Commit Graph

91492 Commits

Author SHA1 Message Date
Tom Tromey
5eb5f85062 Don't use -fdiagnostics-color=never for rustc
I noticed that the gdb.rust tests fail because the test suite passes
-fdiagnostics-color=never to rustc.  This is not a recognized rustc
option, and the test suite already handles passing the appropriate
option to the Rust compiler.

This patch fixes the problem.

testsuite/ChangeLog
2017-09-05  Tom Tromey  <tom@tromey.com>

	* lib/gdb.exp (gdb_compile): Don't use universal_compile_options
	for rust.
2017-09-05 12:08:03 -06:00
Simon Marchi
ae780a21f2 Test different follow-exec-mode settings in gdb.multi/multi-arch-exec.exp
Using follow-exec-mode "new" takes a different code path than "same", so
it's interesting to test this path in combination with a change in
architecture of the inferior.  This test fails if you remove the
previous patch.

gdb/testsuite/ChangeLog:

	* gdb.multi/multi-arch-exec.exp: Test with different
	"follow-exec-mode" settings.
	(do_test): New procedure.
2017-09-05 17:42:04 +02:00
Simon Marchi
bf93d7ba99 Add thread after updating gdbarch when exec'ing
As mentioned in the previous patch, we should avoid doing register reads
after a process does an exec and before we've updated that inferior's
gdbarch.  Otherwise, we may interpret the registers using the wrong
architecture.  When a process does an exec with "follow-exec-mode new",
a new inferior is added by follow_exec.  The gdbarch of that new
inferior is at first set to some default value, probably specific to the
gdb build (I get "i386" here), which may not be the right one.  It is
updated later by the call to target_find_description.  Before that
point, if we try to read the inferior's registers, we may not interpret
them correctly.  This has been exposed by a failure in
gdb.base/foll-exec-mode.exp after the previous patch, with:

  Remote 'g' packet reply is too long (expected 312 bytes, got 816 bytes)

The call to "add_thread" done just after adding the inferior is
problematic, because it ends up reading the registers (because the ptid
is re-used, we end up doing a switch_to_thread to it, which tries to
update stop_pc).  The registers returned by gdbserver are the x86-64
ones, while we try to interpret them using the "i386" gdbarch.

Postponing the call to add_thread to until the target
description/gdbarch has been updated seems to fix the issue.

As to why this issue was uncovered by the previous patch: what I think
happened before that patch is that since we were updating stop_pc before
switching to the new inferior, we were filling the regcache associated
to the ptid (this worked fine as long as the architectures of the
previous and new process images were the same).  The call to
switch_to_thread then worked, because the register read hit the
regcache.  Now, it triggers a register read, while the gdbarch is not
set correctly, leading to the "reply is too long" error.  If this is
right, it sounds wrong that we delete and re-add a thread with the same
ptid, and are able to access the registers from the deleted thread.
When we delete a thread, should we clear the regcache associated to that
ptid, so that the new thread starts with a fresh/empty regcache?

gdb/ChangeLog:

	* infrun.c (follow_exec): Call add_thread after
	target_find_description.
2017-09-05 17:41:03 +02:00
Simon Marchi
1bb7c05977 Read stop_pc after updating the gdbarch when exec'ing
When an inferior execs and changes architecture (e.g. 64 bits to 32
bits), the gdbarch associated to the inferior is updated by the
follow_exec call in handle_inferior_event_1.  We should avoid doing any
register read before that point, because the registers sent by the
remote side will be those of the new architecture, but we would
interpret them using the old architecture.  We do just that by setting
stop_pc during this window, which obviously requires reading the
registers.  This results in gdb.multi/multi-arch-exec.exp failing, GDB
outputting the following error:

  Truncated register 50 in remote 'g' packet

This patch fixes that by postponing the setting of stop_pc to after
we've updated the inferior gdbarch.

This bug was hiding another problem, and as such introduces some
failures in gdb.base/foll-exec-mode.exp.  The following patch takes care
of that.

gdb/ChangeLog:

	* infrun.c (handle_inferior_event_1): When exec'ing, read
	stop_pc after follow_exec.
2017-09-05 17:41:03 +02:00
Simon Marchi
fc80982757 Improve "'g' reply is is to long" error message
... by adding the expected size, and the received size.  I found this
useful when debugging gdbarch/remote issues, since it gives a hint of
what gdb expects and what the remote sent.

gdb/ChangeLog:

	* remote.c (process_g_packet): Update error message.
2017-09-05 17:41:03 +02:00
Yao Qi
d2fcdd8546 Add i386.o to gdb_target_obs for x86_64-* targets
This patch fixes the build failure caused by 22916b0
(Convert the rest x86 target descriptions).

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* configure.tgt (gdb_target_obs): Add i386.o for x86_64-*
	targets.
2017-09-05 14:46:47 +01:00
Pedro Alves
e69570ee18 eval.c:evaluate_subexp_standard: Factor out function call handling
While working on the no-debug-info debugging improvements, I found
evaluate_subexp_standard's function call code unnecessarily long and
hard to navigate and debug.  The use of goto doesn't help either.

This commit tries to improve things by factoring out the
function-call-related code to separate helper functions.

gdb/ChangeLog:
2017-09-05  Pedro Alves  <palves@redhat.com>

	* eval.c (eval_call, evaluate_funcall): New functions, factored
	out from ...
	(evaluate_subexp_standard): ... this.
2017-09-05 12:13:57 +01:00
Nick Clifton
f17e9d8ab5 Fix a buffer overrun when parsing a corrupt MIPS ELF binary.
PR 21995
	* readelf.c (process_mips_specific): Add checks for a NULL data
	pointer.
2017-09-05 12:09:14 +01:00
Yao Qi
22916b0786 Convert the rest x86 target descriptions
This patch changes the rest of x86 target descriptions in GDB and
GDBserver.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* amd64-tdep.c (amd64_target_description): Create target
	descriptions.
	(_initialize_amd64_tdep): Don't call functions
	initialize_tdesc_amd64_*.  Add self tests.
	* arch/amd64.c (amd64_create_target_description): Add parameter
	is_linux.  Call set_tdesc_osabi if is_linux is true.
	* arch/amd64.h (amd64_create_target_description): Update the
	declaration.
	* arch/i386.c (i386_create_target_description): Add parameter
	is_linux.  Call set_tdesc_osabi if is_linux is true.
	* arch/i386.h (i386_create_target_description): Update
	declaration.
	* configure.tgt: Add i386.o to gdb_target_obs.
	* features/Makefile (XMLTOC): Remove i386/*.xml.
	* features/i386/amd64-avx-avx512.c: Remove.
	* features/i386/amd64-avx-mpx-avx512-pku.c: Remove.
	* features/i386/amd64-avx-mpx.c: Remove.
	* features/i386/amd64-avx.c: Remove.
	* features/i386/amd64-mpx.c: Remove.
	* features/i386/amd64.c: Remove.
	* features/i386/i386-avx-avx512.c: Remove.
	* features/i386/i386-avx-mpx-avx512-pku.c: Remove.
	* features/i386/i386-avx-mpx.c: Remove.
	* features/i386/i386-avx.c: Remove.
	* features/i386/i386-mmx.c: Remove.
	* features/i386/i386-mpx.c: Remove.
	* features/i386/i386.c: Remove.
	* i386-tdep.c: Don't include features/i386/i386*.c., include
	target-descriptions.h and arch/i386.h.
	(i386_target_description): Create target descriptions.
	(i386_gdbarch_init): Don't call initialize_tdesc_i386_*
	functions.  Do self tests.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* configure.srv (srv_i386_regobj): Remove.
	(srv_amd64_regobj): Remove.
	(srv_regobj): Set it to "" for x86 non-linux targets.
	* linux-x86-tdesc.c (i386_linux_read_description):
	* lynx-i386-low.c: Include x86-xstate.h and arch/i386.h.
	(init_registers_i386): Remove the declaration.
	(tdesc_i386): Remove the declaration.
	(lynx_i386_arch_setup): Call i386_create_target_description.
	* nto-x86-low.c: Likewise.
	* win32-i386-low.c [__x86_64__]: include arch/amd64.h.
	[!__x86_64__]: include arch/i386.h.
	(i386_arch_setup) [__x86_64__]: Call amd64_create_target_description.
2017-09-05 09:54:54 +01:00
Yao Qi
0854b7b187 Remove features/i386/amd64-*linux.c and features/i386/x32-*linux.c
gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* features/Makefile (XMLTOC): Remove i386/amd64XXX-linux.xml.
	* features/i386/amd64-avx-avx512-linux.c: Removed.
	* features/i386/amd64-avx-linux.c: Removed.
	* features/i386/amd64-avx-mpx-avx512-pku-linux.c: Removed.
	* features/i386/amd64-avx-mpx-linux.c: Removed.
	* features/i386/amd64-linux.c: Removed.
	* features/i386/amd64-mpx-linux.c: Removed.
	* features/i386/x32-avx-avx512-linux.c: Removed.
	* features/i386/x32-avx-linux.c: Removed.
	* features/i386/x32-linux.c: Removed.
2017-09-05 09:54:54 +01:00
Yao Qi
38602d55e0 [GDBserver] Shorten srv_amd64_linux_xmlfiles
GDBserver now is able to generate target descriptions from features, so
don't need to remember these target description files.

Note that it should be i386/amd64-avx-avx512-linux.xml instead of
i386/amd64-avx-avx512.xml in $srv_amd64_linux_xmlfiles.  This patch
removes it anyway.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* configure.srv (srv_amd64_linux_xmlfiles): Remove
	i386/amd64-XXX-linux from it.
2017-09-05 09:54:54 +01:00
Yao Qi
44b886ff15 [GDBserver] Use pre-generated amd64-linux tdesc as test
Now, all these amd64-linux pre-generated tdesc can be used as test, so
don't need to build them if $development is false.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* configure.srv: Empty srv_amd64_linux_regobj if $development is
	false.
	(ipa_amd64_linux_regobj): Remove.
	(ipa_x32_linux_regobj): Remove.
2017-09-05 09:54:54 +01:00
Yao Qi
b4570e4b30 Convert amd64-linux target descriptions
This patch changes amd64-linux target descriptions so that they can be
dynamically generated in both GDB and GDBserver.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* Makefile.in (arch-amd64.o): New rule.
	* configure.srv: Append arch-amd64.o.
	* linux-amd64-ipa.c: Include common/x86-xstate.h.
	(get_ipa_tdesc): Call amd64_linux_read_description.
	(initialize_low_tracepoint): Don't call init_registers_x32_XXX
	and init_registers_amd64_XXX.
	* linux-x86-low.c (x86_linux_read_description): Call
	amd64_linux_read_description.
	(x86_get_ipa_tdesc_idx): Call amd64_get_ipa_tdesc_idx.
	(initialize_low_arch): Don't call init_registers_x32_XXX and
	init_registers_amd64_XXX.
	* linux-x86-tdesc-selftest.c: Declare init_registers_amd64_XXX
	and tdesc_amd64_XXX.
	[__x86_64__] (amd64_tdesc_test): New function.
	(initialize_low_tdesc) [__x86_64__]: Call init_registers_x32_XXX
	and init_registers_amd64_XXX.
	* linux-x86-tdesc.c: Include arch/amd64.h.
	(xcr0_to_tdesc_idx): New function.
	(i386_linux_read_description): New function.
	(amd64_get_ipa_tdesc_idx): New function.
	* linux-x86-tdesc.h (amd64_get_ipa_tdesc_idx): Declare.
	(amd64_get_ipa_tdesc): Declare.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* amd64-linux-tdep.c: Include arch/amd64.h.  Don't include
	features/i386/*.c.
	(amd64_linux_read_description): Call
	amd64_create_target_description.
	* arch/amd64.c: New file.
	* arch/amd64.h: New file.
	* configure.tgt (x86_64-*-linux*): Append amd64.o.
	* Makefile.in (ALL_64_TARGET_OBS): Append amd64.o.
2017-09-05 09:54:54 +01:00
Yao Qi
6c73f67f9c Lazily and dynamically create amd64-linux target descriptions
This patch starts to use the generate c feature files to dynamically
create amd64-linux target descriptions.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* amd64-linux-tdep.c: Don't include amd64-XXX-linux and
	x32-XXX-linux.c.  Include 64bit-XX.c and x32-XX.c.
	(amd64_linux_read_description): Create target descriptions.
	(_initialize_amd64_linux_tdep): Don't call initialize_tdesc_XXX
	functions.  Add unit tests.
	* features/Makefile (FEATURE_XMLFILES): Append 64bit-XXX.xml and
	x32-core.xml.
	* features/i386/64bit-avx.c: Generated.
	* features/i386/64bit-avx512.c: Generated.
	* features/i386/64bit-core.c: Generated.
	* features/i386/64bit-linux.c: Generated.
	* features/i386/64bit-mpx.c: Generated.
	* features/i386/64bit-pkeys.c: Generated.
	* features/i386/64bit-segments.c: Generated.
	* features/i386/64bit-sse.c: Generated.
	* features/i386/x32-core.c: Generated.
	* target-descriptions.c (maint_print_c_tdesc_cmd): Print feature
	c files for amd64-linux and x32-linux.
2017-09-05 09:54:54 +01:00
Yao Qi
9d3d478be5 Centralize amd64-linux target descriptions
This patch adds a new function amd64_linux_read_description, which
creates amd64-linux target descriptions according to its two
arguments, xcr0 and is_x32.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* amd64-linux-tdep.c (amd64_linux_read_description): New
	function.
	(amd64_linux_core_read_description): Call
	amd64_linux_read_description.
	(amd64_linux_init_abi): Likewise.
	(amd64_x32_linux_init_abi): Likewise.
	* amd64-linux-tdep.h (amd64_linux_read_description): Declare.
	* x86-linux-nat.c (x86_linux_read_description): Call
	amd64_linux_read_description.
2017-09-05 09:54:53 +01:00
Yao Qi
b9f1d50ffc Update comments in amd64_linux_core_read_description
gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* amd64-linux-tdep.c (amd64_linux_core_read_description): Update
	comments.
2017-09-05 09:54:53 +01:00
Yao Qi
d1f28ea24a [GDBserver] Shorten srv_i386_linux_xmlfiles
GDBserver now is able to generate target descriptions from features, so
don't need to remember these target description files.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* configure.srv (srv_i386_linux_xmlfiles): Remove
	i386/i386-XXX-linux.xml from it.
2017-09-05 09:54:53 +01:00
Yao Qi
25a93583f3 [GDBserver] Use pre-generated tdesc as test
Now, these *-generate.c files are only used in GDBserver for unit test.
If $development is false (in release), these *-generate.c files won't be
used at all.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* configure.srv: Set srv_i386_linux_regobj empty if $development
	is false.
	* linux-i386-ipa.c (initialize_low_tracepoint): Don't call
	initialize_low_tdesc.
	* linux-x86-low.c (initialize_low_arch): Wrap initialize_low_tdesc
	with #if initialize_low_tdesc.
	* linux-x86-tdesc-selftest.c: New file.
	* linux-x86-tdesc.c: Move code to linux-x86-tdesc-selftest.c.
2017-09-05 09:54:53 +01:00
Yao Qi
188c9e6dcb Remove features/i386/i386-*linux.c
Now, features/i386/i386-XXX-linux.c are not used, remove them.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* features/Makefile (XMLTOC): Remove i386/i386-XX-linux.xml.
	* features/i386/i386-avx-avx512-linux.c: Remove.
	* features/i386/i386-avx-linux.c: Remove.
	* features/i386/i386-avx-mpx-avx512-pku-linux.c: Remove.
	* features/i386/i386-avx-mpx-linux.c: Remove.
	* features/i386/i386-linux.c: Remove.
	* features/i386/i386-mmx-linux.c: Remove.
	* features/i386/i386-mpx-linux.c: Remove.
2017-09-05 09:54:53 +01:00
Yao Qi
5f035c0716 Share i386-linux target description between GDB and GDBserver
The code on creating i386-linux target descriptions are quite similar
between GDB and GDBserver, so this patch moves them into a shared file
arch/i386.c.  I didn't name it as i386-linux.c, because I want to reuse it
to create other i386 non-linux target descriptions later.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* Makefile.in (ALL_TARGET_OBS): Add i386.o.
	(SFILES): Add arch/i386.c.
	(HFILES_NO_SRCDIR): Add arch/i386.h.
	* arch/i386.c: New file.
	* arch/i386.h: New file.
	* arch/tdesc.h (allocate_target_description): Declare.
	(set_tdesc_architecture): Declare.
	(set_tdesc_osabi): Declare.
	* configure.tgt (i[34567]86-*-linux*): Add i386.o.
	* i386-linux-tdep.c: Don't include ../features/i386/32bit-XXX.c.
	include arch/i386.h.
	(i386_linux_read_description): Remove code and call
	i386_create_target_description.
	(set_tdesc_architecture): New function.
	(set_tdesc_osabi): New function.
	* target-descriptions.h (allocate_target_description): Remove.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* Makefile.in (arch-i386.o): New rule.
	* configure.srv (i[34567]86-*-linux*): Add arch-i386.o.
	(x86_64-*-linux*): Likewise.
	* linux-x86-tdesc.c: Don't include ../features/i386/32bit-XXX.c,
	include arch/i386.h.
	(i386_linux_read_description): Remove code and call
	i386_create_target_description.
	* tdesc.c (allocate_target_description): New function.
	* tdesc.h (set_tdesc_architecture): Remove declaration.
	(set_tdesc_osabi): Likewise.
2017-09-05 09:54:53 +01:00
Yao Qi
0abe8a8992 Dynamically composite xml in reply to GDB
GDBserver still uses pre-generated target descriptions in order to
reply to GDB's query on target description (see xml-builtin-generated.c
in GDBserver build directory).  This patch teaches GDBserver to
create XML contents according to the target descriptions rather than
using pre-generated ones.

First, change target feature c files to pass the feature xml file
name to tdesc_create_feature, so that target description in GDBserver
can record them, and create XML contents from these features in
buffer, like

  ...
  <xi:include href="$FEATURE1_XML_NAME"/>
  <xi:include href="$FEATURE2_XML_NAME"/>
  ...

and send this buffer back to GDB.

Note that this patch reuses target_desc.xmltarget a little bit, which is
to hold the XML contents dynamically generated in tdesc_get_features_xml.
However, it is not xfree'ed in ~target_desc, because we can't tell it is
from xstrdup or a literal string.  Since we don't delete target_desc,
there is no memory leak yet.  After we change all target descriptions to
the new style, target_desc.xmltarget is from xstrdup, then, we can safely
xfree it in ~target_desc.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* arch/tdesc.h (tdesc_create_feature): Add an argument xml.
	* target-descriptions.c (tdesc_create_feature): Likewise, and
	adjust code.
	* features/i386/32bit-avx.c: Re-generated.
	* features/i386/32bit-avx512.c: Re-generated.
	* features/i386/32bit-core.c: Re-generated.
	* features/i386/32bit-linux.c: Re-generated.
	* features/i386/32bit-mpx.c: Re-generated.
	* features/i386/32bit-pkeys.c: Re-generated.
	* features/i386/32bit-sse.c: Re-generated.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* linux-x86-tdesc.c: Don't include <inttypes.h>.
	(i386_linux_read_description) [!IN_PROCESS_AGENT]: Call
	set_tdesc_architecture and set_tdesc_osabi.  Remove code setting
	.xmltarget.
	* server.c (get_features_xml): Call tdesc_get_features_xml.
	* tdesc.c (set_tdesc_architecture): New function.
	(set_tdesc_osabi): New function.
	(tdesc_get_features_xml): New function.
	(tdesc_create_feature): Add an argument.
	* tdesc.h (struct target_desc) <features>: New field.
	<arch, osabi>: New field.
	(~target_desc): xfree features, arch, and osabi.
	(target_desc::oerator==): Don't compare .xmltarget.
	[!IN_PROCESS_AGENT] (set_tdesc_architecture): Declare.
	(set_tdesc_osabi): Likewise.
	(tdesc_get_features_xml): Likewise.
2017-09-05 09:54:53 +01:00
Yao Qi
0a188386c0 [GDBserver] unit test to i386_tdesc
This patch adds a unit test in GDBserver to test dynamically created
target descriptions equal these pre-generated ones.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* linux-x86-tdesc.c: Include selftest.h.
	(i386_tdesc_test): New function.
	(initialize_low_tdesc): Call selftests::register_test.
	* tdesc.h: Include regdef.h.
	(target_desc): Override operator == and !=.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* regformats/regdef.h (struct reg): Override operator == and !=.
2017-09-05 09:54:53 +01:00
Yao Qi
f49ff00066 [GDBserver] Centralize tdesc for i386-linux
tdesc_i386_XXX_linux is used in many places in linux-x86-low.c and this
patch adds a new function i386_linux_read_description to return the right
tdesc according to xcr0.  i386_linux_read_description is quite similar to
the counterpart in GDB, and the following patch will share the duplicated
code, so this patch adds arch/tdesc.h includes the declarations of various
tdesc apis which are used by the shared code.  The generated c feature
files can include arch/tdesc.h only.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* configure.srv (srv_tgtobj): Append linux-x86-tdesc.o.
	(ipa_obj): Likewise.
	* linux-i386-ipa.c: Include common/x86-xstate.h
	(get_ipa_tdesc): Call i386_linux_read_description.
	(initialize_low_tracepoint): Don't call  init_registers_XXX
	functions, call initialize_low_tdesc instead.
	* linux-x86-low.c (x86_linux_read_description): Call
	i386_linux_read_description.
	(initialize_low_arch): Don't call init_registers_i386_XXX
	functions, call initialize_low_tdesc.
	* linux-x86-tdesc.c: New file.
	* linux-x86-tdesc.h (x86_linux_tdesc): New X86_TDESC_LAST.
	(i386_get_ipa_tdesc_idx): Declare.
	(i386_get_ipa_tdesc): Declare.
	(initialize_low_tdesc): Declare.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* arch/tdesc.h: New file.
	* regformats/regdat.sh: Generate code using tdesc_create_reg.
	* target-descriptions.c: Update comments.
	* target-descriptions.h: Include "arch/tdesc.h".  Remove the
	declarations.
	* features/i386/32bit-avx.c: Re-generated.
	* features/i386/32bit-avx512.c: Re-generated.
	* features/i386/32bit-core.c: Re-generated.
	* features/i386/32bit-linux.c: Re-generated.
	* features/i386/32bit-mpx.c: Re-generated.
	* features/i386/32bit-pkeys.c: Re-generated.
	* features/i386/32bit-sse.c: Re-generated.
2017-09-05 09:54:53 +01:00
Yao Qi
2b68ef2f11 Return X86_TDESC_MMX in x86_get_ipa_tdesc_idx
gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* linux-x86-low.c (x86_get_ipa_tdesc_idx): Use X86_TDESC_MMX
	instead of 0.
2017-09-05 09:54:52 +01:00
Yao Qi
f7000548a2 Use VEC for target_desc.reg_defs
Nowadays, target_desc.reg_defs is a pointer points to a pre-generated
array, which is not flexible.  This patch changes it from an array
to a VEC so that GDBserver can create target descriptions dynamically
later.  Instead of using pre-generated array, the -generated.c calls
VEC_safe_push to add each register to vector.

Since target_desc.reg_defs is used in IPA, we need to build common/vec.c
for IPA too.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* Makefile.in (IPA_OBJS): Add vec-ipa.o
	* regcache.c (get_thread_regcache): Use VEC_length.
	(init_register_cache): Likewise.
	(regcache_cpy): Likewise.
	(registers_to_string): Iterate reg_defs via VEC_iterate.
	(find_regno): Likewise.
	(find_register_by_number): Use VEC_index.
	(register_size): Call find_register_by_number.
	(register_data): Call find_register_by_number.
	(supply_regblock): Use VEC_length.
	(regcache_raw_read_unsigned): Likewise.
	* tdesc.c (init_target_desc): Iterate reg_defs via
	VEC_iterate.
	(default_description): Update initializer.
	(copy_target_description): Don't update field num_registers.
	* tdesc.h (struct target_desc) <reg_defs>: Change it to VEC.
	<num_registers>: Remove.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* regformats/regdat.sh: Update generated code.
2017-09-05 09:54:52 +01:00
Yao Qi
c9a5e2a5b2 Adjust code generated by regformats/regdat.sh
regformats/regdat.sh generate some *-generated.c files when GDBserver
is built.  Each .c file has some static variables, which are only used
within function init_registers_XXX, like this,

static struct reg regs_i386_linux[] = {
  { "eax", 0, 32 },
  { "ecx", 32, 32 },
  ...
};

static const char *expedite_regs_i386_linux[] = { "ebp", "esp", "eip", 0 };
static const char *xmltarget_i386_linux = "i386-linux.xml";

void
init_registers_i386_linux (void)
{
  ...
}

This patch moves these static variables' definitions to function
init_registers_XXX, so the generated files look like this,

void
init_registers_i386_linux (void)
{
  static struct target_desc tdesc_i386_linux_s;
  struct target_desc *result = &tdesc_i386_linux_s;
static struct reg regs_i386_linux[] = {
  ...
};

static const char *expedite_regs_i386_linux[] = { "ebp", "esp", "eip", 0 };
static const char *xmltarget_i386_linux = "i386-linux.xml";

  ...
}

We want GDBserver create target descriptions dynamically in each
init_registers_XXXX functions, so this patch moves all the related code
into function init_registers_XXXX, so that the following patch can easily
change function init_registers_XXXX to create target description
dynamically, rather than using current pre-generated array.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* regformats/regdat.sh: Adjust code order.
2017-09-05 09:54:52 +01:00
Simon Marchi
d6b687ac7a expprint: Fix format string warning
My compiler (gcc 5.4.0, clang 3.8) gives this warning:

/home/emaisin/src/binutils-gdb/gdb/expprint.c: In lambda function:
/home/emaisin/src/binutils-gdb/gdb/expprint.c:1055:35: error: format not a string literal and no format arguments [-Werror=format-security]
      fprintf_filtered (stream, mod);
                                   ^

Fix it by not using the passed string as the format string.

gdb/ChangeLog:

	* expprint.c (dump_subexp_body_standard): Use constant format
	string in fprintf_filtered call.
2017-09-05 09:01:13 +02:00
John Baldwin
625ce09c1c Define an error function in the PPC simulator library.
Previously this used the error function from GDB directly when linked
against GDB instead of the error method in the host callbacks
structure.  This was exposed via a link error when GDB was converted
to C++.  The error function invokes the error callback similar to
sim_io_error.

Note that there are also error functions in sim/ppc/main.c and
sim/ppc/misc.c.  The ppc libsim.a expects each consumer to provide
several symbols used by the library including "error".  sim-calls.c
provides these symbols when the library is linked into gdb.  The dgen,
igen, tmp-filter, tmp-ld-decode, tmp-ld-cache, and tmp-ld-insn programs
use the functions from misc.c.  psim uses the functions from main.c.

sim/ppc/ChangeLog:

	PR sim/20863
	* sim_calls.c (error): New function.
2017-09-04 19:56:00 -07:00
John Baldwin
a379bfd00e Enable support for x86 debug registers on NetBSD.
NetBSD recently added PT_GETDBREGS and PT_SETDBREGS ptrace operations
that match the existing ones supported by x86-bsd-nat.c.  NetBSD's
headers do not provide the DBREG_DRX helper macro, so define a local
version in x86-bsd-nat.c.  In addition, add the x86-nat.o and x86-dregs.o
object files to the native NetBSD x86 build targets.

gdb/ChangeLog:

	* configure.nat: Add "x86-nat.o x86-dregs.o" for NetBSD/amd64 and
	NetBSD/i386.
	* x86-bsd-nat.c [!DBREG_DRX && __NetBSD__]: Define DBREG_DRX.
2017-09-04 19:34:48 -07:00
John Baldwin
f7efc967ba Make <sys/user.h> include in bsd-kvm.c conditional on HAVE_SYS_USER_H.
NetBSD has recently removed <sys/user.h>.

gdb/ChangeLog:

	* bsd-kvm.c: Make <sys/user.h> conditional on HAVE_SYS_USER_H.
2017-09-04 19:34:48 -07:00
John Baldwin
c49fbc6c79 Define _KMEMUSER before including BSD kernel headers.
Recent versions of NetBSD hide certain kernel structures needed by the
KVM target from userland unless this macro is defined.

gdb/ChangeLog:

	* bsd-kvm.o: Define _KMEMUSER.
	* configure.ac: Define _KMEMUSER when checking for "struct lwp".
	* configure: Regenerate.
2017-09-04 19:34:48 -07:00
John Baldwin
26562e73d8 Include "x86-xstate.h" for X86_XSTATE_* constants.
gdb/ChangeLog:

	* amd64-fbsd-nat.c: Add include of "x86-xstate.h".
	* i386-fbsd-nat.c: Likewise.
2017-09-04 19:31:33 -07:00
GDB Administrator
0097251b8a Automatic date update in version.in 2017-09-05 00:00:18 +00:00
Alexander Fedotov-B55613
83eef88358 Missing relocation R_PPC_VLE_ADDR20 and add VLE flag to details in readelf
include/
	* elf/ppc.h (R_PPC_VLE_ADDR20): New relocation.
bfd/
	* elf32-ppc.c (ppc_elf_howto_raw): Add R_PPC_VLE_ADDR20.
	(ppc_elf_check_relocs): Handle it.
	(ppc_elf_vle_split20): New function.
	(ppc_elf_relocate_section): Handle R_PPC_VLE_ADDR20.
binutils/
	* readelf.c (get_elf_section_flags): Add VLE.
	(process_section_headers): Add VLE key to details.
gas/
	* config/tc-ppc.c (md_parse_option): Handle "mno-vle" flag.
	(ppc_elf_section_letter): New function.
	* config/tc-ppc.h (md_elf_section_letter): New.
	* testsuite/gas/elf/section10.d: Adjust for VLE.
2017-09-05 08:42:27 +09:30
John Baldwin
31cf148787 Explicitly include <array> for std::array<>.
gdb/ChangeLog:

	* unittests/array-view-selftests.c: Add include of <array>.
2017-09-04 15:58:38 -07:00
John Baldwin
5b9f8a7c6e Catch up to recent changes to call_function_by_hand().
gdb/ChangeLog:

	* spu-tdep.c (flush_ea_cache): Add missing argument to
	call_function_by_hand.
2017-09-04 15:57:02 -07:00
Pedro Alves
d69cf9b207 Document "no debug info debugging" improvements
Here's the documentation bits for all the improvements done in
previous commits.

Note that the original "weak alias functions" paragraph ends up
disappearing, because this patch, which I'm considering kind of part
of this series, makes the alias case Just Work:
  https://sourceware.org/ml/gdb-patches/2017-07/msg00018.html

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* NEWS (Safer support for debugging with no debug info): New.

gdb/doc/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* gdb.texinfo (Variables) <Program Variables>: Document inspecting
	no-debug-info variables.
	(Symbols) <Examining the Symbol Table>: Document inspecting
	no-debug-info types.
	(Calling) <Calling functions with no debug info>: New subsection,
	documenting calling no-debug-info functions.
	(Non-debug DLL Symbols) <Working with Minimal Symbols>: Update.
2017-09-04 20:21:16 +01:00
Pedro Alves
3693fdb3c8 Make "p S::method() const::static_var" work too
Trying to print a function local static variable of a const-qualified
method still doesn't work after the previous fixes:

  (gdb) p 'S::method() const'::static_var
  $1 = {i1 = 1, i2 = 2, i3 = 3}
  (gdb) p S::method() const::static_var
  No symbol "static_var" in specified context.

The reason is that the expression parser/evaluator loses the "const",
and the above unquoted case is just like trying to print a variable of
the non-const overload, if it exists, even.  As if the above unquoted
case had been written as:

  (gdb) p S::method()::static_var
  No symbol "static_var" in specified context.

We can see the problem without static vars in the picture.  With:

 struct S
 {
    void method ();
    void method () const;
 };

Compare:

  (gdb) print 'S::method(void) const'
  $1 = {void (const S * const)} 0x400606 <S::method() const>
  (gdb) print S::method(void) const
  $2 = {void (S * const)} 0x4005d8 <S::method()>   # wrong method!

That's what we need to fix.  If we fix that, the function local static
case starts working.

The grammar production for function/method types is this one:

  exp:       exp '(' parameter_typelist ')' const_or_volatile

This results in a TYPE_INSTANCE expression evaluator operator.  For
the example above, we get something like this ("set debug expression 1"):

...
            0  TYPE_INSTANCE         1 TypeInstance: Type @0x560fda958be0 (void)
            5    OP_SCOPE              Type @0x560fdaa544d8 (S) Field name: `method'
...

While evaluating TYPE_INSTANCE, we end up in
value_struct_elt_for_reference, trying to find the method named
"method" that has the prototype recorded in TYPE_INSTANCE.  In this
case, TYPE_INSTANCE says that we're looking for a method that has
"(void)" as parameters (that's what "1 TypeInstance: Type
@0x560fda958be0 (void)" above means.  The trouble is that nowhere in
this mechanism do we communicate to value_struct_elt_for_reference
that we're looking for the _const_ overload.
value_struct_elt_for_reference only compared parameters, and the
non-const "method()" overload has matching parameters, so it's
considered the right match...

Conveniently, the "const_or_volatile" production in the grammar
already records "const" and "volatile" info in the type stack.  The
type stack is not used in this code path, but we can borrow the
information.  The patch converts the info in the type stack to an
"instance flags" enum, and adds that as another element in
TYPE_INSTANCE operators.  This type instance flags is then applied to
the temporary type that is passed to value_struct_elt_for_reference
for matching.

The other side of the problem is that methods in the debug info aren't
marked const/volatile, so with that in place, the matching never finds
const/volatile-qualified methods.

The problem is that in the DWARF, there's no indication at all whether
a method is const/volatile qualified...  For example (c++filt applied
to the linkage name for convenience):

   <2><d3>: Abbrev Number: 6 (DW_TAG_subprogram)
      <d4>   DW_AT_external    : 1
      <d4>   DW_AT_name        : (indirect string, offset: 0x3df): method
      <d8>   DW_AT_decl_file   : 1
      <d9>   DW_AT_decl_line   : 58
      <da>   DW_AT_linkage_name: (indirect string, offset: 0x5b2): S::method() const
      <de>   DW_AT_declaration : 1
      <de>   DW_AT_object_pointer: <0xe6>
      <e2>   DW_AT_sibling     : <0xec>

I see the same with both GCC and Clang.  The patch works around this
by extracting the cv qualification from the "const" and "volatile" in
the demangled name.  This will need further tweaking for "&" and
"const &" overloads, but we don't support them in the parser yet,
anyway.

The TYPE_CONST changes were necessary otherwise the comparisons in valops.c:

  if (TYPE_CONST (intype) != TYPE_FN_FIELD_CONST (f, j))
    continue;

would fail, because when both TYPE_CONST() TYPE_FN_FIELD_CONST() were
true, their values were different.

BTW, I'm recording the const/volatile-ness of methods in the
TYPE_FN_FIELD info because #1 - I'm not sure it's kosher to change the
method's type directly (vs having to call make_cv_type to create a new
type), and #2 it's what stabsread.c does:

...
	    case 'A':		/* Normal functions.  */
	      new_sublist->fn_field.is_const = 0;
	      new_sublist->fn_field.is_volatile = 0;
	      (*pp)++;
	      break;
	    case 'B':		/* `const' member functions.  */
	      new_sublist->fn_field.is_const = 1;
	      new_sublist->fn_field.is_volatile = 0;
...

After all this, this finally all works:

  print S::method(void) const
  $1 = {void (const S * const)} 0x400606 <S::method() const>
  (gdb) p S::method() const::static_var
  $2 = {i1 = 1, i2 = 2, i3 = 3}

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* c-exp.y (function_method, function_method_void): Add current
	instance flags to TYPE_INSTANCE.
	* dwarf2read.c (check_modifier): New.
	(compute_delayed_physnames): Assert that only C++ adds delayed
	physnames.  Mark fn_fields as const/volatile depending on
	physname.
	* eval.c (make_params): New type_instance_flags parameter.  Use
	it as the new type's instance flags.
	(evaluate_subexp_standard) <TYPE_INSTANCE>: Extract the instance
	flags element and pass it to make_params.
	* expprint.c (print_subexp_standard) <TYPE_INSTANCE>: Handle
	instance flags element.
	(dump_subexp_body_standard) <TYPE_INSTANCE>: Likewise.
	* gdbtypes.h: Include "enum-flags.h".
	(type_instance_flags): New enum-flags type.
	(TYPE_CONST, TYPE_VOLATILE, TYPE_RESTRICT, TYPE_ATOMIC)
	(TYPE_CODE_SPACE, TYPE_DATA_SPACE): Return boolean.
	* parse.c (operator_length_standard) <TYPE_INSTANCE>: Adjust.
	(follow_type_instance_flags): New function.
	(operator_check_standard) <TYPE_INSTANCE>: Adjust.
	* parser-defs.h (follow_type_instance_flags): Declare.
	* valops.c (value_struct_elt_for_reference): const/volatile must
	match too.

gdb/testsuite/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* gdb.base/func-static.c (S::method const, S::method volatile)
	(S::method volatile const): New methods.
	(c_s, v_s, cv_s): New instances.
	(main): Call method() on them.
	* gdb.base/func-static.exp (syntax_re, cannot_resolve_re): New variables.
	(cannot_resolve): New procedure.
	(cxx_scopes_list): Test cv methods.  Add print-scope-quote and
	print-quote-unquoted columns.
	(do_test): Test printing each scope too.
2017-09-04 20:21:16 +01:00
Pedro Alves
e68cb8e001 Handle "p 'S::method()::static_var'" (quoted) in symbol lookup
While the previous commit made "p method()::static_var" (no
single-quotes) Just Work, if users (or frontends) try wrapping the
expression with quotes, they'll get:

  (gdb) p 'S::method()::static_var'
  'S::method()::static_var' has unknown type; cast it to its declared type

even if we _do_ have debug info for that variable.  That's better than
the bogus/confusing value what GDB would print before the
stop-assuming-int patch:

  (gdb) p 'S::method()::static_var'
  $1 = 1

but I think it'd still be nice to make this case Just Work too.

In this case, due to the quoting, the C/C++ parser (c-exp.y)
interprets the whole expression/string as a single symbol name, and we
end up calling lookup_symbol on that name.  There's no debug symbol
with that fully-qualified name, but since the compiler gives the
static variable a mangled linkage name exactly like the above, it
appears in the mininal symbols:

  $ nm -A local-static | c++filt | grep static_var
  local-static:0000000000601040 d S::method()::static_var

... and that's what GDB happens to find/print.  This only happens in
C++, note, since for C the compiler uses different linkage names:

  local-static-c:0000000000601040 d static_var.1848

So while (in C++, not C) function local static variables are given a
mangled name that demangles to the same syntax that GDB
documents/expects as the way to access function local statics, there's
no global symbol in the debug info with that name at all.  The debug
info for a static local variable for a non-inline function looks like
this:

 <1><2a1>: Abbrev Number: 19 (DW_TAG_subprogram)
 ...
 <2><2f7>: Abbrev Number: 20 (DW_TAG_variable)
    <2f8>   DW_AT_name        : (indirect string, offset: 0x4e9): static_var
    <2fc>   DW_AT_decl_file   : 1
    <2fd>   DW_AT_decl_line   : 64
    <2fe>   DW_AT_type        : <0x25>
    <302>   DW_AT_location    : 9 byte block: 3 40 10 60 0 0 0 0 0      (DW_OP_addr: 601040)

and for an inline function, it looks like this (linkage name run
through c++filt for convenience):

 <2><21b>: Abbrev Number: 16 (DW_TAG_variable)
    <21c>   DW_AT_name        : (indirect string, offset: 0x21a): static_var
    <220>   DW_AT_decl_file   : 1
    <221>   DW_AT_decl_line   : 48
    <222>   DW_AT_linkage_name: (indirect string, offset: 0x200): S::inline_method()::static_var
    <226>   DW_AT_type        : <0x25>
    <22a>   DW_AT_external    : 1
    <22a>   DW_AT_location    : 9 byte block: 3 a0 10 60 0 0 0 0 0      (DW_OP_addr: 6010a0)

(The inline case makes the variable external so that the linker can
merge the different inlined copies.  It seems like GCC never outputs
the linkage name for non-extern globals.)

When we read the DWARF, we record the static_var variable as a regular
variable of the containing function's block.  This makes stopping in
the function and printing the variable as usual.  The variable just so
happens to have a memory address as location.

So one way to make "p 'S::method()::static_var'" work would be to
record _two_ copies of the symbols for these variables.  One in the
function's scope/block, with "static_var" as name, as we currently do,
and another in the static or global blocks (depending on whether the
symbol is external), with a fully-qualified name.  I wrote a prototype
patch for that, and it works.  For the non-inline case above, since
the debug info doesn't point to the linkage same, that patch built the
physname of the static local variable as the concat of the physname of
the containing function, plus "::", plus the variable's name.  We
could make that approach work for C too, though it kind of feels
awkward to record fake symbol names like that in C.

The other approach I tried is to change the C++ symbol lookup routines
instead.  This is the approach this commit takes.  We can already
lookup up symbol in namespaces and classes, so this feels like a good
fit, and was easy enough.  The advantage is that this doesn't require
recording extra symbols.

The test in gdb.cp/m-static.exp that exposed the need for this is
removed, since the same functionality is now covered by
gdb.cp/local-static.exp.

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* cp-namespace.c (cp_search_static_and_baseclasses): Handle
	function/method scopes; lookup the nested name as a function local
	static variable.

gdb/testsuite/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* gdb.base/local-static.exp: Also test with
	class::method::variable wholly quoted.
	* gdb.cp/m-static.exp (class::method::variable): Remove test.
2017-09-04 20:21:16 +01:00
Pedro Alves
858be34c5a Handle "p S::method()::static_var" in the C++ parser
This commit makes "print S::method()::static_var" actually find the
debug symbol for static_var.  Currently, you get:

  (gdb) print S::method()::static_var
  A syntax error in expression, near `'.

Quoting the whole string would seemingly work before the previous
patch that made GDB stop assuming int for no-debug-info variables:

  (gdb) p 'S::method()::static_var'
  $1 = 1

... except that's incorrect output, because:

  (gdb) ptype 'S::method()::static_var'
  type = <data variable, no debug info>

The way to make it work correctly currently is by quoting the
function/method part, like this:

  (gdb) print 'S::method()'::static_var
  $1 = {i1 = 1, i2 = 2, i3 = 3}
  (gdb) ptype 'S::method()'::static_var
  type = struct aggregate {
      int i1;
      int i2;
      int i3;
  }

At least after the "stop assuming int" patch, this is what we
now get:

  (gdb) p 'S::method()::static_var'
  'S::method()::static_var' has unknown type; cast it to its declared type
  (gdb) p (struct aggregate) 'S::method()::static_var'
  $1 = {i1 = 1, i2 = 2, i3 = 3}

However, IMO, users shouldn't really have to care about any of this.
GDB should Just Work, without quoting, IMO.

So here's a patch that implements support for that in the C++ parser.
With this patch, you now get:

  (gdb) p S::method()::S_M_s_var_aggregate
  $1 = {i1 = 1, i2 = 2, i3 = 3}
  (gdb) ptype S::method()::S_M_s_var_aggregate
  type = struct aggregate {
      int i1;
      int i2;
      int i3;
  }

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	(%type <voidval>): Add function_method.
	* c-exp.y (exp): New production for calls with no arguments.
	(function_method, function_method_void_or_typelist): New
	productions.
	(exp): New production for "method()::static_var".
	* eval.c (evaluate_subexp_standard): Handle OP_FUNC_STATIC_VAR.
	* expprint.c (print_subexp_standard, dump_subexp_body_standard):
	Handle OP_FUNC_STATIC_VAR.
	* parse.c (operator_length_standard):
	Handle OP_FUNC_STATIC_VAR.
	* std-operator.def (OP_FUNC_STATIC_VAR): New.

gdb/testsuite/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* gdb.base/local-static.c: New.
	* gdb.base/local-static.cc: New.
	* gdb.base/local-static.exp:  New.
2017-09-04 20:21:15 +01:00
Pedro Alves
dd5901a6a5 Eliminate UNOP_MEMVAL_TLS
Since minsym references now go via OP_VAR_MSYM_VALUE, UNOP_MEMVAL_TLS
is no longer used anywhere.

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* eval.c (evaluate_subexp_standard): Remove UNOP_MEMVAL_TLS
	handling.
	* expprint.c (print_subexp_standard, dump_subexp_body_standard):
	Ditto.
	* parse.c (operator_length_standard, operator_check_standard):
	Ditto.
	* std-operator.def (UNOP_MEMVAL_TLS): Delete.
2017-09-04 20:21:15 +01:00
Pedro Alves
46a4882b3c Stop assuming no-debug-info variables have type int
An earlier commit made GDB no longer assume no-debug-info functions
return int.  This commit gives the same treatment to variables.

Currently, you can end misled by GDB over output like this:

  (gdb) p var
  $1 = -1
  (gdb) p /x var
  $2 = 0xffffffff

until you realize that GDB is assuming that the variable is an "int",
because:

  (gdb) ptype var
  type = <data variable, no debug info>

You may try to fix it by casting, but that doesn't really help:

  (gdb) p /x (unsigned long long) var
  $3 = 0xffffffffffffffff            # incorrect
         ^^

That's incorrect output, because the variable was defined like this:

  uint64_t var = 0x7fffffffffffffff;
                   ^^

What happened is that with the cast, GDB did an int -> 'unsigned long
long' conversion instead of reinterpreting the variable as the cast-to
type.  To get at the variable properly you have to reinterpret the
variable's address manually instead, with either:

  (gdb) p /x *(unsigned long long *) &var
  $4 = 0x7fffffffffffffff
  (gdb) p /x {unsigned long long} &var
  $5 = 0x7fffffffffffffff

After this commit GDB does it for you.  This is what you'll get
instead:

  (gdb) p var
  'var' has unknown type; cast it to its declared type
  (gdb) p /x (unsigned long long) var
  $1 = 0x7fffffffffffffff

As in the functions patch, the "compile" machinery doesn't currently
have the cast-to type handy, so it continues assuming no-debug
variables have int type, though now at least it warns.

The change to gdb.cp/m-static.exp deserves an explanation:

 - gdb_test "print 'gnu_obj_1::method()::sintvar'" "\\$\[0-9\]+ = 4" \
 + gdb_test "print (int) 'gnu_obj_1::method()::sintvar'" "\\$\[0-9\]+ = 4" \

That's printing the "sintvar" function local static of the
"gnu_obj_1::method()" method.

The problem with that test is that that "'S::method()::static_var'"
syntax doesn't really work in C++ as you'd expect.  The way to make it
work correctly currently is to quote the method part, not the whole
expression, like:

  (gdb) print 'gnu_obj_1::method()'::sintvar

If you wrap the whole expression in quotes, like in m-static.exp, what
really happens is that the parser considers the whole string as a
symbol name, but there's no debug symbol with that name.  However,
local statics have linkage and are given a mangled name that demangles
to the same string as the full expression, so that's what GDB prints.
After this commit, and without the cast, the print in m-static.exp
would error out saying that the variable has unknown type:

  (gdb) p 'gnu_obj_1::method()::sintvar'
  'gnu_obj_1::method()::sintvar' has unknown type; cast it to its declared type

TBC, if currently (even before this series) you try to print any
function local static variable of type other than int, you'll get
bogus results.  You can see that with m-static.cc as is, even.
Printing the "svar" local, which is a boolean (1 byte) still prints as
"int" (4 bytes):

  (gdb) p 'gnu_obj_1::method()::svar'
  $1 = 1
  (gdb) ptype 'gnu_obj_1::method()::svar'
  type = <data variable, no debug info>

This probably prints some random bogus value on big endian machines.

If 'svar' was of some aggregate type (etc.) we'd still print it as
int, so the problem would have been more obvious...  After this
commit, you'll get instead:

  (gdb) p 'gnu_obj_1::method()::svar'
  'gnu_obj_1::method()::svar' has unknown type; cast it to its declared type

... so at least GDB is no longer misleading.  Making GDB find the real
local static debug symbol is the subject of the following patches.  In
the end, it'll all "Just Work".

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* ax-gdb.c: Include "typeprint.h".
	(gen_expr_for_cast): New function.
	(gen_expr) <OP_CAST, OP_CAST_TYPE>: Use it.
	<OP_VAR_VALUE, OP_MSYM_VAR_VALUE>: Error out if the variable's
	type is unknown.
	* dwarf2read.c (new_symbol_full): Fallback to int instead of
	nodebug_data_symbol.
	* eval.c: Include "typeprint.h".
	(evaluate_subexp_standard) <OP_VAR_VALUE, OP_VAR_MSYM_VALUE>:
	Error out if symbol has unknown type.
	<UNOP_CAST, UNOP_CAST_TYPE>: Common bits factored out to
	evaluate_subexp_for_cast.
	(evaluate_subexp_for_address, evaluate_subexp_for_sizeof): Handle
	OP_VAR_MSYM_VALUE.
	(evaluate_subexp_for_cast): New function.
	* gdbtypes.c (init_nodebug_var_type): New function.
	(objfile_type): Use it to initialize types of variables with no
	debug info.
	* typeprint.c (error_unknown_type): New.
	* typeprint.h (error_unknown_type): New declaration.
	* compile/compile-c-types.c (convert_type_basic): Handle
	TYPE_CODE_ERROR; warn and fallback to int for variables with
	unknown type.

gdb/testsuite/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* gdb.asm/asm-source.exp: Add casts to int.
	* gdb.base/nodebug.c (dataglobal8, dataglobal32_1, dataglobal32_2)
	(dataglobal64_1, dataglobal64_2): New globals.
	* gdb.base/nodebug.exp: Test different expressions involving the
	new globals, with print, whatis and ptype.  Add casts to int.
	* gdb.base/solib-display.exp: Add casts to int.
	* gdb.compile/compile-ifunc.exp: Expect warning.  Add cast to int.
	* gdb.cp/m-static.exp: Add cast to int.
	* gdb.dwarf2/dw2-skip-prologue.exp: Add cast to int.
	* gdb.threads/tls-nodebug.exp: Check that gdb errors out printing
	tls variable with no debug info without a cast.  Test with a cast
	to int too.
	* gdb.trace/entry-values.exp: Add casts.
2017-09-04 20:21:15 +01:00
Pedro Alves
fe13dfecbf evaluate_subexp_standard: Factor out OP_VAR_VALUE handling.
A following patch will want to call the new evaluate_var_value
function in another spot.

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* eval.c (evaluate_var_value): New function, factored out from ...
	(evaluate_subexp_standard): ... here.
2017-09-04 20:21:14 +01:00
Pedro Alves
d008ee2156 evaluate_subexp_standard: Remove useless assignments
gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* eval.c (evaluate_subexp_standard) <UNOP_COMPLEMENT, UNOP_ADDR>:
	Remove useless assignments to 'op'.
2017-09-04 20:21:14 +01:00
Pedro Alves
827d0c517e evaluate_subexp_standard: Eliminate one goto
A following patch will want to factor out a bit of
evaluate_subexp_standard, and it'd be handy to reuse the code under the
"nosideret:" label there too.  This commits moves it to a separate
function as preparation for that.

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* eval.c (eval_skip_value): New function.
	(evaluate_subexp_standard): Use it.
2017-09-04 20:21:14 +01:00
Pedro Alves
2c5a2be190 Make ptype/whatis print function name of functions with no debug info too
The patch to make GDB stop assuming functions return int left GDB with
an inconsistency.  While with normal expression evaluation the
"unknown return type" error shows the name of the function that misses
debug info:

  (gdb) p getenv ("PATH")
  'getenv' has unknown return type; cast the call to its declared return type
   ^^^^^^

which is handy in more complicated expressions, "ptype" does not:

  (gdb) ptype getenv ("PATH")
  function has unknown return type; cast the call to its declared return type
  ^^^^^^^^

This commit builds on the new OP_VAR_MSYM_VALUE to fix it, by making
OP_FUNCALL extract the function name from the symbol stored in
OP_VAR_VALUE/OP_VAR_MSYM_VALUE.  We now get the same error in "print"
vs "ptype":

  (gdb) ptype getenv()
  'getenv' has unknown return type; cast the call to its declared return type
  (gdb) p getenv()
  'getenv' has unknown return type; cast the call to its declared return type

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* eval.c (evaluate_subexp_standard): <OP_FUNCALL>: Extract
	function name from symbol/minsym and pass it to
	error_call_unknown_return_type.

gdb/testsuite/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* gdb.base/nodebug.exp: Test that ptype's error about functions
	with unknown return type includes the function name too.
2017-09-04 20:21:14 +01:00
Pedro Alves
74ea4be48e Introduce OP_VAR_MSYM_VALUE
The previous patch left GDB with an inconsistency.  While with normal
expression evaluation the "unknown return type" error shows the name
of the function that misses debug info:

  (gdb) p getenv ("PATH")
  'getenv' has unknown return type; cast the call to its declared return type
   ^^^^^^

which can by handy in more complicated expressions, "ptype" does not:

  (gdb) ptype getenv ("PATH")
  function has unknown return type; cast the call to its declared return type
  ^^^^^^^^

This commit is a step toward fixing it.

The problem is that while evaluating the expression above, we have no
reference to the minimal symbol where we could extract the name from.
This is because the resulting expression tree has no reference to the
minsym at all.  During parsing, the type and address of the minsym are
extracted and an UNOP_MEMVAL / UNOP_MEMVAL_TLS operator is generated
(see write_exp_elt_msym).  With "set debug expression", here's what
you see:

            0  OP_FUNCALL            Number of args: 0
            3    UNOP_MEMVAL           Type @0x565334a51930 (<text variable, no debug info>)
            6      OP_LONG               Type @0x565334a51c60 (__CORE_ADDR), value 140737345035648 (0x7ffff7751d80)

The "print" case finds the function name, because
call_function_by_hand looks up the function by address again.
However, for "ptype", we don't reach that code, because obviously we
don't really call the function.

Unlike minsym references, references to variables with debug info have
a pointer to the variable's symbol in the expression tree, with
OP_VAR_VALUE:

  (gdb) ptype main()
  ...
            0  OP_FUNCALL            Number of args: 0
            3    OP_VAR_VALUE          Block @0x0, symbol @0x559bbbd9b358 (main(int, char**))
  ...

so I don't see why do minsyms need to be different.  So to prepare for
fixing the missing function name issue, this commit adds a new
OP_VAR_MSYM_VALUE operator that mimics OP_VAR_VALUE, except that it's
for minsyms instead of debug symbols.  For infcalls, we now get
expressions like these:

            0  OP_FUNCALL            Number of args: 0
            3    OP_VAR_MSYM_VALUE     Objfile @0x1e41bf0, msymbol @0x7fffe599b000 (getenv)

In the following patch, we'll make OP_FUNCALL extract the function
name from the symbol stored in OP_VAR_VALUE/OP_VAR_MSYM_VALUE.

OP_VAR_MSYM_VALUE will be used more in a later patch in the series
too.

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* ada-lang.c (resolve_subexp): Handle OP_VAR_MSYM_VALUE.
	* ax-gdb.c (gen_msym_var_ref): New function.
	(gen_expr): Handle OP_VAR_MSYM_VALUE.
	* eval.c (evaluate_var_msym_value): New function.
	* eval.c (evaluate_subexp_standard): Handle OP_VAR_MSYM_VALUE.
	<OP_FUNCALL>: Extract function name from symbol/minsym and pass it
	to call_function_by_hand.
	* expprint.c (print_subexp_standard, dump_subexp_body_standard):
	Handle OP_VAR_MSYM_VALUE.
	(union exp_element) <msymbol>: New field.
	* minsyms.h (struct type): Forward declare.
	(find_minsym_type_and_address): Declare.
	* parse.c (write_exp_elt_msym): New function.
	(write_exp_msymbol): Delete, refactored as ...
	(find_minsym_type_and_address): ... this new function.
	(write_exp_msymbol): Reimplement using OP_VAR_MSYM_VALUE.
	(operator_length_standard, operator_check_standard): Handle
	OP_VAR_MSYM_VALUE.
	* std-operator.def (OP_VAR_MSYM_VALUE): New.
2017-09-04 20:21:13 +01:00
Pedro Alves
7022349d5c Stop assuming no-debug-info functions return int
The fact that GDB defaults to assuming that functions return int, when
it has no debug info for the function has been a recurring source of
user confusion.  Recently this came up on the errno pretty printer
discussions.  Shortly after, it came up again on IRC, with someone
wondering why does getenv() in GDB return a negative int:

  (gdb) p getenv("PATH")
  $1 = -6185

This question (with s/getenv/random-other-C-runtime-function) is a FAQ
on IRC.

The reason for the above is:

 (gdb) p getenv
 $2 = {<text variable, no debug info>} 0x7ffff7751d80 <getenv>
 (gdb) ptype getenv
 type = int ()

... which means that GDB truncated the 64-bit pointer that is actually
returned from getent to 32-bit, and then sign-extended it:

 (gdb) p /x -6185
 $6 = 0xffffe7d7

The workaround is to cast the function to the right type, like:

 (gdb) p ((char *(*) (const char *)) getenv) ("PATH")
 $3 = 0x7fffffffe7d7 "/usr/local/bin:/"...

IMO, we should do better than this.

I see the "assume-int" issue the same way I see printing bogus values
for optimized-out variables instead of "<optimized out>" -- I'd much
rather that the debugger tells me "I don't know" and tells me how to
fix it than showing me bogus misleading results, making me go around
tilting at windmills.

If GDB prints a signed integer when you're expecting a pointer or
aggregate, you at least have some sense that something is off, but
consider the case of the function actually returning a 64-bit integer.
For example, compile this without debug info:

 unsigned long long
 function ()
 {
   return 0x7fffffffffffffff;
 }

Currently, with pristine GDB, you get:

 (gdb) p function ()
 $1 = -1                      # incorrect
 (gdb) p /x function ()
 $2 = 0xffffffff              # incorrect

maybe after spending a few hours debugging you suspect something is
wrong with that -1, and do:

 (gdb) ptype function
 type = int ()

and maybe, just maybe, you realize that the function actually returns
unsigned long long.  And you try to fix it with:

(gdb) p /x (unsigned long long) function ()
 $3 = 0xffffffffffffffff      # incorrect

... which still produces the wrong result, because GDB simply applied
int to unsigned long long conversion.  Meaning, it sign-extended the
integer that it extracted from the return of the function, to 64-bits.

and then maybe, after asking around on IRC, you realize you have to
cast the function to a pointer of the right type, and call that.  It
won't be easy, but after a few missteps, you'll get to it:

.....  (gdb) p /x ((unsigned long long(*) ()) function) ()
 $666 = 0x7fffffffffffffff             # finally! :-)


So to improve on the user experience, this patch does the following
(interrelated) things:

 - makes no-debug-info functions no longer default to "int" as return
   type.  Instead, they're left with NULL/"<unknown return type>"
   return type.

    (gdb) ptype getenv
    type = <unknown return type> ()

 - makes calling a function with unknown return type an error.

    (gdb) p getenv ("PATH")
    'getenv' has unknown return type; cast the call to its declared return type

 - and then to make it easier to call the function, makes it possible
   to _only_ cast the return of the function to the right type,
   instead of having to cast the function to a function pointer:

    (gdb) p (char *) getenv ("PATH")                      # now Just Works
    $3 = 0x7fffffffe7d7 "/usr/local/bin:/"...

    (gdb) p ((char *(*) (const char *)) getenv) ("PATH")  # continues working
    $4 = 0x7fffffffe7d7 "/usr/local/bin:/"...

   I.e., it makes GDB default the function's return type to the type
   of the cast, and the function's parameters to the type of the
   arguments passed down.

After this patch, here's what you'll get for the "unsigned long long"
example above:

 (gdb) p function ()
 'function' has unknown return type; cast the call to its declared return type
 (gdb) p /x (unsigned long long) function ()
 $4 = 0x7fffffffffffffff     # correct!

Note that while with "print" GDB shows the name of the function that
has the problem:

  (gdb) p getenv ("PATH")
  'getenv' has unknown return type; cast the call to its declared return type

which can by handy in more complicated expressions, "ptype" does not:

  (gdb) ptype getenv ("PATH")
  function has unknown return type; cast the call to its declared return type

This will be fixed in the next patch.

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* ada-lang.c (ada_evaluate_subexp) <TYPE_CODE_FUNC>: Don't handle
	TYPE_GNU_IFUNC specially here.  Throw error if return type is
	unknown.
	* ada-typeprint.c (print_func_type): Handle functions with unknown
	return type.
	* c-typeprint.c (c_type_print_base): Handle functions and methods
	with unknown return type.
	* compile/compile-c-symbols.c (convert_symbol_bmsym)
	<mst_text_gnu_ifunc>: Use nodebug_text_gnu_ifunc_symbol.
	* compile/compile-c-types.c: Include "objfiles.h".
	(convert_func): For functions with unknown return type, warn and
	default to int.
	* compile/compile-object-run.c (compile_object_run): Adjust call
	to call_function_by_hand_dummy.
	* elfread.c (elf_gnu_ifunc_resolve_addr): Adjust call to
	call_function_by_hand.
	* eval.c (evaluate_subexp_standard): Adjust calls to
	call_function_by_hand.  Handle functions and methods with unknown
	return type.  Pass expect_type to call_function_by_hand.
	* f-typeprint.c (f_type_print_base): Handle functions with unknown
	return type.
	* gcore.c (call_target_sbrk): Adjust call to
	call_function_by_hand.
	* gdbtypes.c (objfile_type): Leave nodebug text symbol with NULL
	return type instead of int.  Make nodebug_text_gnu_ifunc_symbol be
	an integer address type instead of nodebug.
	* guile/scm-value.c (gdbscm_value_call): Adjust call to
	call_function_by_hand.
	* infcall.c (error_call_unknown_return_type): New function.
	(call_function_by_hand): New "default_return_type" parameter.
	Pass it down.
	(call_function_by_hand_dummy): New "default_return_type"
	parameter.  Use it instead of defaulting to int.  If there's no
	default and the return type is unknown, throw an error.  If
	there's a default return type, and the called function has no
	debug info, then assume the function is prototyped.
	* infcall.h (call_function_by_hand, call_function_by_hand_dummy):
	New "default_return_type" parameter.
	(error_call_unknown_return_type): New declaration.
	* linux-fork.c (call_lseek): Cast return type of lseek.
	(inferior_call_waitpid, checkpoint_command): Adjust calls to
	call_function_by_hand.
	* linux-tdep.c (linux_infcall_mmap, linux_infcall_munmap): Adjust
	calls to call_function_by_hand.
	* m2-typeprint.c (m2_procedure): Handle functions with unknown
	return type.
	* objc-lang.c (lookup_objc_class, lookup_child_selector)
	(value_nsstring, print_object_command): Adjust calls to
	call_function_by_hand.
	* p-typeprint.c (pascal_type_print_varspec_prefix): Handle
	functions with unknown return type.
	(pascal_type_print_func_varspec_suffix): New function.
	(pascal_type_print_varspec_suffix) <TYPE_CODE_FUNC,
	TYPE_CODE_METHOD>: Use it.
	* python/py-value.c (valpy_call): Adjust call to
	call_function_by_hand.
	* rust-lang.c (rust_evaluate_funcall): Adjust call to
	call_function_by_hand.
	* valarith.c (value_x_binop, value_x_unop): Adjust calls to
	call_function_by_hand.
	* valops.c (value_allocate_space_in_inferior): Adjust call to
	call_function_by_hand.
	* typeprint.c (type_print_unknown_return_type): New function.
	* typeprint.h (type_print_unknown_return_type): New declaration.

gdb/testsuite/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* gdb.base/break-main-file-remove-fail.exp (test_remove_bp): Cast
	return type of munmap in infcall.
	* gdb.base/break-probes.exp: Cast return type of foo in infcall.
	* gdb.base/checkpoint.exp: Simplify using for loop.  Cast return
	type of ftell in infcall.
	* gdb.base/dprintf-detach.exp (dprintf_detach_test): Cast return
	type of getpid in infcall.
	* gdb.base/infcall-exec.exp: Cast return type of execlp in
	infcall.
	* gdb.base/info-os.exp: Cast return type of getpid in infcall.
	Bail on failure to extract the pid.
	* gdb.base/nodebug.c: #include <stdint.h>.
	(multf, multf_noproto, mult, mult_noproto, add8, add8_noproto):
	New functions.
	* gdb.base/nodebug.exp (test_call_promotion): New procedure.
	Change expected output of print/whatis/ptype with functions with
	no debug info.  Test all supported languages.  Call
	test_call_promotion.
	* gdb.compile/compile.exp: Adjust expected output to expect
	warning.
	* gdb.threads/siginfo-threads.exp: Likewise.
2017-09-04 20:21:13 +01:00
Pedro Alves
54990598c4 Fix calling prototyped functions via function pointers
Calling a prototyped function via a function pointer with the right
prototype doesn't work correctly, if the called function requires
argument coercion...  Like, e.g., with:

  float mult (float f1, float f2) { return f1 * f2; }

  (gdb) p mult (2, 3.5)
  $1 = 7
  (gdb) p ((float (*) (float, float)) mult) (2, 3.5)
  $2 = 0

both calls should have returned the same, of course.  The problem is
that GDB misses marking the type of the function pointer target as
prototyped...

Without the fix, the new test fails like this:

 (gdb) p ((int (*) (float, float)) t_float_values2)(3.14159,float_val2)
 $30 = 0
 (gdb) FAIL: gdb.base/callfuncs.exp: p ((int (*) (float, float)) t_float_values2)(3.14159,float_val2)

gdb/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* gdbtypes.c (lookup_function_type_with_arguments): Mark function
	types with more than one parameter as prototyped.

gdb/testsuite/ChangeLog:
2017-09-04  Pedro Alves  <palves@redhat.com>

	* gdb.base/callfuncs.exp (do_function_calls): New parameter
	"prototypes".  Test calling float functions via prototyped and
	unprototyped function pointers.
	(perform_all_tests): New parameter "prototypes".  Pass it down.
	(top level): Pass down "prototypes" parameter to
	perform_all_tests.
2017-09-04 20:21:13 +01:00
Simon Marchi
34d16ea2a1 gdb.base/commands.exp: Test loop_break and loop_continue in nested loops
This patch improves the loop_break and loop_continue tests to verify
that they work as expected when multiple loops are nested (they affect
the inner loop).

gdb/testsuite/ChangeLog:

	* gdb.base/commands.exp (loop_break_test, loop_continue_test):
	Test with nested loops.
2017-09-04 21:19:17 +02:00