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5293 commits

Author SHA1 Message Date
Jan Kratochvil
7e67715dd3 [testsuite patch] Fix new FAIL: py-frame.exp: test Frame.read_register(rip)
for x86_64 -m32 run one gets:

+FAIL: gdb.python/py-frame.exp: test Frame.read_register(rip)

I do not have x32 OS here but the %rip test should PASS there I think.

On Sun, 11 Jan 2015 14:58:06 +0100, Yao Qi wrote:
With your patch applied, this test is skipped on 'x86_64 -m32'.  I
prefer to increasing the test coverage, so how about extending the test
for 'x86_64 -m32'?  I mean test Frame.read_register(eip)...

gdb/testsuite/ChangeLog
2015-01-12  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.python/py-frame.exp (test Frame.read_register(rip)): Use
	is_amd64_regs_target and is_x86_like_target.
2015-01-12 11:02:46 +01:00
Doug Evans
f2e0d4b4eb Require numeric attributes to specify the form.
gdb/testsuite/ChangeLog:

	* lib/dwarf.exp (Dwarf): Flag an error if a numeric attribute value
	is given without an explicit form.
	* gdb.dwarf2/arr-subrange.exp: Specify forms for all numeric
	attributes.
	* gdb.dwarf/corrupt.exp: Ditto.
	* gdb.dwarf2/enum-type.exp: Ditto.
	* gdb.trace/entry-values.exp: Ditto.
	* gdb.trace/unavailable-dwarf-piece.exp: Ditto.
2015-01-11 15:45:43 -08:00
Doug Evans
439250fbac PR gdb/15830
gdb/ChangeLog:

	PR gdb/15830
	* NEWS: The "maint demangle" command is renamed as "demangle".
	* demangle.c: #include cli/cli-utils.h, language.h.
	(demangle_command): New function.
	(_initialize_demangle): Add new command "demangle".
	* maint.c (maintenance_demangle): Stub out.
	(_initialize_maint_cmds): Update help text for "maint demangle",
	and mark as deprecated.

gdb/doc/ChangeLog:

	* gdb.texinfo (Debugging C Plus Plus): Mention "demangle".
	(Symbols): Ditto.
	(Maintenance Commands): Delete docs for "maint demangle".

gdb/testsuite/ChangeLog:

	* gdb.base/maint.exp: Remove references to "maint demangle".
	* gdb.cp/demangle.exp: Update.  "maint demangle" -> "demangle".
	Add tests for explicitly specifying language to demangle.
	* gdb.dlang/demangle.exp: Ditto.
2015-01-11 14:06:34 -08:00
Pedro Alves
ede9f622af add non-stop test that stresses thread starvation issues
This commit adds a non-stop mode test originally inspired by
signal-while-stepping-over-bp-other-thread.exp, that exposes the
thread starvation issues fixed by the previous patches.  It sets a set
of threads stepping in parallel, and has one of them get a signal.
Without the previous fixes, this would fail with timeouts.

gdb/testsuite/
2015-01-09  Pedro Alves  <palves@redhat.com>

	* gdb.threads/non-stop-fair-events.c: New file.
	* gdb.threads/non-stop-fair-events.exp: New file.
2015-01-09 14:44:42 +00:00
Pedro Alves
a7b796db4f watch_thread_num.exp and targets with fairer event reporting
This patch fixes the watch_thread_num.exp test to work when the target
is better at making event handling be fair among threads.

I wrote patches that make GDB native and GDBserver event handling
fairer between threads.  That is, if threads A and B both
simultaneously trigger some debug event, GDB will pick either A or B
at random, rather than always handling the event of A first.  There's
code for that in the Linux backends (gdb and gdbserver) already, but
it can be improved, and only works in all-stop mode.

With those fixes in place, I found that the watch_thread_num.exp would
often time out.  The problem is that the test only works _because_
event handling isn't as fair as intended.  With the fairness fixes,
the test falls victim of PR10116 (gdb drops watchpoints on
multi-threaded apps) quite often.

To expand on the PR10116 reference, consider that stop events are
serialized to GDB core, through target_wait.  Say a thread-specific
watchpoint as set on thread A.  When the "right" thread and some other
"wrong" thread both trigger a watchpoint simultaneously, the target
may report the "wrong" thread's hit to GDB first (thread B).  When
handling that event, GDB notices the watchpoint is for another thread,
and so shouldn't cause a user-visible stop.  On resume, GDB saves the
now current value of the watched expression.  Afterwards, the "right"
thread (thread A) reports its watchpoint trigger.  But the watched
value hasn't changed since GDB last saved it, and so GDB doesn't
report the watchpoint hit to the user.

The way the test is written, the watchpoint is associated with the
first thread that happens to report an event.  It happens that GDB is
processing events much more often for one of the threads, which
usually will be that same first thread.

Hacking the test with "set debug infrun 1", we see exactly that:

$ grep  "infrun.*\[Thread.*," testsuite/gdb.log | sort | uniq -c | sort -nr
     70 infrun:   8798 [Thread 8798],
     37 infrun:   8798 [Thread 8802],
     36 infrun:   8798 [Thread 8804],
     36 infrun:   8798 [Thread 8803],
     35 infrun:   8798 [Thread 8805],
     34 infrun:   8798 [Thread 8806],

The first column shows the number of times the target reported an
event for that thread, from:

 infrun: target_wait (-1, status) =
 infrun:   8798 [Thread 8798],
 infrun:   status->kind = stopped, signal = GDB_SIGNAL_TRAP

This masks out the PR10116 issue.

However, if the target is better at giving equal priority to all
threads, the PR10116 issue happens often, so it may take quite a while
for the right thread to be the first to report its watchpoint event
just after the memory being watched really changed, resulting in test
time outs.

Here's the number of events handled for each thread on a gdbserver run
with the event fairness patches:

$ grep  "infrun.*\[Thread.*," gdb.log | sort | uniq -c
   2961 infrun:   13591 [Thread 13591],
   2956 infrun:   13591 [Thread 13595],
   2941 infrun:   13591 [Thread 13596],
   2932 infrun:   13591 [Thread 13597],
   2905 infrun:   13591 [Thread 13598],
   2891 infrun:   13591 [Thread 13599],

Note how the number of events is much higher.  The test routinely
takes over 10 seconds to finish on my machine rather than under a
second as with unpatched gdbserver, when it succeeds, but often it'll
fail with timeouts too.

So to make the test robust, this patch switches the tests to using
"awatch" instead of "watch", as access watchpoints don't care about
the watchpoint's "old value".  With this, the test always finishes
quickly, and we can even bump the number of threads concurrently
writting to the shared variable, to have better assurance we're really
testing the case of the "wrong" thread triggering a watchpoint.

Here's the number of events I see for each thread on a run on my
machine, with a gdbserver patched with the event fairness series:

$ grep  "infrun.*\[Thread.*," testsuite/gdb.log | sort | uniq -c
      5 infrun:   5298 [Thread 5302],
      4 infrun:   5298 [Thread 5303],
      4 infrun:   5298 [Thread 5304],
      4 infrun:   5298 [Thread 5305],
      4 infrun:   5298 [Thread 5306],
      4 infrun:   5298 [Thread 5307],
      4 infrun:   5298 [Thread 5308],
      4 infrun:   5298 [Thread 5309],
      4 infrun:   5298 [Thread 5310],
      4 infrun:   5298 [Thread 5311],
      4 infrun:   5298 [Thread 5312],
      4 infrun:   5298 [Thread 5313],
      4 infrun:   5298 [Thread 5314],
      4 infrun:   5298 [Thread 5315],
      4 infrun:   5298 [Thread 5316],

gdb/testsuite/
2015-01-09  Pedro Alves  <palves@redhat.com>

	* gdb.base/annota1.exp (thread_test): Use srcfile and binfile from
	the global scope.  Set a breakpoint after all threads are started
	rather than stepping over two source lines.  Expect the prompt.
	* gdb.base/watch_thread_num.c (threads_started_barrier): New
	global.
	(NUM): Now 15.
	(main): Use threads_started_barrier to wait for all threads to
	start.  Main thread no longer calls thread_function.  Exit after
	180 seconds.
	(loop): New function.
	(thread_function): Wait on threads_started_barrier barrier.  Call
	'loop' at each iteration.
	* gdb.base/watch_thread_num.exp: Continue to breakpoint after all
	threads have started, instead of hardcoding number of "next"
	steps.  Use an access watchpoint instead of a write watchpoint.
2015-01-09 14:39:41 +00:00
Pedro Alves
9665ffdd59 gdb.threads/{siginfo-thread.c,watchthreads-reorder.c,ia64-sigill.c} races with GDB
These three test all spawn a few threads and then send a SIGSTOP to
their parent GDB in order to pause it while the new threads set things
up for the test.  With a GDB patch that changes the inferior thread's
scheduling a bit, I sometimes see:

  FAIL: gdb.threads/siginfo-threads.exp: catch signal 0 (timeout)
  ...
  FAIL: gdb.threads/watchthreads-reorder.exp: reorder1: continue a (timeout)
  ...
  FAIL: gdb.threads/ia64-sigill.exp: continue (timeout)
  ...

The issue is that the test program stops GDB before it had a chance of
processing the new thread's clone event:

  (gdb) PASS: gdb.threads/siginfo-threads.exp: get pid
  continue
  Continuing.
  Stopping GDB PID 21541.
  Waiting till the threads initialize their TIDs.
  FAIL: gdb.threads/siginfo-threads.exp: catch signal 0 (timeout)

On Linux (at least), new threads start stopped, and the debugger must
resume them.  The fix is to make the test program wait for the new
threads to be running before stopping GDB.

gdb/testsuite/
2015-01-09  Pedro Alves  <palves@redhat.com>

	* gdb.threads/ia64-sigill.c (threads_started_barrier): New global.
	(thread_func): Wait on barrier.
	(main): Wait for all threads to start before stopping GDB.
	* gdb.threads/siginfo-threads.c (threads_started_barrier): New
	global.
	(thread1_func, thread2_func): Wait on barrier.
	(main): Wait for all threads to start before stopping GDB.
	* gdb.threads/watchthreads-reorder.c (threads_started_barrier):
	New global.
	(thread1_func, thread2_func): Wait on barrier.
	(main): Wait for all threads to start before stopping GDB.
2015-01-09 13:58:29 +00:00
Pedro Alves
c945a99f01 Test attaching to a program that constantly spawns short-lived threads
Before the previous fixes, on Linux, this would trigger several
different problems, like:

 [New LWP 27106]
 [New LWP 27047]
 warning: unable to open /proc file '/proc/-1/status'
 [New LWP 27813]
 [New LWP 27869]
 warning: Can't attach LWP 11962: No child processes
 Warning: couldn't activate thread debugging using libthread_db: Cannot find new threads: debugger service failed
 warning: Unable to find libthread_db matching inferior's thread library, thread debugging will not be available.

gdb/testsuite/
2015-01-09  Pedro Alves  <palves@redhat.com>

	* gdb.threads/attach-many-short-lived-threads.c: New file.
	* gdb.threads/attach-many-short-lived-threads.exp: New file.
2015-01-09 11:44:04 +00:00
Pedro Alves
c1a747c109 Linux: Skip thread_db thread event reporting if PTRACE_EVENT_CLONE is supported
[A test I wrote stumbled on a libthread_db issue related to thread
event breakpoints.  See glibc PR17705:
 [nptl_db: stale thread create/death events if debugger detaches]
 https://sourceware.org/bugzilla/show_bug.cgi?id=17705

This patch avoids that whole issue by making GDB stop using thread
event breakpoints in the first place, which is good for other reasons
as well, anyway.]

Before PTRACE_EVENT_CLONE (Linux 2.6), the only way to learn about new
threads in the inferior (to attach to them) or to learn about thread
exit was to coordinate with the inferior's glibc/runtime, using
libthread_db.  That works by putting a breakpoint at a magic address
which is called when a new thread is spawned, or when a thread is
about to exit.  When that breakpoint is hit, all threads are stopped,
and then GDB coordinates with libthread_db to read data structures out
of the inferior to learn about what happened.  Then the breakpoint is
single-stepped, and then all threads are re-resumed.  This isn't very
efficient (stops all threads) and is more fragile (inferior's thread
list in memory may be corrupt; libthread_db bugs, etc.) than ideal.

When the kernel supports PTRACE_EVENT_CLONE (which we already make use
of), there's really no need to use libthread_db's event reporting
mechanism to learn about new LWPs.  And if the kernel supports that,
then we learn about LWP exits through regular WIFEXITED wait statuses,
so no need for the death event breakpoint either.

GDBserver has been likewise skipping the thread_db events for a long
while:
  https://sourceware.org/ml/gdb-patches/2007-10/msg00547.html

There's one user-visible difference: we'll no longer print about
threads being created and exiting while the program is running, like:

 [Thread 0x7ffff7dbb700 (LWP 30670) exited]
 [New Thread 0x7ffff7db3700 (LWP 30671)]
 [Thread 0x7ffff7dd3700 (LWP 30667) exited]
 [New Thread 0x7ffff7dab700 (LWP 30672)]
 [Thread 0x7ffff7db3700 (LWP 30671) exited]
 [Thread 0x7ffff7dcb700 (LWP 30668) exited]

This is exactly the same behavior as when debugging against remote
targets / gdbserver.  I actually think that's a good thing (and as
such have listed this in the local/remote parity wiki page a while
ago), as the printing slows down the inferior.  It's also a
distraction to keep bothering the user about short-lived threads that
she won't be able to interact with anyway.  Instead, the user (and
frontend) will be informed about new threads that currently exist in
the program when the program next stops:

 (gdb) c
 ...
 * ctrl-c *
 [New Thread 0x7ffff7963700 (LWP 7797)]
 [New Thread 0x7ffff796b700 (LWP 7796)]

 Program received signal SIGINT, Interrupt.
 [Switching to Thread 0x7ffff796b700 (LWP 7796)]
 clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:81
 81              testq   %rax,%rax
 (gdb) info threads

A couple of tests had assumptions on GDB thread numbers that no longer
hold.

Tested on x86_64 Fedora 20.

gdb/
2014-01-09  Pedro Alves  <palves@redhat.com>

	Skip enabling event reporting if the kernel supports
	PTRACE_EVENT_CLONE.
	* linux-thread-db.c: Include "nat/linux-ptrace.h".
	(thread_db_use_events): New function.
	(try_thread_db_load_1): Check thread_db_use_events before enabling
	event reporting.
	(update_thread_state): New function.
	(attach_thread): Use it.  Check thread_db_use_events before
	enabling event reporting.
	(thread_db_detach): Check thread_db_use_events before disabling
	event reporting.
	(find_new_threads_callback): Check thread_db_use_events before
	enabling event reporting.  Update the thread's state if not using
	libthread_db events.

gdb/testsuite/
2014-01-09  Pedro Alves  <palves@redhat.com>

	* gdb.threads/fork-thread-pending.exp: Switch to the main thread
	instead of to thread 2.
	* gdb.threads/signal-command-multiple-signals-pending.c (main):
	Add barrier around each pthread_create call instead of around all
	calls.
	* gdb.threads/signal-command-multiple-signals-pending.exp (test):
	Set a break on thread_function and have the child threads hit it
	one at at a time.
2015-01-09 11:42:57 +00:00
Pedro Alves
60b3033e6e skip "attach" tests when testing against stub-like targets
We already skip "attach" tests if the target board is remote, in
dejagnu's sense, as we use TCL's exec to spawn the program on the
build machine.  We should also skip these tests if testing with
"target remote" or other stub-like targets where "attach" doesn't make
sense.

Add a helper procedure that centralizes the checks a test that needs
to spawn a program for testing "attach" and make all test files that
use spawn_wait_for_attach check it.

gdb/testsuite/
2015-01-09  Pedro Alves  <palves@redhat.com>

	* lib/gdb.exp (can_spawn_for_attach): New procedure.
	(spawn_wait_for_attach): Error out if can_spawn_for_attach returns
	false.
	* gdb.base/attach.exp: Use can_spawn_for_attach instead of
	checking whether the target board is remote.
	* gdb.multi/multi-attach.exp: Likewise.
	* gdb.python/py-sync-interp.exp: Likewise.
	* gdb.server/ext-attach.exp: Likewise.
	* gdb.python/py-prompt.exp: Use can_spawn_for_attach before the
	tests that need to attach, instead of checking whether the target
	board is remote at the top of the file.
2015-01-09 11:04:19 +00:00
Yao Qi
acc018ac03 Recognize branch instruction on MIPS in gdb.trace/entry-values.exp
The test entry-values.exp doesn't recognize the call instructions
on MIPS, such as JAL, JALS and etc, so this patch sets call_insn
to match various jump and branch instructions first.

Currently, we assume the next instruction address of call instruction
is the address returned from foo, however it is not correct on MIPS
which has delay slot.  We extend variable call_insn to match one
instruction after jump or branch instruction, so that
$returned_from_foo is correct on MIPS.

All tests in entry-values.exp are PASS.

gdb/testsuite:

2015-01-08  Yao Qi  <yao@codesourcery.com>

	* gdb.trace/entry-values.exp: Set call_insn for MIPS target.
2015-01-08 11:45:51 +08:00
Jan Kratochvil
50a18af83d [testsuite patch] Fix avx512.exp regression
+gdb compile failed, ^[[01m^[[Kgdb/testsuite/gdb.arch/i386-avx512.c:20:27:^[[m^[[K ^[[01;31m^[[Kfatal error: ^[[m^[[Knat/x86-cpuid.h: No
such file or directory
+ #include "nat/x86-cpuid.h"
+^[[01;32m^[[K                           ^^[[m^[[K
+compilation terminated.
+UNTESTED: gdb.arch/i386-avx512.exp: i386-avx512.exp

125f8a3dde is the first bad commit
commit 125f8a3dde
Author: Gary Benson <gbenson@redhat.com>
Date:   Thu Jun 19 14:46:38 2014 +0100
    Move shared native target specific code to gdb/nat

gdb/testsuite/ChangeLog
2015-01-07  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Fix testcase compilation.
	* gdb.arch/i386-avx512.exp (comp_flags): Remove /common.
2015-01-07 15:42:57 +01:00
Joel Brobecker
8503d6e1e5 gdb/python: exception trying to create empty array
The following python command fails:

    (gdb) python print gdb.lookup_type('char').array(1, 0)
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
    ValueError: Array length must not be negative
    Error while executing Python code.

The above is trying to create an empty array, which is fairly command
in Ada.

gdb/ChangeLog:

        * python/py-type.c (typy_array_1): Do not raise negative-length
        exception if N2 is equal to N1 - 1.

gdb/testsuite/ChangeLog:

        * gdb.python/py-type.exp: Add a couple test about empty
        array creation, and negative-length array creation.
2015-01-06 19:07:12 +04:00
Doug Evans
e1e061e77d fix spelling of anon-ns2.cc in earlier entry, and whitespace in same entry 2015-01-03 12:35:41 -08:00
Doug Evans
cc73dbcc08 gdb.cp/nsalias.exp: Fix output of external/declaration flags.
gdb/testsuite/ChangeLog:

	* gdb.cp/nsalias.exp: Fix output of external/declaration flags.
2015-01-02 22:00:57 -08:00
Doug Evans
0300bbc7c5 gdb.dwarf2/dw4-sig-types.exp: Also pass -fdebug-types-section to gcc.
gdb/testsuite/ChangeLog:

	* gdb.dwarf2/dw4-sig-types.exp: Also pass -fdebug-types-section to gcc.
2015-01-02 12:59:44 -08:00
Joel Brobecker
32d0add0a6 Update year range in copyright notice of all files owned by the GDB project.
gdb/ChangeLog:

        Update year range in copyright notice of all files.
2015-01-01 13:32:14 +04:00
Yao Qi
9d85a0ec6b Clean up gdb.trace/entry-values.exp
This patch is to clean up gdb.trace/entry-values.exp as a preparation
of the next patch.  It updates the comments to reflect the code.

One DIE generated in dwarf assembler is

 		GNU_call_site {
		    {low_pc "$bar_start + $bar_call_foo" addr}
 		    {abstract_origin :$foo_label}

the DW_AT_low_pc attribute is the return address after the call, so I
rename variable bar_call_foo to returned_from_foo.

gdb/testsuite:

2014-12-29  Yao Qi  <yao@codesourcery.com>

	* gdb.trace/entry-values.exp: Update comments.  Rename variable
	bar_call_foo to returned_from_foo.
2014-12-29 15:42:38 +08:00
Mihail-Marian Nistor
87186c6a5c gdb/17394: cannot put breakpoint only in selected ASM file.
This patch fixes a problem when trying to insert a breakpoint on
a specific symbol defined in a specific file, eg:

    break foo.c:func

This currently works for files in C/C++/Ada, etc, but doesn't always
work for Asm files. Analysis of the problem showed that this related
to a limitation in gas, which does not generate debug info for functions/
symbols.  Thus, we have a symtab for the file ("info sources" shows
the file), but it contains no symbols.

When find_linespec_symbols is called in linespec_parse_basic, it calls
find_function_symbols, which uses add_matching_symbols_to_info to
collect all matching symbols.

That function does [pardon any mangled formatting]:

  for (ix = 0; VEC_iterate (symtab_ptr, info->file_symtabs, ix, elt); ++ix)
    {
      if (elt == NULL)
        {
          iterate_over_all_matching_symtabs (info->state, name, VAR_DOMAIN,
                                             collect_symbols, info,
                                             pspace, 1);
          search_minsyms_for_name (info, name, pspace);
        }
      else if (pspace == NULL || pspace == SYMTAB_PSPACE (elt))
        {
          /* Program spaces that are executing startup should have
             been filtered out earlier.  */
          gdb_assert (!SYMTAB_PSPACE (elt)->executing_startup);
          set_current_program_space (SYMTAB_PSPACE (elt));
          iterate_over_file_blocks (elt, name, VAR_DOMAIN,
                                    collect_symbols, info);
        }
    }

This iterates over the symtabs. In the failing use case, ELT is
non-NULL (points to the symtab for the .s file), so it calls
iterate_over_file_blocks. Herein is where the problem exists: it is
assumed that if NAME exists, it must exist in the given symtab -- a
reasonable assumption for "normal" (non-asm) cases. It never searches
minimal symbols (or in the global default symtab).

This patch fixes the problem by doing so. It is important to note that
iterating over minsyms is fairly expensive, so this patch only adds
that extra search if the language is language_asm and
iterate_over_file_blocks returns no symbols.

gdb/ChangeLog:
2014-12-20  Keith Seitz  <keiths@redhat.com>
            Mihail-Marian Nistor  <mihail.nistor@freescale.com>

        PR gdb/17394
        * linespec.c (struct collect_minsyms): Add new member `symtab'.
        (add_minsym): Handle cases where info.symtab is non-NULL.
        (search_minsyms_for_name): Add new parameter `symtab'.
        Handle limiting searches to a specific symtab.
        (add_matching_symtabs_to_info): Search through minimal symbols
        for language_asm files for which no new symbols are found.

gdb/testsuite/ChangeLog:
2014-12-20  Mihail-Marian Nistor  <mihail.nistor@freescale.com>

        PR gdb/17394
        * gdb.linespec/break-asm-file.c: New file.
        * gdb.linespec/break-asm-file.exp: New file.
        * gdb.linespec/break-asm-file0.s: New file.
        * gdb.linespec/break-asm-file1.s: New file.
2014-12-20 11:32:25 -05:00
Yao Qi
1bab73830f MIPS: Provide FPU info and decode FCSR in `info float'
This patch is the V2.  V1 can be found in
https://sourceware.org/ml/gdb-patches/2012-05/msg00938.html
V2 is to address Joel's comment
<https://sourceware.org/ml/gdb-patches/2012-06/msg00289.html> about
keeping dumping floating point registers.  Additionally, command
'info float' prints bits on nan2008 and abs2008.

------------------------------------------------------------------

 The change below provides a MIPS-specific handler for the:

(gdb) info float

command.  It provides information about the FPU type available (if any),
the FPU register width, and decodes the CP1 Floating Point Control and
Status Register (FCSR):

(gdb) print /x $fsr
$1 = 0xff83ffff
(gdb) info float
fpu type: double-precision
reg size: 32 bits
cond    : 0 1 2 3 4 5 6 7
cause   : inexact uflow oflow div0 inval unimp
mask    : inexact uflow oflow div0 inval
flags   : inexact uflow oflow div0 inval
rounding: -inf
flush   : zero

 One point to note about CP1.FCSR are the non-standard Flush-to-Nearest
and Flush-Override bits.  They are not a part of the MIPS architecture and
take two positions reserved for an implementation-dependent use in the
architecture.  They are present in all the FPU implementations made by
MIPS Technologies since the spin-off from SGI.

 I haven't been able to track down a single other MIPS FPU implementation
that would make any use of these bits and they are required to be
hardwired to zero by the architecture specification if unimplemented.
Therefore I think it makes sense to report them in the current way.

 GDB has no guaranteed access to the CP0 Processor Identification (PRId)
register to validate this feature properly and the ID information stored
in the CP1 Floating Point Implementation Register (FIR) is from my
experience not reliable enough (there's no Company ID available there for
once unlike in CP0.PRId and Processor ID is not guaranteed to be unique).

 As a side note we should probably dump CP1.FIR information as well, as
there's useful stuff indicating some FPU features there.  That's material
for another change however.

gdb/

2014-12-18  Nigel Stephens  <nigel@mips.com>
            Maciej W. Rozycki  <macro@codesourcery.com>

	* mips-tdep.c (print_fpu_flags): New function.
	(mips_print_float_info): Likewise.
	(mips_gdbarch_init): Install mips_print_float_info as gdbarch
	print_float_info routine.

gdb/testsuite/

2014-12-18  Nigel Stephens  <nigel@mips.com>
            Maciej W. Rozycki  <macro@codesourcery.com>

	* gdb.base/float.exp: Handle the new output from "info float" on
	MIPS targets.
2014-12-18 20:47:28 +08:00
Jan Kratochvil
1bc1068a0c Fix MinGW compilation
On Sun, 14 Dec 2014 07:00:28 +0100, Yao Qi wrote:
The build on mingw host is broken because mingw has no mkdtemp.

../../../git/gdb/compile/compile.c: In function 'get_compile_file_tempdir':
../../../git/gdb/compile/compile.c:194:3: error: implicit declaration of function 'mkdtemp' [-Werror=implicit-function-declaration]
   tempdir_name = mkdtemp (tname);
   ^
../../../git/gdb/compile/compile.c:194:16: error: assignment makes pointer from integer without a cast [-Werror]
   tempdir_name = mkdtemp (tname);
                ^
cc1: all warnings being treated as errors

In the end I have managed to test it by Wine myself:

$ wine build_win32/gdb/gdb.exe -q build_win32/gdb/gdb.exe -ex start -ex 'compile code 1' -ex 'set confirm no' -ex quit
[...]
Temporary breakpoint 1, main (argc=1, argv=0x241418) at ../../gdb/gdb.c:29
29        args.argc = argc;
Could not load libcc1.so: Module not found.

Even if it managed to load libcc1.so (it needs host-dependent name libcc1.dll)
then it would soon end up at least on:

default_infcall_mmap:
  error (_("This target does not support inferior memory allocation by mmap."));

As currently there is only:

linux-tdep.c:
  set_gdbarch_infcall_mmap (gdbarch, linux_infcall_mmap);

While one could debug Linux targets from MS-Windows host I find it somehow
overcomplicated now when we are trying to get it running at least on native
Linux x86*.

The 'compile' project needs a larger port effort to run on MS-Windows.

gdb/ChangeLog
2014-12-17  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Fix MinGW compilation.
	* compile/compile.c (get_compile_file_tempdir): Call error if
	!HAVE_MKDTEMP.
	* config.in: Regenerate.
	* configure: Regenerate.
	* configure.ac (AC_CHECK_FUNCS): Add mkdtemp.

gdb/testsuite/ChangeLog
2014-12-17  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Fix MinGW compilation.
	* gdb.compile/compile-ops.exp: Update untested message if
	!skip_compile_feature_tests.
	* gdb.compile/compile-setjmp.exp: Likewise.
	* gdb.compile/compile-tls.exp: Likewise.
	* gdb.compile/compile.exp: Likewise.
	* lib/gdb.exp (skip_compile_feature_tests): Check also "Command not
	supported on this host".
2014-12-17 20:09:02 +01:00
Doug Evans
b6615d1086 boards/stabs.exp: New file.
gdb/ChangeLog:

	* boards/stabs.exp: New file.
2014-12-16 23:10:54 -08:00
Andreas Arnez
25dda427ec Fix indentation of "maint print user-registers"
This fixes a failure of the test case "complete 'info registers '" in
completion.exp on architectures where the user registers have numbers
above 99.  In that case the output of "maint print user-registers" was
no longer indented, and the regexp in the test case failed to add them
to the list of expected completion results.  The fix also swaps the
columns "Name" and "Nr", such that the indentation is always the same,
and to be consistent with the output of "maint print registers".

gdb/ChangeLog:

	* user-regs.c (maintenance_print_user_registers): Swap "Nr" and
	"Name" columns.  Assure that the output is always indented.

gdb/testsuite/ChangeLog:

	* gdb.base/completion.exp: Adjust to format changes of "maint
	print user-registers".
2014-12-16 16:06:42 +01:00
Catalin Udma
bf330350c2 aarch64/gdbserver: fix floating point registers display
When using aarch64 gdb with gdbserver, floating point registers are
not correctly displayed, as below:
  (gdb) info registers fpsr fpcr
  fpsr           <unavailable>
  fpcr           <unavailable>

To fix these problems, the missing fpsr and fpcr registers are added
when floating point registers are read/write
Add test for aarch64 floating point
PR server/17457

gdb/gdbserver/

    PR server/17457
    * linux-aarch64-low.c (AARCH64_FPSR_REGNO): New define.
    (AARCH64_FPCR_REGNO): Likewise.
    (AARCH64_NUM_REGS): Update to include fpsr/fpcr registers.
    (aarch64_fill_fpregset): Add missing fpsr/fpcr registers.
    (aarch64_store_fpregset): Likewise.

gdb/testsuite/

    PR server/17457
    * gdb.arch/aarch64-fp.c: New file.
    * gdb.arch/aarch64-fp.exp: New file.

Signed-off-by: Catalin Udma <catalin.udma@freescale.com>
2014-12-16 09:51:42 +02:00
Sergio Durigan Junior
395cf596db Merge dg-extract-results.{sh,py} from GCC upstream
It has been a while since we don't sync this file with GCC upstream,
and in the meantime some interesting things have happened.  The most
interesting is the inclusion of a new dg-extract-results.py which is
apparently faster than its shell equivalent.

This merge will probably fix the bug described in

  <https://sourceware.org/ml/gdb-patches/2014-12/msg00421.html>

Though I am still proposing the patch for upstream GCC.  Once it gets
accepted, I will merge it too.

OK to apply?

gdb/testsuite/ChangeLog:
2014-12-15  Sergio Durigan Junior  <sergiodj@redhat.com>

	Merge dg-extract-results.{sh,py} from GCC upstream (r210243,
	r210637, r210913, r211666, r215400, r215817).

	2014-05-08  Richard Sandiford  <rdsandiford@googlemail.com>
		* dg-extract-results.py: New file.
		* dg-extract-results.sh: Use it if the environment seems
		suitable.

	2014-05-20  Richard Sandiford  <rdsandiford@googlemail.com>

		* dg-extract-results.py (parse_run): Handle warnings that
		are printed before a test harness is run.

	2014-05-25  Richard Sandiford  <rdsandiford@googlemail.com>

		* dg-extract-results.py (Named): Remove __cmp__ method.
		(output_variation): Use a key to sort variation.harnesses.

	2014-06-14  Richard Sandiford  <rdsandiford@googlemail.com>

		* dg-extract-results.py: For Python 3, force sys.stdout to
		handle surrogate escape sequences.
		(safe_open): New function.
		(output_segment, main): Use it.

	2014-09-19  Segher Boessenkool  <segher@kernel.crashing.org>

		* dg-extract-results.py (Prog.result_re): Include options
		in test name.

	2014-10-02  Segher Boessenkool  <segher@kernel.crashing.org>

		* dg-extract-results.py (output_variation): Always sort if
		do_sum.
2014-12-15 19:37:55 -05:00
Simon Marchi
e882ef3cfc testsuite: expect possible pagination when starting gdb
When gdb starts, the lines that appear before the first prompt may get
paginated if the terminal in which the tests are ran is too small (in
terms of rows). These lines include the welcome/license message and
possibly more, such as "Reading symbols from...". Pagination is disabled
right after gdb is started (with "set height 0"), but this output happens
before we are able to set height.

If these lines get paginated, gdb waits for the user to press enter and
the test harness waits for gdb to print its prompt, resulting in a
deadlock.

My first idea was to launch gdb with --quiet. However, some lines are
still printed ("Reading symbols from...", some more stuff when attaching
with --pid, etc).

The proposed solution simply expects that pagination can occur after
starting gdb. If this is the case, it sends a "\n" and loops.

gdb/testsuite/Changelog:

	* lib/gdb.exp (default_gdb_start): After starting gdb, loop
	as long as we get pagination notifications.
2014-12-15 11:46:44 -05:00
Jason Merrill
4992aa2019 * Makefile.in (check-gdb.%): Restore.
* README: Mention it.
2014-12-15 10:35:30 -05:00
Joel Brobecker
c1b5a1a6e7 Internal error trying to print uninitialized string.
Trying to print the value of a string whose size is not known at
compile-time before it gets assigned a value can lead to the following
internal error:

    (gdb) p my_str
    $1 =
    /[...]/utils.c:1089: internal-error: virtual memory exhausted.

What happens is that my_str is described as a reference to an array
type whose bounds are dynamic. During the read of that variable's
value (in default_read_var_value), we end up resolving dynamic types
which, for reference types, makes us also resolve the target of that
reference type. This means we resolve our variable to a reference
to an array whose bounds are undefined, and unfortunately very far
appart.

So, when we pass that value to ada-valprint, and in particular to
da_val_print_ref, we eventually try to allocate too large of a buffer
corresponding to the (bogus) size of our array, hence the internal
error.

This patch fixes the problem by adding a size_check before trying
to print the dereferenced value. To perform this check, a function
that was previously specific to ada-lang.c (check_size) gets
exported, and renamed to something less prone to name collisions
(ada_ensure_varsize_limit).

gdb/ChangeLog:

        * ada-lang.h (ada_ensure_varsize_limit): Declare.
        * ada-lang.c (check_size): Remove advance declaration.
        (ada_ensure_varsize_limit): Renames check_size.
        Replace calls to check_size by calls to ada_ensure_varsize_limit
        throughout.
        * ada-valprint.c (ada_val_print_ref): Add call to
        ada_ensure_varsize_limit.  Add comment explaining why.

gdb/testsuite/ChangeLog:

        * gdb.ada/str_uninit: New testcase.
2014-12-13 11:00:24 -05:00
Jan Kratochvil
5537b57769 Fix 7.8 regression: resolve_dynamic_struct: Assertion `TYPE_NFIELDS (type) > 0' (PR 17642)
https://sourceware.org/bugzilla/show_bug.cgi?id=17642

Regression since:
commit 012370f681
Author: Tom Tromey <tromey@redhat.com>
Date:   Thu May 8 11:26:44 2014 -0600
    handle VLA in a struct or union

Bugreport:
Regression with gdb scripts for Linux kernel
https://sourceware.org/ml/gdb/2014-08/msg00127.html

That big change after "else" is just reindentation.

gdb/ChangeLog
2014-12-13  Jan Kratochvil  <jan.kratochvil@redhat.com>

	PR symtab/17642
	* gdbtypes.c (resolve_dynamic_type_internal): Apply check_typedef to
	TYPE if not TYPE_CODE_TYPEDEF.

gdb/testsuite/ChangeLog
2014-12-13  Jan Kratochvil  <jan.kratochvil@redhat.com>

	PR symtab/17642
	* gdb.base/vla-stub-define.c: New file.
	* gdb.base/vla-stub.c: New file.
	* gdb.base/vla-stub.exp: New file.
2014-12-13 15:31:59 +01:00
Tom Tromey
bb2ec1b34e the "compile" command
This final patch adds the new "compile" command and subcommands, and
all the machinery needed to make it work.

A shared library supplied by gcc is used for all communications with
gcc.  Types and most aspects of symbols are provided directly by gdb
to the compiler using this library.

gdb provides some information about the user's code using plain text.
Macros are emitted this way, and DWARF location expressions (and
bounds for VLA) are compiled to C code.

This hybrid approach was taken because, on the one hand, it is better
to provide global declarations and such on demand; but on the other
hand, for local variables, translating DWARF location expressions to C
was much simpler than exporting a full compiler API to gdb -- the same
result, only easier to implement, understand, and debug.

In the ordinary mode, the user's expression is wrapped in a dummy
function.  After compilation, gdb inserts the resulting object code
into the inferior, then calls this function.

Access to local variables is provided by noting which registers are
used by location expressions, and passing a structure of register
values into the function.  Writes to registers are supported by
copying out these values after the function returns.

This approach was taken so that we could eventually implement other
more interesting features based on this same infrastructure; for
example, we're planning to investigate inferior-side breakpoint
conditions.

gdb/ChangeLog
2014-12-12  Phil Muldoon  <pmuldoon@redhat.com>
	    Jan Kratochvil  <jan.kratochvil@redhat.com>
	    Tom Tromey  <tromey@redhat.com>

	* NEWS: Update.
	* symtab.h (struct symbol_computed_ops) <generate_c_location>: New
	field.
	* p-lang.c (pascal_language_defn): Update.
	* opencl-lang.c (opencl_language_defn): Update.
	* objc-lang.c (objc_language_defn): Update.
	* m2-lang.c (m2_language_defn): Update.
	* language.h (struct language_defn) <la_get_compile_instance,
	la_compute_program>: New fields.
	* language.c (unknown_language_defn, auto_language_defn)
	(local_language_defn): Update.
	* jv-lang.c (java_language_defn): Update.
	* go-lang.c (go_language_defn): Update.
	* f-lang.c (f_language_defn): Update.
	* dwarf2loc.h (dwarf2_compile_property_to_c): Declare.
	* dwarf2loc.c (dwarf2_compile_property_to_c)
	(locexpr_generate_c_location, loclist_generate_c_location): New
	functions.
	(dwarf2_locexpr_funcs, dwarf2_loclist_funcs): Update.
	* defs.h (enum compile_i_scope_types): New.
	(enum command_control_type) <compile_control>: New constant.
	(struct command_line) <control_u>: New field.
	* d-lang.c (d_language_defn): Update.
	* compile/compile.c: New file.
	* compile/compile-c-support.c: New file.
	* compile/compile-c-symbols.c: New file.
	* compile/compile-c-types.c: New file.
	* compile/compile.h: New file.
	* compile/compile-internal.h: New file.
	* compile/compile-loc2c.c: New file.
	* compile/compile-object-load.c: New file.
	* compile/compile-object-load.h: New file.
	* compile/compile-object-run.c: New file.
	* compile/compile-object-run.h: New file.
	* cli/cli-script.c (multi_line_command_p, print_command_lines)
	(execute_control_command, process_next_line)
	(recurse_read_control_structure): Handle compile_control.
	* c-lang.h (c_get_compile_context, c_compute_program): Declare.
	* c-lang.c (c_language_defn, cplus_language_defn)
	(asm_language_defn, minimal_language_defn): Update.
	* ada-lang.c (ada_language_defn): Update.
	* Makefile.in (SUBDIR_GCC_COMPILE_OBS, SUBDIR_GCC_COMPILE_SRCS):
	New variables.
	(SFILES): Add SUBDIR_GCC_COMPILE_SRCS.
	(HFILES_NO_SRCDIR): Add compile.h.
	(COMMON_OBS): Add SUBDIR_GCC_COMPILE_OBS.
	(INIT_FILES): Add SUBDIR_GCC_COMPILE_SRCS.
	(compile.o, compile-c-types.o, compile-c-symbols.o)
	(compile-object-load.o, compile-object-run.o, compile-loc2c.o)
	(compile-c-support.o): New targets.

gdb/doc/ChangeLog
2014-12-12  Phil Muldoon  <pmuldoon@redhat.com>
	    Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.texinfo (Altering): Update.
	(Compiling and Injecting Code): New node.

gdb/testsuite/ChangeLog
2014-12-12  Phil Muldoon  <pmuldoon@redhat.com>
	    Jan Kratochvil  <jan.kratochvil@redhat.com>
	    Tom Tromey  <tromey@redhat.com>

	* configure.ac: Add gdb.compile/.
	* configure: Regenerate.
	* gdb.compile/Makefile.in: New file.
	* gdb.compile/compile-ops.exp: New file.
	* gdb.compile/compile-ops.c: New file.
	* gdb.compile/compile-tls.c: New file.
	* gdb.compile/compile-tls.exp: New file.
	* gdb.compile/compile-constvar.S: New file.
	* gdb.compile/compile-constvar.c: New file.
	* gdb.compile/compile-mod.c: New file.
	* gdb.compile/compile-nodebug.c: New file.
	* gdb.compile/compile-setjmp-mod.c: New file.
	* gdb.compile/compile-setjmp.c: New file.
	* gdb.compile/compile-setjmp.exp: New file.
	* gdb.compile/compile-shlib.c: New file.
	* gdb.compile/compile.c: New file.
	* gdb.compile/compile.exp: New file.
	* lib/gdb.exp (skip_compile_feature_tests): New proc.
2014-12-12 22:28:44 +01:00
Tom Tromey
4ff709eb44 add some missing ops to DWARF assembler
This changes the DWARF assembler to allow comments in a location
expression, and also adds support for a few new opcodes I needed.

gdb/testsuite/ChangeLog
2014-12-12  Tom Tromey  <tromey@redhat.com>

	* lib/dwarf.exp (_location): Ignore blank lines.  Allow comments.
	Handle DW_OP_pick, DW_OP_skip, DW_OP_bra.
2014-12-12 22:24:17 +01:00
Doug Evans
6dddd6a574 New python function gdb.lookup_objfile.
gdb/ChangeLog:

	* NEWS: Mention gdb.lookup_objfile.
	* python/python.c (GdbMethods): Add lookup_objfile.
	* python/python-internal.h (gdbpy_lookup_objfile): Declare.
	* python/py-objfile.c: #include "symtab.h".
	(objfpy_build_id_ok, objfpy_build_id_matches): New functions.
	(objfpy_lookup_objfile_by_name): New function.
	(objfpy_lookup_objfile_by_build_id): New function.
	(gdbpy_lookup_objfile): New function.

gdb/doc/ChangeLog:

	* python.texi (Objfiles In Python): Document gdb.lookup_objfile.

gdb/testsuite/ChangeLog:

	* lib/gdb-python.exp (get_python_valueof): New function.
	* gdb.python/py-objfile.exp: Add tests for gdb.lookup_objfile.
2014-12-12 09:48:13 -08:00
Andreas Arnez
71c247087c Provide completer for "info registers"
Provide a new completion function for the argument of "info
registers", "info all-registers", and the "lr" command in dbx mode.
Without this patch the default symbol completer is used, which is more
confusing than helpful.

Also add a test for this new feature to "completion.exp": Determine
the target's available set of registers/reggroups and compare this to
the completion of "info registers ".  For determining the available
registers involve the new "maint print user-registers" command.

gdb/ChangeLog:

	* completer.c: Include "target.h", "reggroups.h", and
	"user-regs.h".
	(reg_or_group_completer): New.
	* completer.h (reg_or_group_completer): Declare.
	* infcmd.c (_initialize_infcmd): Set reg_or_group_completer for
	the "info registers" and "info all-registers" commands and the
	dbx-mode "lr" command.

gdb/testsuite/ChangeLog:

	* gdb.base/completion.exp: Add test for completion of "info
	registers ".
2014-12-12 17:11:22 +01:00
Maciej W. Rozycki
3e29f34a4e MIPS: Keep the ISA bit in compressed code addresses
1. Background information

The MIPS architecture, as originally designed and implemented in
mid-1980s has a uniform instruction word size that is 4 bytes, naturally
aligned.  As such all MIPS instructions are located at addresses that
have their bits #1 and #0 set to zeroes, and any attempt to execute an
instruction from an address that has any of the two bits set to one
causes an address error exception.  This may for example happen when a
jump-register instruction is executed whose register value used as the
jump target has any of these bits set.

Then in mid 1990s LSI sought a way to improve code density for their
TinyRISC family of MIPS cores and invented an alternatively encoded
instruction set in a joint effort with MIPS Technologies (then a
subsidiary of SGI).  The new instruction set has been named the MIPS16
ASE (Application-Specific Extension) and uses a variable instruction
word size, which is 2 bytes (as the name of the ASE suggests) for most,
but there are a couple of exceptions that take 4 bytes, and then most of
the 2-byte instructions can be treated with a 2-byte extension prefix to
expand the range of the immediate operands used.

As a result instructions are no longer 4-byte aligned, instead they are
aligned to a multiple of 2.  That left the bit #0 still unused for code
references, be it for the standard MIPS (i.e. as originally invented) or
for the MIPS16 instruction set, and based on that observation a clever
trick was invented that on one hand allowed the processor to be
seamlessly switched between the two instruction sets at any time at the
run time while on the other avoided the introduction of any special
control register to do that.

So it is the bit #0 of the instruction address that was chosen as the
selector and named the ISA bit.  Any instruction executed at an even
address is interpreted as a standard MIPS instruction (the address still
has to have its bit #1 clear), any instruction executed at an odd
address is interpreted as a MIPS16 instruction.

To switch between modes ordinary jump instructions are used, such as
used for function calls and returns, specifically the bit #0 of the
source register used in jump-register instructions selects the execution
(ISA) mode for the following piece of code to be interpreted in.
Additionally new jump-immediate instructions were added that flipped the
ISA bit to select the opposite mode upon execution.  They were
considered necessary to avoid the need to make register jumps in all
cases as the original jump-immediate instructions provided no way to
change the bit #0 at all.

This was all important for cases where standard MIPS and MIPS16 code had
to be mixed, either for compatibility with the existing binary code base
or to access resources not reachable from MIPS16 code (the MIPS16
instruction set only provides access to general-purpose registers, and
not for example floating-point unit registers or privileged coprocessor
0 registers) -- pieces of code in the opposite mode can be executed as
ordinary subroutine calls.

A similar approach has been more recently adopted for the MIPS16
replacement instruction set defined as the so called microMIPS ASE.
This is another instruction set encoding introduced to the MIPS
architecture.  Just like the MIPS16 ASE, the microMIPS instruction set
uses a variable-length encoding, where each instruction takes a multiple
of 2 bytes.  The ISA bit has been reused and for microMIPS-capable
processors selects between the standard MIPS and the microMIPS mode
instead.

2. Statement of the problem

To put it shortly, MIPS16 and microMIPS code pointers used by GDB are
different to these observed at the run time.  This results in the same
expressions being evaluated producing different results in GDB and in
the program being debugged.  Obviously it's the results obtained at the
run time that are correct (they define how the program behaves) and
therefore by definition the results obtained in GDB are incorrect.

A bit longer description will record that obviously at the run time the
ISA bit has to be set correctly (refer to background information above
if unsure why so) or the program will not run as expected.  This is
recorded in all the executable file structures used at the run time: the
dynamic symbol table (but not always the static one!), the GOT, and
obviously in all the addresses embedded in code or data of the program
itself, calculated by applying the appropriate relocations at the static
link time.

While a program is being processed by GDB, the ISA bit is stripped off
from any code addresses, presumably to make them the same as the
respective raw memory byte address used by the processor to access the
instruction in the instruction fetch access cycle.  This stripping is
actually performed outside GDB proper, in BFD, specifically
_bfd_mips_elf_symbol_processing (elfxx-mips.c, see the piece of code at
the very bottom of that function, starting with an: "If this is an
odd-valued function symbol, assume it's a MIPS16 or microMIPS one."
comment).

This function is also responsible for symbol table dumps made by
`objdump' too, so you'll never see the ISA bit reported there by that
tool, you need to use `readelf'.

This is however unlike what is ever done at the run time, the ISA bit
once present is never stripped off, for example a cast like this:

(short *) main

will not strip the ISA bit off and if the resulting pointer is intended
to be used to access instructions as data, for example for software
instruction decoding (like for fault recovery or emulation in a signal
handler) or for self-modifying code then the bit still has to be
stripped off by an explicit AND operation.

This is probably best illustrated with a simple real program example.
Let's consider the following simple program:

$ cat foobar.c
int __attribute__ ((mips16)) foo (void)
{
  return 1;
}

int __attribute__ ((mips16)) bar (void)
{
  return 2;
}

int __attribute__ ((nomips16)) foo32 (void)
{
  return 3;
}

int (*foo32p) (void) = foo32;
int (*foop) (void) = foo;
int fooi = (int) foo;

int
main (void)
{
  return foop ();
}
$

This is plain C with no odd tricks, except from the instruction mode
attributes.  They are not necessary to trigger this problem, I just put
them here so that the program can be contained in a single source file
and to make it obvious which function is MIPS16 code and which is not.

Let's try it with Linux, so that everyone can repeat this experiment:

$ mips-linux-gnu-gcc -mips16 -g -O2 -o foobar foobar.c
$

Let's have a look at some interesting symbols:

$ mips-linux-gnu-readelf -s foobar | egrep 'table|foo|bar'
Symbol table '.dynsym' contains 7 entries:
Symbol table '.symtab' contains 95 entries:
    55: 00000000     0 FILE    LOCAL  DEFAULT  ABS foobar.c
    66: 0040068c     4 FUNC    GLOBAL DEFAULT [MIPS16]    12 bar
    68: 00410848     4 OBJECT  GLOBAL DEFAULT   21 foo32p
    70: 00410844     4 OBJECT  GLOBAL DEFAULT   21 foop
    78: 00400684     8 FUNC    GLOBAL DEFAULT   12 foo32
    80: 00400680     4 FUNC    GLOBAL DEFAULT [MIPS16]    12 foo
    88: 00410840     4 OBJECT  GLOBAL DEFAULT   21 fooi
$

Hmm, no sight of the ISA bit, but notice how foo and bar (but not
foo32!) have been marked as MIPS16 functions (ELF symbol structure's
`st_other' field is used for that).

So let's try to run and poke at this program with GDB.  I'll be using a
native system for simplicity (I'll be using ellipses here and there to
remove unrelated clutter):

$ ./foobar
$ echo $?
1
$

So far, so good.

$ gdb ./foobar
[...]
(gdb) break main
Breakpoint 1 at 0x400490: file foobar.c, line 23.
(gdb) run
Starting program: .../foobar

Breakpoint 1, main () at foobar.c:23
23        return foop ();
(gdb)

Yay, it worked!  OK, so let's poke at it:

(gdb) print main
$1 = {int (void)} 0x400490 <main>
(gdb) print foo32
$2 = {int (void)} 0x400684 <foo32>
(gdb) print foo32p
$3 = (int (*)(void)) 0x400684 <foo32>
(gdb) print bar
$4 = {int (void)} 0x40068c <bar>
(gdb) print foo
$5 = {int (void)} 0x400680 <foo>
(gdb) print foop
$6 = (int (*)(void)) 0x400681 <foo>
(gdb)

A-ha!  Here's the difference and finally the ISA bit!

(gdb) print /x fooi
$7 = 0x400681
(gdb) p/x $pc
p/x $pc
$8 = 0x400491
(gdb)

And here as well...

(gdb) advance foo
foo () at foobar.c:4
4       }
(gdb) disassemble
Dump of assembler code for function foo:
   0x00400680 <+0>:     jr      ra
   0x00400682 <+2>:     li      v0,1
End of assembler dump.
(gdb) finish
Run till exit from #0  foo () at foobar.c:4
main () at foobar.c:24
24      }
Value returned is $9 = 1
(gdb) continue
Continuing.
[Inferior 1 (process 14103) exited with code 01]
(gdb)

So let's be a bit inquisitive...

(gdb) run
Starting program: .../foobar

Breakpoint 1, main () at foobar.c:23
23        return foop ();
(gdb)

Actually we do not like to run foo here at all.  Let's run bar instead!

(gdb) set foop = bar
(gdb) print foop
$10 = (int (*)(void)) 0x40068c <bar>
(gdb)

Hmm, no ISA bit.  Is it going to work?

(gdb) advance bar
bar () at foobar.c:9
9       }
(gdb) p/x $pc
$11 = 0x40068c
(gdb) disassemble
Dump of assembler code for function bar:
=> 0x0040068c <+0>:     jr      ra
   0x0040068e <+2>:     li      v0,2
End of assembler dump.
(gdb) finish
Run till exit from #0  bar () at foobar.c:9

Program received signal SIGILL, Illegal instruction.
bar () at foobar.c:9
9       }
(gdb)

Oops!

(gdb) p/x $pc
$12 = 0x40068c
(gdb)

We're still there!

(gdb) continue
Continuing.

Program terminated with signal SIGILL, Illegal instruction.
The program no longer exists.
(gdb)

So let's try something else:

(gdb) run
Starting program: .../foobar

Breakpoint 1, main () at foobar.c:23
23        return foop ();
(gdb) set foop = foo
(gdb) advance foo
foo () at foobar.c:4
4       }
(gdb) disassemble
Dump of assembler code for function foo:
=> 0x00400680 <+0>:     jr      ra
   0x00400682 <+2>:     li      v0,1
End of assembler dump.
(gdb) finish
Run till exit from #0  foo () at foobar.c:4

Program received signal SIGILL, Illegal instruction.
foo () at foobar.c:4
4       }
(gdb) continue
Continuing.

Program terminated with signal SIGILL, Illegal instruction.
The program no longer exists.
(gdb)

The same problem!

(gdb) run
Starting program:
/net/build2-lucid-cs/scratch/macro/mips-linux-fsf-gcc/isa-bit/foobar

Breakpoint 1, main () at foobar.c:23
23        return foop ();
(gdb) set foop = foo32
(gdb) advance foo32
foo32 () at foobar.c:14
14      }
(gdb) disassemble
Dump of assembler code for function foo32:
=> 0x00400684 <+0>:     jr      ra
   0x00400688 <+4>:     li      v0,3
End of assembler dump.
(gdb) finish
Run till exit from #0  foo32 () at foobar.c:14
main () at foobar.c:24
24      }
Value returned is $14 = 3
(gdb) continue
Continuing.
[Inferior 1 (process 14113) exited with code 03]
(gdb)

That did work though, so it's the ISA bit only!

(gdb) quit

Enough!

That's the tip of the iceberg only though.  So let's rebuild the
executable with some dynamic symbols:

$ mips-linux-gnu-gcc -mips16 -Wl,--export-dynamic -g -O2 -o foobar-dyn foobar.c
$ mips-linux-gnu-readelf -s foobar-dyn | egrep 'table|foo|bar'
Symbol table '.dynsym' contains 32 entries:
     6: 004009cd     4 FUNC    GLOBAL DEFAULT   12 bar
     8: 00410b88     4 OBJECT  GLOBAL DEFAULT   21 foo32p
     9: 00410b84     4 OBJECT  GLOBAL DEFAULT   21 foop
    15: 004009c4     8 FUNC    GLOBAL DEFAULT   12 foo32
    17: 004009c1     4 FUNC    GLOBAL DEFAULT   12 foo
    25: 00410b80     4 OBJECT  GLOBAL DEFAULT   21 fooi
Symbol table '.symtab' contains 95 entries:
    55: 00000000     0 FILE    LOCAL  DEFAULT  ABS foobar.c
    69: 004009cd     4 FUNC    GLOBAL DEFAULT   12 bar
    71: 00410b88     4 OBJECT  GLOBAL DEFAULT   21 foo32p
    72: 00410b84     4 OBJECT  GLOBAL DEFAULT   21 foop
    79: 004009c4     8 FUNC    GLOBAL DEFAULT   12 foo32
    81: 004009c1     4 FUNC    GLOBAL DEFAULT   12 foo
    89: 00410b80     4 OBJECT  GLOBAL DEFAULT   21 fooi
$

OK, now the ISA bit is there for a change, but the MIPS16 `st_other'
attribute gone, hmm...  What does `objdump' do then:

$ mips-linux-gnu-objdump -Tt foobar-dyn | egrep 'SYMBOL|foo|bar'
foobar-dyn:     file format elf32-tradbigmips
SYMBOL TABLE:
00000000 l    df *ABS*  00000000              foobar.c
004009cc g     F .text  00000004              0xf0 bar
00410b88 g     O .data  00000004              foo32p
00410b84 g     O .data  00000004              foop
004009c4 g     F .text  00000008              foo32
004009c0 g     F .text  00000004              0xf0 foo
00410b80 g     O .data  00000004              fooi
DYNAMIC SYMBOL TABLE:
004009cc g    DF .text  00000004  Base        0xf0 bar
00410b88 g    DO .data  00000004  Base        foo32p
00410b84 g    DO .data  00000004  Base        foop
004009c4 g    DF .text  00000008  Base        foo32
004009c0 g    DF .text  00000004  Base        0xf0 foo
00410b80 g    DO .data  00000004  Base        fooi
$

Hmm, the attribute (0xf0, printed raw) is back, and the ISA bit gone
again.

Let's have a look at some DWARF-2 records GDB uses (I'll be stripping
off a lot here for brevity) -- debug info:

$ mips-linux-gnu-readelf -wi foobar
Contents of the .debug_info section:
[...]
  Compilation Unit @ offset 0x88:
   Length:        0xbb (32-bit)
   Version:       4
   Abbrev Offset: 62
   Pointer Size:  4
 <0><93>: Abbrev Number: 1 (DW_TAG_compile_unit)
    <94>   DW_AT_producer    : (indirect string, offset: 0x19e): GNU C 4.8.0 20120513 (experimental) -meb -mips16 -march=mips32r2 -mhard-float -mllsc -mplt -mno-synci -mno-shared -mabi=32 -g -O2
    <98>   DW_AT_language    : 1        (ANSI C)
    <99>   DW_AT_name        : (indirect string, offset: 0x190): foobar.c
    <9d>   DW_AT_comp_dir    : (indirect string, offset: 0x225): [...]
    <a1>   DW_AT_ranges      : 0x0
    <a5>   DW_AT_low_pc      : 0x0
    <a9>   DW_AT_stmt_list   : 0x27
 <1><ad>: Abbrev Number: 2 (DW_TAG_subprogram)
    <ae>   DW_AT_external    : 1
    <ae>   DW_AT_name        : foo
    <b2>   DW_AT_decl_file   : 1
    <b3>   DW_AT_decl_line   : 1
    <b4>   DW_AT_prototyped  : 1
    <b4>   DW_AT_type        : <0xc2>
    <b8>   DW_AT_low_pc      : 0x400680
    <bc>   DW_AT_high_pc     : 0x400684
    <c0>   DW_AT_frame_base  : 1 byte block: 9c         (DW_OP_call_frame_cfa)
    <c2>   DW_AT_GNU_all_call_sites: 1
 <1><c2>: Abbrev Number: 3 (DW_TAG_base_type)
    <c3>   DW_AT_byte_size   : 4
    <c4>   DW_AT_encoding    : 5        (signed)
    <c5>   DW_AT_name        : int
 <1><c9>: Abbrev Number: 4 (DW_TAG_subprogram)
    <ca>   DW_AT_external    : 1
    <ca>   DW_AT_name        : (indirect string, offset: 0x18a): foo32
    <ce>   DW_AT_decl_file   : 1
    <cf>   DW_AT_decl_line   : 11
    <d0>   DW_AT_prototyped  : 1
    <d0>   DW_AT_type        : <0xc2>
    <d4>   DW_AT_low_pc      : 0x400684
    <d8>   DW_AT_high_pc     : 0x40068c
    <dc>   DW_AT_frame_base  : 1 byte block: 9c         (DW_OP_call_frame_cfa)
    <de>   DW_AT_GNU_all_call_sites: 1
 <1><de>: Abbrev Number: 2 (DW_TAG_subprogram)
    <df>   DW_AT_external    : 1
    <df>   DW_AT_name        : bar
    <e3>   DW_AT_decl_file   : 1
    <e4>   DW_AT_decl_line   : 6
    <e5>   DW_AT_prototyped  : 1
    <e5>   DW_AT_type        : <0xc2>
    <e9>   DW_AT_low_pc      : 0x40068c
    <ed>   DW_AT_high_pc     : 0x400690
    <f1>   DW_AT_frame_base  : 1 byte block: 9c         (DW_OP_call_frame_cfa)
    <f3>   DW_AT_GNU_all_call_sites: 1
 <1><f3>: Abbrev Number: 5 (DW_TAG_subprogram)
    <f4>   DW_AT_external    : 1
    <f4>   DW_AT_name        : (indirect string, offset: 0x199): main
    <f8>   DW_AT_decl_file   : 1
    <f9>   DW_AT_decl_line   : 21
    <fa>   DW_AT_prototyped  : 1
    <fa>   DW_AT_type        : <0xc2>
    <fe>   DW_AT_low_pc      : 0x400490
    <102>   DW_AT_high_pc     : 0x4004a4
    <106>   DW_AT_frame_base  : 1 byte block: 9c        (DW_OP_call_frame_cfa)
    <108>   DW_AT_GNU_all_tail_call_sites: 1
[...]
$

-- no sign of the ISA bit anywhere -- frame info:

$ mips-linux-gnu-readelf -wf foobar
[...]
Contents of the .debug_frame section:

00000000 0000000c ffffffff CIE
  Version:               1
  Augmentation:          ""
  Code alignment factor: 1
  Data alignment factor: -4
  Return address column: 31

  DW_CFA_def_cfa_register: r29
  DW_CFA_nop

00000010 0000000c 00000000 FDE cie=00000000 pc=00400680..00400684

00000020 0000000c 00000000 FDE cie=00000000 pc=00400684..0040068c

00000030 0000000c 00000000 FDE cie=00000000 pc=0040068c..00400690

00000040 00000018 00000000 FDE cie=00000000 pc=00400490..004004a4
  DW_CFA_advance_loc: 6 to 00400496
  DW_CFA_def_cfa_offset: 32
  DW_CFA_offset: r31 at cfa-4
  DW_CFA_advance_loc: 6 to 0040049c
  DW_CFA_restore: r31
  DW_CFA_def_cfa_offset: 0
  DW_CFA_nop
  DW_CFA_nop
  DW_CFA_nop
[...]
$

-- no sign of the ISA bit anywhere -- range info (GDB doesn't use arange):

$ mips-linux-gnu-readelf -wR foobar
Contents of the .debug_ranges section:

    Offset   Begin    End
    00000000 00400680 00400690
    00000000 00400490 004004a4
    00000000 <End of list>

$

-- no sign of the ISA bit anywhere -- line info:

$ mips-linux-gnu-readelf -wl foobar
Raw dump of debug contents of section .debug_line:
[...]
  Offset:                      0x27
  Length:                      78
  DWARF Version:               2
  Prologue Length:             31
  Minimum Instruction Length:  1
  Initial value of 'is_stmt':  1
  Line Base:                   -5
  Line Range:                  14
  Opcode Base:                 13

 Opcodes:
  Opcode 1 has 0 args
  Opcode 2 has 1 args
  Opcode 3 has 1 args
  Opcode 4 has 1 args
  Opcode 5 has 1 args
  Opcode 6 has 0 args
  Opcode 7 has 0 args
  Opcode 8 has 0 args
  Opcode 9 has 1 args
  Opcode 10 has 0 args
  Opcode 11 has 0 args
  Opcode 12 has 1 args

 The Directory Table is empty.

 The File Name Table:
  Entry Dir     Time    Size    Name
  1     0       0       0       foobar.c

 Line Number Statements:
  Extended opcode 2: set Address to 0x400681
  Special opcode 6: advance Address by 0 to 0x400681 and Line by 1 to 2
  Special opcode 7: advance Address by 0 to 0x400681 and Line by 2 to 4
  Special opcode 55: advance Address by 3 to 0x400684 and Line by 8 to 12
  Special opcode 7: advance Address by 0 to 0x400684 and Line by 2 to 14
  Advance Line by -7 to 7
  Special opcode 131: advance Address by 9 to 0x40068d and Line by 0 to 7
  Special opcode 7: advance Address by 0 to 0x40068d and Line by 2 to 9
  Advance PC by 3 to 0x400690
  Extended opcode 1: End of Sequence

  Extended opcode 2: set Address to 0x400491
  Advance Line by 21 to 22
  Copy
  Special opcode 6: advance Address by 0 to 0x400491 and Line by 1 to 23
  Special opcode 60: advance Address by 4 to 0x400495 and Line by -1 to 22
  Special opcode 34: advance Address by 2 to 0x400497 and Line by 1 to 23
  Special opcode 62: advance Address by 4 to 0x40049b and Line by 1 to 24
  Special opcode 32: advance Address by 2 to 0x40049d and Line by -1 to 23
  Special opcode 6: advance Address by 0 to 0x40049d and Line by 1 to 24
  Advance PC by 7 to 0x4004a4
  Extended opcode 1: End of Sequence
[...]

-- a-ha, the ISA bit is there!  However it's not always right for some
reason, I don't have a small test case to show it, but here's an excerpt
from MIPS16 libc, a prologue of a function:

00019630 <__libc_init_first>:
   19630:       e8a0            jrc     ra
   19632:       6500            nop

00019634 <_init>:
   19634:       f000 6a11       li      v0,17
   19638:       f7d8 0b08       la      v1,15e00 <_DYNAMIC+0x15c54>
   1963c:       f400 3240       sll     v0,16
   19640:       e269            addu    v0,v1
   19642:       659a            move    gp,v0
   19644:       64f6            save    48,ra,s0-s1
   19646:       671c            move    s0,gp
   19648:       d204            sw      v0,16(sp)
   1964a:       f352 984c       lw      v0,-27828(s0)
   1964e:       6724            move    s1,a0

and the corresponding DWARF-2 line info:

 Line Number Statements:
  Extended opcode 2: set Address to 0x19631
  Advance Line by 44 to 45
  Copy
  Special opcode 8: advance Address by 0 to 0x19631 and Line by 3 to 48
  Special opcode 66: advance Address by 4 to 0x19635 and Line by 5 to 53
  Advance PC by constant 17 to 0x19646
  Special opcode 25: advance Address by 1 to 0x19647 and Line by 6 to 59
  Advance Line by -6 to 53
  Special opcode 33: advance Address by 2 to 0x19649 and Line by 0 to 53
  Special opcode 39: advance Address by 2 to 0x1964b and Line by 6 to 59
  Advance Line by -6 to 53
  Special opcode 61: advance Address by 4 to 0x1964f and Line by 0 to 53

-- see that "Advance PC by constant 17" there?  It clears the ISA bit,
however code at 0x19646 is not standard MIPS code at all.  For some
reason the constant is always 17, I've never seen DW_LNS_const_add_pc
used with any other value -- is that a binutils bug or what?

3. Solution:

I think we should retain the value of the ISA bit in code references,
that is effectively treat them as cookies as they indeed are (although
trivially calculated) rather than raw memory byte addresses.

In a perfect world both the static symbol table and the respective
DWARF-2 records should be fixed to include the ISA bit in all the cases.
I think however that this is infeasible.

All the uses of `_bfd_mips_elf_symbol_processing' can not necessarily be
tracked down.  This function is used by `elf_slurp_symbol_table' that in
turn is used by `bfd_canonicalize_symtab' and
`bfd_canonicalize_dynamic_symtab', which are public interfaces.

Similarly DWARF-2 records are used outside GDB, one notable if a bit
questionable is the exception unwinder (libgcc/unwind-dw2.c) -- I have
identified at least bits in `execute_cfa_program' and
`uw_frame_state_for', both around the calls to `_Unwind_IsSignalFrame',
that would need an update as they effectively flip the ISA bit freely;
see also the comment about MASK_RETURN_ADDR in gcc/config/mips/mips.h.
But there may be more places.  Any change in how DWARF-2 records are
produced would require an update there and would cause compatibility
problems with libgcc.a binaries already distributed; given that this is
a static library a complex change involving function renames would
likely be required.

I propose therefore to accept the existing inconsistencies and deal with
them entirely within GDB.  I have figured out that the ISA bit lost in
various places can still be recovered as long as we have symbol
information -- that'll have the `st_other' attribute correctly set to
one of standard MIPS/MIPS16/microMIPS encoding.

Here's the resulting change.  It adds a couple of new `gdbarch' hooks,
one to update symbol information with the ISA bit lost in
`_bfd_mips_elf_symbol_processing', and two other ones to adjust DWARF-2
records as they're processed.  The ISA bit is set in each address
handled according to information retrieved from the symbol table for the
symbol spanning the address if any; limits are adjusted based on the
address they point to related to the respective base address.
Additionally minimal symbol information has to be adjusted accordingly
in its gdbarch hook.

With these changes in place some complications with ISA bit juggling in
the PC that never fully worked can be removed from the MIPS backend.
Conversely, the generic dynamic linker event special breakpoint symbol
handler has to be updated to call the minimal symbol gdbarch hook to
record that the symbol is a MIPS16 or microMIPS address if applicable or
the breakpoint will be set at the wrong address and either fail to work
or cause SIGTRAPs (this is because the symbol is handled early on and
bypasses regular symbol processing).

4. Results obtained

The change fixes the example above -- to repeat only the crucial steps:

(gdb) break main
Breakpoint 1 at 0x400491: file foobar.c, line 23.
(gdb) run
Starting program: .../foobar

Breakpoint 1, main () at foobar.c:23
23        return foop ();
(gdb) print foo
$1 = {int (void)} 0x400681 <foo>
(gdb) set foop = bar
(gdb) advance bar
bar () at foobar.c:9
9       }
(gdb) disassemble
Dump of assembler code for function bar:
=> 0x0040068d <+0>:     jr      ra
   0x0040068f <+2>:     li      v0,2
End of assembler dump.
(gdb) finish
Run till exit from #0  bar () at foobar.c:9
main () at foobar.c:24
24      }
Value returned is $2 = 2
(gdb) continue
Continuing.
[Inferior 1 (process 14128) exited with code 02]
(gdb)

-- excellent!

The change removes about 90 failures per MIPS16 multilib in mips-sde-elf
testing too, results for MIPS16 are now similar to that for standard
MIPS; microMIPS results are a bit worse because of host-I/O problems in
QEMU used instead of MIPSsim for microMIPS testing only:

                === gdb Summary ===

# of expected passes            14299
# of unexpected failures        187
# of expected failures          56
# of known failures             58
# of unresolved testcases       11
# of untested testcases         52
# of unsupported tests          174

MIPS16:

                === gdb Summary ===

# of expected passes            14298
# of unexpected failures        187
# of unexpected successes       2
# of expected failures          54
# of known failures             58
# of unresolved testcases       12
# of untested testcases         52
# of unsupported tests          174

microMIPS:

                === gdb Summary ===

# of expected passes            14149
# of unexpected failures        201
# of unexpected successes       2
# of expected failures          54
# of known failures             58
# of unresolved testcases       7
# of untested testcases         53
# of unsupported tests          175

2014-12-12  Maciej W. Rozycki  <macro@codesourcery.com>
            Maciej W. Rozycki  <macro@mips.com>
            Pedro Alves  <pedro@codesourcery.com>

	gdb/
	* gdbarch.sh (elf_make_msymbol_special): Change type to `F',
	remove `predefault' and `invalid_p' initializers.
	(make_symbol_special): New architecture method.
	(adjust_dwarf2_addr, adjust_dwarf2_line): Likewise.
	(objfile, symbol): New declarations.
	* arch-utils.h (default_elf_make_msymbol_special): Remove
	prototype.
	(default_make_symbol_special): New prototype.
	(default_adjust_dwarf2_addr): Likewise.
	(default_adjust_dwarf2_line): Likewise.
	* mips-tdep.h (mips_unmake_compact_addr): New prototype.
	* arch-utils.c (default_elf_make_msymbol_special): Remove
	function.
	(default_make_symbol_special): New function.
	(default_adjust_dwarf2_addr): Likewise.
	(default_adjust_dwarf2_line): Likewise.
	* dwarf2-frame.c (decode_frame_entry_1): Call
	`gdbarch_adjust_dwarf2_addr'.
	* dwarf2loc.c (dwarf2_find_location_expression): Likewise.
	* dwarf2read.c (create_addrmap_from_index): Likewise.
	(process_psymtab_comp_unit_reader): Likewise.
	(add_partial_symbol): Likewise.
	(add_partial_subprogram): Likewise.
	(process_full_comp_unit): Likewise.
	(read_file_scope): Likewise.
	(read_func_scope): Likewise.  Call `gdbarch_make_symbol_special'.
	(read_lexical_block_scope): Call `gdbarch_adjust_dwarf2_addr'.
	(read_call_site_scope): Likewise.
	(dwarf2_ranges_read): Likewise.
	(dwarf2_record_block_ranges): Likewise.
	(read_attribute_value): Likewise.
	(dwarf_decode_lines_1): Call `gdbarch_adjust_dwarf2_line'.
	(new_symbol_full): Call `gdbarch_adjust_dwarf2_addr'.
	* elfread.c (elf_symtab_read): Don't call
	`gdbarch_elf_make_msymbol_special' if unset.
	* mips-linux-tdep.c (micromips_linux_sigframe_validate): Strip
	the ISA bit from the PC.
	* mips-tdep.c (mips_unmake_compact_addr): New function.
	(mips_elf_make_msymbol_special): Set the ISA bit in the symbol's
	address appropriately.
	(mips_make_symbol_special): New function.
	(mips_pc_is_mips): Set the ISA bit before symbol lookup.
	(mips_pc_is_mips16): Likewise.
	(mips_pc_is_micromips): Likewise.
	(mips_pc_isa): Likewise.
	(mips_adjust_dwarf2_addr): New function.
	(mips_adjust_dwarf2_line): Likewise.
	(mips_read_pc, mips_unwind_pc): Keep the ISA bit.
	(mips_addr_bits_remove): Likewise.
	(mips_skip_trampoline_code): Likewise.
	(mips_write_pc): Don't set the ISA bit.
	(mips_eabi_push_dummy_call): Likewise.
	(mips_o64_push_dummy_call): Likewise.
	(mips_gdbarch_init): Install `mips_make_symbol_special',
	`mips_adjust_dwarf2_addr' and `mips_adjust_dwarf2_line' gdbarch
	handlers.
	* solib.c (gdb_bfd_lookup_symbol_from_symtab): Get
	target-specific symbol address adjustments.
	* gdbarch.h: Regenerate.
	* gdbarch.c: Regenerate.

2014-12-12  Maciej W. Rozycki  <macro@codesourcery.com>

	gdb/testsuite/
	* gdb.base/func-ptrs.c: New file.
	* gdb.base/func-ptrs.exp: New file.
2014-12-12 13:49:06 +00:00
Simon Marchi
fc1269757f Only leave dprintf inserted if it is marked as persistent (PR breakpoints/17012)
On Linux native, if dprintfs are inserted when detaching, they are left
in the inferior which causes it to crash from a SIGTRAP. It also happens
with dprintfs on remote targets, when set disconnected-dprintf is off.

The rationale of the line modified by the patch was to leave dprintfs
inserted in order to support disconnected dprintfs. However, not all
dprintfs are persistent. Also, there's no reason other kinds of
breakpoints can't be persistent either. So this replaces the bp_dprintf
check with a check on whether the location is persistent.

bl->target_info.persist will be 1 only if disconnected-dprintf is on and
we are debugging a remote target. On native, it will always be 0,
regardless of the value of disconnected-dprintf. This makes sense, since
disconnected dprintfs are not supported by the native target.

One issue about the test is that it does not pass when using
--target_board=native-extended-gdbserver, partly due to bug 17302 [1].

One quick hack I tried for this was to add a useless "next" between the
call to getpid() and detach, which avoids the bug. There is still one
case where the test fails, and that is with:

- breakpoint always-inserted on
- dprintf-style agent
- disconnected-dprintf on

What happens is that my detach does not actually detach the process,
because some persistent commands (the disconnected dprintf) is present.
However since gdbserver is ran with --once, when gdb disconnects,
gdbserver goes down and takes with it all the processes it spawned and
that are still under its control (which includes my test process).
When the test checks if the test process is still alive, it obvisouly
fails. Investigating about that led me to ask a question on the ML [2]
about the behavior of detach.

Until the remote case is sorted out, the problematic test is marked as
KFAIL.

[1] https://sourceware.org/bugzilla/show_bug.cgi?id=17302
[2] https://sourceware.org/ml/gdb/2014-08/msg00115.html

gdb/Changelog:

	PR breakpoints/17012
	* breakpoint.c (remove_breakpoints_pid): Skip removing
	breakpoint if it is marked as persistent.

gdb/testsuite/ChangeLog:

	PR breakpoints/17012
	* gdb.base/dprintf-detach.c: New file.
	* gdb.base/dprintf-detach.exp: New file.
2014-12-10 16:10:05 -05:00
Simon Marchi
0a46d518c7 Introduce target_is_gdbserver
This patch introduces a function in gdbserver-support.exp to find out
whether the current target is GDBserver.

The code was inspired from gdb.trace/qtro.exp, so it replaces the code
there by a call to the new function.

gdb/testsuite/ChangeLog:

	* gdb.trace/qtro.exp: Replace gdbserver detection code by...
	* lib/gdb.exp (target_is_gdbserver): New
	procedure.
2014-12-10 15:12:17 -05:00
Doug Evans
a0be3e44c7 New "owner" attribute for gdb.Objfile.
gdb/ChangeLog:

	* NEWS: Mention gdb.Objfile.owner.
	* python/py-objfile.c (objfpy_get_owner): New function.
	(objfile_getset): Add "owner".

gdb/doc/ChangeLog:

	* python.texi (Objfiles In Python): Document Objfile.owner.

gdb/testsuite/ChangeLog:

	* gdb.python/py-objfile.exp: Add tests for objfile.owner.
2014-12-08 08:50:48 -08:00
Yao Qi
df1b803ada Fix parallel testing issues in gdb.guile tests
Some gdb.guile tests such as scm-error.exp copies .scm file to
${subdir}/, how ${subdir} doesn't exist in parallel testing
(outputs/${subdir} exists).

$ make -j3 check TESTS='gdb.guile/scm-section-script.exp gdb.guile/scm-error.exp gdb.guile/scm-frame-args.exp'

ERROR: remote_download to host of ../../../../git/gdb/testsuite/gdb.guile/scm-section-script.scm to gdb.guile/t-scm-section-script.scm: cp: cannot create regular file 'gdb.guile/t-scm-section-script.scm': No such file or directory
ERROR: remote_download to host of ../../../../git/gdb/testsuite/gdb.guile/scm-frame-args.scm to gdb.guile/t-scm-frame-args.scm: cp: cannot create regular file
'gdb.guile/t-scm-frame-args.scm': No such file or directory
ERROR: remote_download to host of ../../../../git/gdb/testsuite/gdb.guile/scm-error-1.scm to gdb.guile/t-scm-error-1.scm: cp: cannot create regular file 'gdb.guile/t-scm-error-1.scm': No such file or directory

This patch is to remove the third argument of gdb_remote_download, so
that gdb_remote_download can return the correct location.

Further, these tests only copy .scm files to a different name.  From what
I can tell from the comments, looks we do this to avoid clobbering file
in in-tree build.  However, if source and dest of copy are the same, the
operation is no-op.  So it makes few sense to copy .scm files to a
different names.  I tried in-tree build/test with this patch, test
result isn't changed.

gdb/testsuite:

2014-12-05  Yao Qi  <yao@codesourcery.com>

	* gdb.guile/scm-error.exp: Remove the third argument to
	gdb_remote_download.
	* gdb.guile/scm-frame-args.exp: Likewise.
	* gdb.guile/scm-section-script.exp: Likewise.
2014-12-05 19:45:04 +08:00
Yao Qi
ddb9f679fa Use standard_testfile in i386-bp_permanent.exp
This patch is to use standard_testfile in i386-bp_permanent.exp to replace
existing setting to testfile, srcfile and binfile.  So it fixes a problem
in i386-bp_permanent.exp in parallel testing.

$ make -j3 check TESTS='gdb.guile/scm-section-script.exp gdb.arch/i386-bp_permanent.exp'
....
gdb compile failed, /usr/bin/ld: cannot open output file x86/gdb/testsuite/gdb.arch/i386-bp_permanent: No such file or directory
collect2: error: ld returned 1 exit status

gdb/testsuite:

2014-12-05  Yao Qi  <yao@codesourcery.com>

	* gdb.arch/i386-bp_permanent.exp: Use standard_testfile.
2014-12-05 15:32:00 +08:00
Doug Evans
86e4ed3959 New python method gdb.Objfile.add_separate_debug_file.
gdb/ChangeLog:

	* NEWS: Mention gdb.Objfile.add_separate_debug_file.
	* python/py-objfile.c (objfpy_add_separate_debug_file): New function.
	(objfile_getset): Add "add_separate_debug_file".

gdb/doc/ChangeLog:

	* python.texi (Objfiles In Python): Document
	Objfile.add_separate_debug_file.

gdb/testsuite/ChangeLog:

	* gdb.python/py-objfile.exp: Add tests for
	objfile.add_separate_debug_file.
2014-12-04 12:01:22 -08:00
Doug Evans
7c50a93137 New python attribute gdb.Objfile.build_id.
gdb/ChangeLog:

	* NEWS: Mention gdb.Objfile.build_id.
	* build-id.c (build_id_bfd_get): Make non-static.
	* build-id.h (build_id_bfd_get): Add declaration.
	* python/py-objfile.c: #include "build-id.h", "elf-bfd.h".
	(OBJFPY_REQUIRE_VALID): New macro.
	(objfpy_get_build_id): New function.
	(objfile_getset): Add "build_id".
	* utils.c (make_hex_string): New function.
	* utils.h (make_hex_string): Add declaration.

gdb/doc/ChangeLog:

	* python.texi (Objfiles In Python): Document Objfile.build_id.

gdb/testsuite/ChangeLog:

	* lib/gdb.exp (get_build_id): New function.
	(build_id_debug_filename_get): Rewrite to use it.
	* gdb.python/py-objfile.exp: Add test for objfile.build_id.
2014-12-04 11:32:24 -08:00
Maciej W. Rozycki
621661e3fa Correct invalid assumptions made by (mostly) DWARF-2 tests
Address issues triggered by the MIPS ISA bit handling change, usually in
tests that make artificial DWARF-2 records:

* gdb.cp/expand-psymtabs-cxx.exp -- this test is debugging an object file
  and assuming addresses will be 0; with the ISA bit set code addresses
  are 1 instead:

(gdb) PASS: gdb.cp/expand-psymtabs-cxx.exp: set language c++
p 'method(long)'
$1 = {void (long)} 0x1 <method(long)>
(gdb) FAIL: gdb.cp/expand-psymtabs-cxx.exp: before expand
p method
$2 = {void (long)} 0x1 <method(long)>
(gdb) FAIL: gdb.cp/expand-psymtabs-cxx.exp: force expand
p 'method(long)'
$3 = {void (long)} 0x1 <method(long)>
(gdb) FAIL: gdb.cp/expand-psymtabs-cxx.exp: after expand

  Fix by matching any hex number, there's no value AFAICT for the test
  in matching 0 exactly, and I suppose the method's offset within
  section can be non-zero for some other reasons on other targets too.

* gdb.cp/nsalias.exp -- this assumes instructions can be aligned
  arbitrarily and places code labels at odd addreses, setting the ISA
  bit and wreaking havoc:

(gdb) PASS: gdb.cp/nsalias.exp: print outer::inner::innermost::x
list outer::inner::innermost::foo
Function "outer::inner::innermost::foo" not defined.
(gdb) FAIL: gdb.cp/nsalias.exp: list outer::inner::innermost::foo
break *outer::inner::innermost::foo
No symbol "foo" in namespace "outer::inner::innermost".
(gdb) FAIL: gdb.cp/nsalias.exp: setting breakpoint at
*outer::inner::innermost::foo
delete $bpnum
No breakpoint number 6.
(gdb) FAIL: gdb.cp/nsalias.exp: (outer::inner::innermost): delete $bpnum

  -- etc., etc...  Fix by aligning labels to 4; required by many
  processors.

* gdb.dwarf2/dw2-canonicalize-type.exp, gdb.dwarf2/dw2-empty-pc-range.exp,
  gdb.dwarf2/pr11465.exp -- these assume an instruction and consequently
  a function can take as little as 1 byte, which makes it impossible to
  look up a code symbol by an address with the ISA bit set as the
  address is already beyond the end of the function:

(gdb) ptype f
No symbol "f" in current context.
(gdb) FAIL: gdb.dwarf2/dw2-canonicalize-type.exp: ptype f

(gdb) PASS: gdb.dwarf2/dw2-empty-pc-range.exp: empty range before CU load
ptype realrange
No symbol "realrange" in current context.
(gdb) FAIL: gdb.dwarf2/dw2-empty-pc-range.exp: valid range after CU load

(gdb) p N::c.C
Cannot take address of method C.
(gdb) FAIL: gdb.dwarf2/pr11465.exp: p N::c.C

  -- fix by increasing the size of the function to 4 (perhaps code in
  gdb/mips-tdep.c could look up code symbols up to twice, with and
  failing that without the ISA bit set, but it seems wrong to me to
  implement specific handling for invalid code just to satisfy test
  cases that assume too much about the target).

* gdb.dwarf2/dw2-case-insensitive.exp -- an artificial code label is
  created, but does not work because data (a `.align' pseudo-op in this
  case) follows and as a result the label has no MIPS16 or microMIPS
  annotation in the symbol table:

(gdb) PASS: gdb.dwarf2/dw2-case-insensitive.exp: set case-sensitive off
info functions fUnC_lang
All functions matching regular expression "fUnC_lang":

File file1.txt:
foo FUNC_lang(void);

Non-debugging symbols:
0x004006e0  FUNC_lang_start
(gdb) FAIL: gdb.dwarf2/dw2-case-insensitive.exp: regexp case-sensitive off

  -- fix by adding a `.insn' pseudo-op on MIPS targets; the pseudo-op
  marks data as instructions.

* gdb.dwarf2/dw2-stack-boundary.exp -- the test case enables complaints
  and assumes none will be issued beyond ones explicitly arranged by the
  test case, however overlapping sections are noticed while minimal
  symbols are looked up by `mips_adjust_dwarf2_addr' in DWARF-2 record
  processing:

(gdb) set complaints 100
(gdb) PASS: gdb.dwarf2/dw2-stack-boundary.exp: set complaints 100
file ./dw2-stack-boundary
Reading symbols from ./dw2-stack-boundary...location description stack
underflow...location description stack overflow...unexpected overlap
between:
 (A) section `.reginfo' from `.../gdb.dwarf2/dw2-stack-boundary' [0x0, 0x18)
 (B) section `*COM*' from `.../gdb.dwarf2/dw2-stack-boundary' [0x0, 0x0).
Will ignore section B...unexpected overlap between:
 (A) section `.reginfo' from `.../gdb.dwarf2/dw2-stack-boundary' [0x0, 0x18)
 (B) section `*UND*' from `.../gdb.dwarf2/dw2-stack-boundary' [0x0, 0x0).
Will ignore section B...unexpected overlap between:
 (A) section `.reginfo' from `.../gdb.dwarf2/dw2-stack-boundary' [0x0, 0x18)
 (B) section `*ABS*' from `.../gdb.dwarf2/dw2-stack-boundary' [0x0, 0x0).
Will ignore section B...done.

(gdb) FAIL: gdb.dwarf2/dw2-stack-boundary.exp: check partial symtab errors

  -- fix by ignoring any extra noise as long as what we look for is
  found.

	* gdb.cp/expand-psymtabs-cxx.exp: Accept any address of
	`method(long)', not just 0x0.
	* gdb.cp/nsalias.exp: Align code labels to 4.
	* gdb.dwarf2/dw2-canonicalize-type.S (main): Expand to 4-bytes.
	* gdb.dwarf2/dw2-empty-pc-range.S (main): Likewise.
	* gdb.dwarf2/pr11465.S (_ZN1N1cE): Likewise.
	* gdb.dwarf2/dw2-case-insensitive.c (START_INSNS): New macro.
	(cu_text_start, FUNC_lang_start): Use `START_INSNS'.
	* gdb.dwarf2/dw2-stack-boundary.exp: Accept noise in complaints.
2014-12-04 00:06:10 +00:00
Doug Evans
29f0c3b7b2 PR symtab/17602
gdb/ChangeLog:

	PR symtab/17602
	* linespec.c (iterate_name_matcher): Fix arguments to symbol_name_cmp.

gdb/testsuite/ChangeLog:

        PR symtab/17602
	* gdb.cp/anon-ns.cc: Move guts of this file to ...
	* gdb.cp/anon-ns-2.cc: ... here.  New file.
	* gdb.cp/anon-ns.exp: Update.
2014-12-02 16:40:38 -08:00
Nick Bull
162078c893 New python events: inferior call, register/memory changed.
gdb/ChangeLog:

	* NEWS: Mention new Python events.
	* Makefile.in (SUBDIR_PYTHON_OBS): Add py-infevents.o.
	(SUBDIR_PYTHON_SRCS): Add py-infevents.c.
	(py-infevents.o): New rule.
	* doc/observer.texi (inferior_call_pre, inferior_call_post)
	(memory_changed, register_changed): New observers.
	* infcall.c (call_function_by_hand): Notify observer before and
	after inferior call.
	* python/py-event.h (inferior_call_kind): New enum.
	(emit_inferior_call_event): New prototype.
	(emit_register_changed_event): New prototype.
	(emit_memory_changed_event): New prototype.
	* python/py-events.h (events_object): New registries
	inferior_call, memory_changed and register_changed.
	* python/py-evts.c (gdbpy_initialize_py_events): Add the
	inferior_call, memory_changed and register_changed registries.
	* python/py-infevents.c: New.
	* python/py-inferior.c (python_on_inferior_call_pre)
	(python_on_inferior_call_post, python_on_register_change)
	(python_on_memory_change): New functions.
	(gdbpy_initialize_inferior): Attach python handler to new
	observers.
	* python/py-infthread.c(gdbpy_create_ptid_object): New.
	(thpy_get_ptid) Use gdbpy_create_ptid_object.
	* python/python-internal.h:
	(gdbpy_create_ptid_object)
	(gdbpy_initialize_inferior_call_pre_event)
	(gdbpy_initialize_inferior_call_post_event)
	(gdbpy_initialize_register_changed_event)
	(gdbpy_initialize_memory_changed_event): New prototypes.
	* python/python.c (_initialize_python): Initialize new events.
	* valops.c (value_assign): Notify register_changed observer.

gdb/doc/ChangeLog:

	* python.texi (Events In Python): Document new events
	InferiorCallPreEvent, InferiorCallPostEvent, MemoryChangedEvent
	and RegisterChangedEvent.

gdb/testsuite/ChangeLog:

	* gdb.python/py-events.py (inferior_call_handler): New.
	(register_changed_handler, memory_changed_handler): New.
	(test_events.invoke): Register new handlers.
	* gdb.python/py-events.exp: Add tests for inferior call,
	memory_changed and register_changed events.
2014-12-02 11:15:29 -08:00
Doug Evans
71dd4b30a7 revert previous patch so that I can re-commit with correct author 2014-12-02 11:12:49 -08:00
Doug Evans
dc6c87175b New python events: infcall, register/memory changed.
gdb/ChangeLog:

	* NEWS: Mention new Python events.
	* Makefile.in (SUBDIR_PYTHON_OBS): Add py-infevents.o.
	(SUBDIR_PYTHON_SRCS): Add py-infevents.c.
	(py-infevents.o): New rule.
	* doc/observer.texi (inferior_call_pre, inferior_call_post)
	(memory_changed, register_changed): New observers.
	* infcall.c (call_function_by_hand): Notify observer before and
	after inferior call.
	* python/py-event.h (inferior_call_kind): New enum.
	(emit_inferior_call_event): New prototype.
	(emit_register_changed_event): New prototype.
	(emit_memory_changed_event): New prototype.
	* python/py-events.h (events_object): New registries
	inferior_call, memory_changed and register_changed.
	* python/py-evts.c (gdbpy_initialize_py_events): Add the
	inferior_call, memory_changed and register_changed registries.
	* python/py-infevents.c: New.
	* python/py-inferior.c (python_on_inferior_call_pre)
	(python_on_inferior_call_post, python_on_register_change)
	(python_on_memory_change): New functions.
	(gdbpy_initialize_inferior): Attach python handler to new
	observers.
	* python/py-infthread.c(gdbpy_create_ptid_object): New.
	(thpy_get_ptid) Use gdbpy_create_ptid_object.
	* python/python-internal.h:
	(gdbpy_create_ptid_object)
	(gdbpy_initialize_inferior_call_pre_event)
	(gdbpy_initialize_inferior_call_post_event)
	(gdbpy_initialize_register_changed_event)
	(gdbpy_initialize_memory_changed_event): New prototypes.
	* python/python.c (_initialize_python): Initialize new events.
	* valops.c (value_assign): Notify register_changed observer.

gdb/doc/ChangeLog:

	* python.texi (Events In Python): Document new events
	InferiorCallPreEvent, InferiorCallPostEvent, MemoryChangedEvent
	and RegisterChangedEvent.

gdb/testsuite/ChangeLog:

	* gdb.python/py-events.py (inferior_call_handler): New.
	(register_changed_handler, memory_changed_handler): New.
	(test_events.invoke): Register new handlers.
	* gdb.python/py-events.exp: Add tests for inferior call,
	memory_changed and register_changed events.
2014-12-02 10:59:08 -08:00
Andreas Arnez
fdb09caf23 execl-update-breakpoints.exp: Move whole segment instead of .text section
The test case builds two copies of the program, one with the compile
option "ldflags=-Wl,-Ttext=0x1000000" and the other with the address
changed to 0x2000000.  However, when linking with ld.bfd, the
resulting executables crash early in ld.so on S390 and i386.

Analysis of the crash: The default linker script establishes a certain
order of loadable sections, and the option "-Ttext" effectively splits
these into an "unaffected" lot (everything before .text) and an
"affected" lot.  The affected lot is placed at the given address,
whereas the unaffected lot stays at its default address.  The
unaffected lot starts at an aligned address plus Elf header sizes,
which is good if it is the first LOAD segment (like on AMD64).  But if
the affected lot comes first instead (like on S390 and i386), the PHDR
doesn't fit there and is placed *outside* any LOAD segments.  Then the
PHDR is not mapped when the loader gets control, and the loader runs
into a segmentation fault while trying to access it.

Since we are lucky about the order of segments on AMD64, the test
succeeds there, but the resulting binaries are unusually large -- 2.1M
each, with lots of padding within.

When replacing '-Ttext' by '-Ttext-segment', the linker moves all
segments consistently, the binaries have normal sizes, and the test
case succeeds on all mentioned platforms.

Since old versions of the gold linker don't support '-Ttext-segment',
the patch also adds logic for falling back to '-Ttext'.

gdb/testsuite/ChangeLog:

	* gdb.base/execl-update-breakpoints.exp: Specify the link address
	with '-Ttext-segment' instead of '-Ttext'.  Fall back to '-Ttext'
	if the linker doesn't understand this.
2014-12-02 16:35:47 +01:00
Simon Marchi
55cfb2c4c8 Fix Python help() test for Python 3
The message displayed when using help() changed a bit with time, so this
adjusts the test accordingly.

gdb/testsuite/ChangeLog:

	* gdb.python/python.exp: Change expected reply to help().
2014-12-01 08:08:06 -05:00
Yao Qi
9e8cd6df3c Don't enable gdbtk in testsuite
When I skim configure.ac and Makefile.in in gdb/testsuite, I happen to
see that directory gdb.gdbtk is added to subdirs, however it doesn't
exist.  gdb/testsuite/gdb.gdbtk was removed by the patch below,

  [rfa] git repo fixup: delete gdb/testsuite/gdb.gdbtk
  http://thread.gmane.org/gmane.comp.gdb.patches/61489

and we should cleanup configure.ac accordingly.

gdb/testsuite:

2014-12-01  Yao Qi  <yao@codesourcery.com>

	* configure.ac: Remove AC_ARG_ENABLE for gdbtk.  Don't invoke
	AC_CONFIG_SUBDIRS(gdb.gdbtk).
	* configure: Re-generated.
2014-12-01 14:13:17 +08:00
Siva Chandra
6c659fc2c7 Enable chained function calls in C++ expressions.
gdb/ChangeLog:

	* eval.c: Include gdbthread.h.
	(evaluate_subexp): Enable thread stack temporaries before
	evaluating a complete expression and clean them up after the
	evaluation is complete.
	* gdbthread.h: Include common/vec.h.
	(value_ptr): New typedef.
	(VEC (value_ptr)): New vector type.
	(value_vec): New typedef.
	(struct thread_info): Add new fields stack_temporaries_enabled
	and stack_temporaries.
	(enable_thread_stack_temporaries)
	(thread_stack_temporaries_enabled_p, push_thread_stack_temporary)
	(get_last_thread_stack_temporary)
	(value_in_thread_stack_temporaries): Declare.
	* gdbtypes.c (class_or_union_p): New function.
	* gdbtypes.h (class_or_union_p): Declare.
	* infcall.c (call_function_by_hand): Store return values of class
	type as	temporaries on stack.
	* thread.c (enable_thread_stack_temporaries): New function.
	(thread_stack_temporaries_enabled_p, push_thread_stack_temporary)
	(get_last_thread_stack_temporary): Likewise.
	(value_in_thread_stack_temporaries): Likewise.
	* value.c (value_force_lval): New function.
	* value.h (value_force_lval): Declare.

gdb/testsuite/ChangeLog:

	* gdb.cp/chained-calls.cc: New file.
	* gdb.cp/chained-calls.exp: New file.
	* gdb.cp/smartp.exp: Remove KFAIL for "p c2->inta".
2014-11-28 16:01:16 -08:00
Simon Marchi
d7fc3181f7 Fix prints in tests for Python 3
Python 3's print requires to use parentheses, so this patch adds them
where they were missing.

gdb/testsuite/ChangeLog:

	* gdb.ada/py_range.exp: Add parentheses to calls to print.
	* gdb.dwarf2/symtab-producer.exp: Same.
	* gdb.gdb/python-interrupts.exp: Same.
	* gdb.gdb/python-selftest.exp: Same.
	* gdb.python/py-linetable.exp: Same.
	* gdb.python/py-type.exp: Same.
	* gdb.python/py-value-cc.exp: Same.
	* gdb.python/py-value.exp: Same.
2014-11-28 11:36:52 -05:00