/gdb/frame.c:1229
 #9  0x0000aaaaaae1b304 in frame_unwind_register_unsigned (next_frame=0xaaaaab85a730, regnum=30) at ../../../repos/binutils-gdb/gdb/frame.c:1320
 #10 0x0000aaaaaab76574 in aarch64_dwarf2_prev_register (this_frame=0xaaaaab85a730, this_cache=0xaaaaab85a748, regnum=32)
     at ../../../repos/binutils-gdb/gdb/aarch64-tdep.c:1114
 #11 0x0000aaaaaad52724 in dwarf2_frame_prev_register (this_frame=0xaaaaab85a730, this_cache=0xaaaaab85a748, regnum=32)
     at ../../../repos/binutils-gdb/gdb/dwarf2/frame.c:1316
 #12 0x0000aaaaaae1ae68 in frame_unwind_register_value (next_frame=0xaaaaab85a730, regnum=32) at ../../../repos/binutils-gdb/gdb/frame.c:1229
 #13 0x0000aaaaaae1b304 in frame_unwind_register_unsigned (next_frame=0xaaaaab85a730, regnum=32) at ../../../repos/binutils-gdb/gdb/frame.c:1320
 #14 0x0000aaaaaae16a84 in default_unwind_pc (gdbarch=0xaaaaab81edc0, next_frame=0xaaaaab85a730) at ../../../repos/binutils-gdb/gdb/frame-unwind.c:223
 #15 0x0000aaaaaae32124 in gdbarch_unwind_pc (gdbarch=0xaaaaab81edc0, next_frame=0xaaaaab85a730) at ../../../repos/binutils-gdb/gdb/gdbarch.c:3074
 #16 0x0000aaaaaad4f15c in dwarf2_tailcall_sniffer_first (this_frame=0xaaaaab85a730, tailcall_cachep=0xaaaaab85a830, entry_cfa_sp_offsetp=0x0)
     at ../../../repos/binutils-gdb/gdb/dwarf2/frame-tailcall.c:388
 #17 0x0000aaaaaad520c0 in dwarf2_frame_cache (this_frame=0xaaaaab85a730, this_cache=0xaaaaab85a748) at ../../../repos/binutils-gdb/gdb/dwarf2/frame.c:1190
 #18 0x0000aaaaaad52204 in dwarf2_frame_this_id (this_frame=0xaaaaab85a730, this_cache=0xaaaaab85a748, this_id=0xaaaaab85a790)
     at ../../../repos/binutils-gdb/gdb/dwarf2/frame.c:1218
 #19 0x0000aaaaaae1916c in compute_frame_id (fi=0xaaaaab85a730) at ../../../repos/binutils-gdb/gdb/frame.c:550
 #20 0x0000aaaaaae1c958 in get_prev_frame_if_no_cycle (this_frame=0xaaaaab85a670) at ../../../repos/binutils-gdb/gdb/frame.c:1927
 #21 0x0000aaaaaae1cc44 in get_prev_frame_always_1 (this_frame=0xaaaaab85a670) at ../../../repos/binutils-gdb/gdb/frame.c:2006
 FIRST CALL - #22 0x0000aaaaaae1d098 in get_prev_frame_always (this_frame=0xaaaaab85a670) at ../../../repos/binutils-gdb/gdb/frame.c:2124
 #23 0x0000aaaaaae18f68 in skip_artificial_frames (frame=0xaaaaab85a670) at ../../../repos/binutils-gdb/gdb/frame.c:495
 #24 0x0000aaaaaae193e8 in get_stack_frame_id (next_frame=0xaaaaab85a670) at ../../../repos/binutils-gdb/gdb/frame.c:596
 #25 0x0000aaaaaae87a54 in process_event_stop_test (ecs=0xffffffffefc8) at ../../../repos/binutils-gdb/gdb/infrun.c:6857
 #26 0x0000aaaaaae86bdc in handle_signal_stop (ecs=0xffffffffefc8) at ../../../repos/binutils-gdb/gdb/infrun.c:6381
 #27 0x0000aaaaaae84fd0 in handle_inferior_event (ecs=0xffffffffefc8) at ../../../repos/binutils-gdb/gdb/infrun.c:5578
 #28 0x0000aaaaaae81588 in fetch_inferior_event (client_data=0x0) at ../../../repos/binutils-gdb/gdb/infrun.c:4020
 #29 0x0000aaaaaae5f7fc in inferior_event_handler (event_type=INF_REG_EVENT, client_data=0x0) at ../../../repos/binutils-gdb/gdb/inf-loop.c:43
 #30 0x0000aaaaaae8d768 in infrun_async_inferior_event_handler (data=0x0) at ../../../repos/binutils-gdb/gdb/infrun.c:9377
 #31 0x0000aaaaaabff970 in check_async_event_handlers () at ../../../repos/binutils-gdb/gdb/async-event.c:291
 #32 0x0000aaaaab27cbec in gdb_do_one_event () at ../../../repos/binutils-gdb/gdbsupport/event-loop.cc:194
 #33 0x0000aaaaaaef1894 in start_event_loop () at ../../../repos/binutils-gdb/gdb/main.c:356
 #34 0x0000aaaaaaef1a04 in captured_command_loop () at ../../../repos/binutils-gdb/gdb/main.c:416
 #35 0x0000aaaaaaef3338 in captured_main (data=0xfffffffff1f0) at ../../../repos/binutils-gdb/gdb/main.c:1254
 #36 0x0000aaaaaaef33a0 in gdb_main (args=0xfffffffff1f0) at ../../../repos/binutils-gdb/gdb/main.c:1269
 #37 0x0000aaaaaab6e0dc in main (argc=6, argv=0xfffffffff348) at ../../../repos/binutils-gdb/gdb/gdb.c:32

The following patch addresses this by using a function that unwinds the PC
from the next (inline) frame directly as opposed to creating a lazy value
that is bound to the next frame's ID (still not computed).

gdb/ChangeLog:

2020-04-23  Luis Machado  <luis.machado@linaro.org>

	* dwarf2/frame-tailcall.c (dwarf2_tailcall_sniffer_first): Use
	get_frame_register instead of gdbarch_unwind_pc.
2020-04-23 14:50:22 -03:00
Tom de Vries
70bc38f513 [gdb/symtab] Prefer def over decl (inter-CU case, with context)
This is a follow-up patch on "[PATCH][gdb/symtab] Prefer def over decl
(inter-CU case)" (
https://sourceware.org/pipermail/gdb-patches/2020-April/167489.html ).

Consider the test-case from that patch.  It contains a decl and def of var a
in different CUs, and tests whether var a can be printed using the def, even
if the decl is found first.

However, the test-case does this in a contextless environment, so if we add to
the test-case like this to set the context to the CU containing main:
...
 gdb_test "p a" { = \{1, 2\}}
+
+if ![runto_main] then {
+    fail "can't run to main"
+    return 0
+}
+
+gdb_test "p a" { = \{1, 2\}}
...
then the second test fails, because the decl is found in the context.

Fix this by preferring defs over decls in lookup_global_symbol.

Build and reg-tested on x86_64-linux.

gdb/ChangeLog:

2020-04-23  Tom de Vries  <tdevries@suse.de>

	* symtab.c (lookup_global_symbol): Prefer def over decl.

gdb/testsuite/ChangeLog:

2020-04-23  Tom de Vries  <tdevries@suse.de>

	* gdb.base/decl-before-def.exp: Run to main and print a again.
2020-04-23 15:42:47 +02:00
Tom de Vries
de82891ce5 [gdb/symtab] Prefer def over decl (inter-CU case)
When running test-case gdb.threads/tls.exp with target board -readnow, we
have:
...
(gdb) print a_thread_local^M
Cannot find thread-local storage for process 0, executable file tls/tls:^M
Cannot find thread-local variables on this target^M
(gdb) FAIL: gdb.threads/tls.exp: print a_thread_local
...
while with native we have:
...
(gdb) print a_thread_local^M
Cannot read `a_thread_local' without registers^M
(gdb) PASS: gdb.threads/tls.exp: print a_thread_local
...

The difference in behaviour can be explained as follows.  Without -readnow, we
have two a_thread_locals, the def and the decl, each in a different CU:
...
$ gdb -batch outputs/gdb.threads/tls/tls \
    -ex "maint expand-symtabs" \
    -ex "print a_thread_local" \
    -ex "maint print symbols" \
    | grep "a_thread_local;"
Cannot read `a_thread_local' without registers
 int a_thread_local; computed at runtime
 int a_thread_local; unresolved
...
and with -readnow, we have the opposite order:
...
$ gdb -readnow -batch outputs/gdb.threads/tls/tls  \
    -ex "maint expand-symtabs" \
    -ex "print a_thread_local" \
    -ex "maint print symbols" \
    | grep "a_thread_local;"
Cannot find thread-local storage for process 0, executable file tls/tls:
Cannot find thread-local variables on this target
 int a_thread_local; unresolved
 int a_thread_local; computed at runtime
...

Fix the FAIL by preferring the def over the decl (something we already do
intra-CU since the fix for PR24971, commit 93e55f0a03 "[gdb/symtab] Prefer var
def over decl").

Build and reg-tested on x86_64-linux.

gdb/ChangeLog:

2020-04-23  Tom de Vries  <tdevries@suse.de>

	PR symtab/25807
	* block.c (best_symbol, better_symbol): Promote to external.
	* block.h (best_symbol, better_symbol): Declare.
	* symtab.c (lookup_symbol_in_objfile_symtabs): Prefer def over
	decl.

gdb/testsuite/ChangeLog:

2020-04-23  Tom de Vries  <tdevries@suse.de>

	* gdb.base/decl-before-def-decl.c: New test.
	* gdb.base/decl-before-def-def.c: New test.
	* gdb.base/decl-before-def.exp: New file.
2020-04-23 15:42:47 +02:00
Tom Tromey
ecc6c6066b Fix Ada crash with .debug_names
PR ada/25837 points out a crash in the gdb testsuite when .debug_names
is used.  You can reproduce like:

    runtest --target_board=cc-with-debug-names \
        gdb.ada/big_packed_array.exp

The bug was introduced by commit e0802d599 ("Avoid copying in
lookup_name_info").  The problem is that the return type of
language_lookup_name changed, but in a way that didn't cause existing
callers to trigger a compilation error.  Previously, it returned a
"const string &", but after it returned a "const char *".  This caused
a string to be created in dw2_expand_symtabs_matching_symbol, but one
that had too short of a lifetime; so eventually the matcher cache
would wind up with invalid data.

This patch fixes the problem by updating the callers to use the new
type.

Tested on x86-64 Fedora 30.

gdb/ChangeLog
2020-04-23  Tom Tromey  <tromey@adacore.com>

	PR ada/25837:
	* dwarf2/read.c (dw2_expand_symtabs_matching_symbol): Store a
	"const char *", not a "const std::string &".
	<name_and_matcher::operator==>: Update.
	* unittests/lookup_name_info-selftests.c: Change type of
	"result".
2020-04-23 07:19:43 -06:00
Tom Tromey
740480b88a Remove iterate_over_inferiors
The last caller of iterate_over_inferiors is darwin-nat.c.  This patch
removes the calls from this file, and then remove
iterate_over_inferiors.

In general I think "external iteration" is to be preferred in gdb, the
main benefit being that the code is easier to read.

I rebuilt this on Darwin.  I seem to only have access to Darwin
systems where gdb does not yet work :-(, so I can't run the test
suite.

gdb/ChangeLog
2020-04-23  Tom Tromey  <tom@tromey.com>

	* inferior.h (iterate_over_inferiors): Don't declare.
	* inferior.c (iterate_over_inferiors): Remove.
	* darwin-nat.c (find_inferior_task_it, find_inferior_pid_it):
	Remove.
	(darwin_find_inferior_by_task, darwin_find_inferior_by_pid): Don't
	use iterate_over_inferiors.
	(darwin_resume_inferior_it)
	(struct resume_inferior_threads_param)
	(darwin_resume_inferior_threads_it): Remove.
	(darwin_nat_target::resume): Don't use iterate_over_inferiors.

Change-Id: Ib2fdf2c98e40f13156ff869ed3173d5f1fdae7ea
2020-04-23 06:26:31 -06:00
Anton Kolesov
2745674244 arc: Add support for ARC HS extra registers in core files
When a coredump is generated, there are a few registers in
ARC HS that are put under a special section, namely ".reg-v2".
It is for backward compatibility reasons with older tools that
we have decided not to extend the generic ".reg" section.

This patch makes it possible to display the information better
regarding that section.  Compare the output of "readelf" without
and with these changes:

$ readelf -n core     # without the patch
  ...
  LINUX    0x0000000c  Unknown note type: (0x00000600)
   description data: 78 08 00 00 2f 6c 64 2d 75 43 6c 69

$ readelf -n core     # with the patch
  ...
  LINUX    0x0000000c  NT_ARC_V2 (ARC HS accumulator/extra registers)
   description data: 78 08 00 00 2f 6c 64 2d 75 43 6c 69

In another commit (soon to be submitted), GDB will makes use of these
changes to parse the extra section and its registers.

bfd/ChangeLog
2020-03-26  Anton Kolesov  <anton.kolesov@synopsys.com>

	* elf-bfd.h (elfcore_write_arc_v2): Add prototype.
	* elf.c (elfcore_grok_arc_v2): New function.
	(elfcore_grok_note): Call the new function to handle the corresponding
	note.
	(elfcore_write_arc_v2): New function.
	(elfcore_write_register_note): Call the new function to handle the
	corresponding pseudo-sections.

binutils/ChangeLog
2020-03-26  Anton Kolesov  <anton.kolesov@synopsys.com>

	* readelf.c (get_note_type): Handle NT_ARC_V2.

include/elf/ChangeLog
2020-03-26  Anton Kolesov  <anton.kolesov@synopsys.com>

	* common.h (NT_ARC_V2): New macro definitions.
2020-04-23 11:09:09 +03:00