As a preparation for the next patch, which will move fork_inferior
from GDB to common/ (and therefore share it with gdbserver), it is
interesting to convert a few functions to C++.
This patch touches functions related to parsing command-line arguments
to the inferior (see gdb/fork-child.c:breakup_args), the way the
arguments are stored on fork_inferior (using std::vector instead of
char **), and the code responsible for dealing with argv also on
gdbserver.
I've taken this opportunity and decided to constify a few arguments to
fork_inferior/create_inferior as well, in order to make the code
cleaner. And now, on gdbserver, we're using xstrdup everywhere and
aren't checking for memory allocation failures anymore, as requested
by Pedro:
<https://sourceware.org/ml/gdb-patches/2017-03/msg00191.html>
Message-Id: <025ebdb9-90d9-d54a-c055-57ed2406b812@redhat.com>
Pedro Alves wrote:
> On the "== NULL" check: IIUC, the old NULL check was there to
> handle strdup returning NULL due to out-of-memory.
> See NULL checks and comments further above in this function.
> Now that you're using a std::vector, that doesn't work or make
> sense any longer, since if push_back fails to allocate space for
> its internal buffer (with operator new), our operator new replacement
> (common/new-op.c) calls malloc_failure, which aborts gdbserver.
>
> Not sure it makes sense to handle out-of-memory specially in
> the gdb/rsp-facing functions nowadays (maybe git blame/log/patch
> submission for that code shows some guidelines). Maybe (or, probably)
> it's OK to stop caring about it, but then we should consistently remove
> left over code, by using xstrdup instead and remove the NULL checks.
IMO this refactoring was very good to increase the readability of the
code as well, because some parts of the argument handling were
unnecessarily confusing before.
gdb/ChangeLog:
2017-04-12 Sergio Durigan Junior <sergiodj@redhat.com>
* common/common-utils.c (free_vector_argv): New function.
* common/common-utils.h: Include <vector>.
(free_vector_argv): New prototype.
* darwin-nat.c (darwin_create_inferior): Rewrite function
prototype in order to constify "exec_file" and accept a
"std::string" for "allargs".
* fork-child.c: Include <vector>.
(breakup_args): Rewrite function, using C++.
(fork_inferior): Rewrite function header, constify "exec_file_arg"
and accept "std::string" for "allargs". Update the code to
calculate "argv" based on "allargs". Update calls to "exec_fun"
and "execvp".
* gnu-nat.c (gnu_create_inferior): Rewrite function prototype in
order to constify "exec_file" and accept a "std::string" for
"allargs".
* go32-nat.c (go32_create_inferior): Likewise.
* inf-ptrace.c (inf_ptrace_create_inferior): Likewise.
* infcmd.c (run_command_1): Constify "exec_file". Use
"std::string" for inferior arguments.
* inferior.h (fork_inferior): Update prototype.
* linux-nat.c (linux_nat_create_inferior): Rewrite function
prototype in order to constify "exec_file" and accept a
"std::string" for "allargs".
* nto-procfs.c (procfs_create_inferior): Likewise.
* procfs.c (procfs_create_inferior): Likewise.
* remote-sim.c (gdbsim_create_inferior): Likewise.
* remote.c (extended_remote_run): Update code to accept
"std::string" as argument.
(extended_remote_create_inferior): Rewrite function prototype in
order to constify "exec_file" and accept a "std::string" for
"allargs".
* rs6000-nat.c (super_create_inferior): Likewise.
(rs6000_create_inferior): Likewise.
* target.h (struct target_ops) <to_create_inferior>: Likewise.
* windows-nat.c (windows_create_inferior): Likewise.
gdb/gdbserver/ChangeLog:
2017-04-12 Sergio Durigan Junior <sergiodj@redhat.com>
* server.c: Include <vector>.
<program_argv, wrapper_argv>: Convert to std::vector.
(start_inferior): Rewrite function to use C++.
(handle_v_run): Likewise. Update code that calculates the argv
based on the vRun packet; use C++.
(captured_main): Likewise.
I grew a bit tired of using ptid_get_{lwp,pid,tid} and friends, so I decided to
make it a bit easier to use by making it a proper class. The fields are now
private, so it's not possible to change a ptid_t field by mistake.
The new methods of ptid_t map to existing functions/practice like this:
ptid_t (pid, lwp, tid) -> ptid_build (pid, lwp, tid)
ptid_t (pid) -> pid_to_ptid (pid)
ptid.is_pid () -> ptid_is_pid (ptid)
ptid == other -> ptid_equal (ptid, other)
ptid != other -> !ptid_equal (ptid, other)
ptid.pid () -> ptid_get_pid (ptid)
ptid.lwp_p () -> ptid_lwp_p (ptid)
ptid.lwp () -> ptid_get_lwp (ptid)
ptid.tid_p () -> ptid_tid_p (ptid)
ptid.tid () -> ptid_get_tid (ptid)
ptid.matches (filter) -> ptid_match (ptid, filter)
I've replaced the implementation of the existing functions with calls to
the new methods. People are encouraged to gradually switch to using the
ptid_t methods instead of the functions (or we can change them all in
one pass eventually).
Also, I'm not sure if it's worth it (because of ptid_t's relatively
small size), but I have made the functions and methods take ptid_t
arguments by const reference instead of by value.
gdb/ChangeLog:
* common/ptid.h (struct ptid): Change to...
(class ptid_t): ... this.
<ptid_t>: New constructors.
<pid, lwp_p, lwp, tid_p, tid, is_pid, operator==, operator!=,
matches>: New methods.
<make_null, make_minus_one>: New static methods.
<pid>: Rename to...
<m_pid>: ...this.
<lwp>: Rename to...
<m_lwp>: ...this.
<tid>: Rename to...
<m_tid>: ...this.
(ptid_build, ptid_get_pid, ptid_get_lwp, ptid_get_tid, ptid_equal,
ptid_is_pid, ptid_lwp_p, ptid_tid_p, ptid_match): Take ptid arguments
as references, move comment to class ptid_t.
* common/ptid.c (null_ptid, minus_one_ptid): Initialize with
ptid_t static methods.
(ptid_build, pid_to_ptid, ptid_get_pid, ptid_get_tid,
ptid_equal, ptid_is_pid, ptid_lwp_p, ptid_tid_p, ptid_match):
Take ptid arguments as references, implement using ptid_t methods.
* unittests/ptid-selftests.c: New file.
* Makefile.in (SUBDIR_UNITTESTS_SRCS): Add
unittests/ptid-selftests.c.
(SUBDIR_UNITTESTS_OBS): Add unittests/ptid-selftests.o.
gdb/gdbserver/ChangeLog:
* server.c (handle_v_cont): Initialize thread_resume::thread
with null_ptid.
AFAIK GDB is now free from -Wwrite-strings warnings. A few warnings may
be left behind in some host-specific code, but those should be few and
easy to fix.
gdb/ChangeLog:
2017-04-05 Pedro Alves <palves@redhat.com>
* warning.m4 (build_warnings): Remove -Wno-write-strings.
* configure: Regenerate.
gdb/gdbserver/ChangeLog:
2017-04-05 Pedro Alves <palves@redhat.com>
* configure: Regenerate.
src/gdb/gdbserver/win32-low.c:1499:39: error: ISO C++ forbids converting a string constant to 'char*' [-Werror=write-strings]
ourstatus->value.execd_pathname = "Main executable";
^
This reporting via TARGET_WAITKIND_EXECD it's totally unnecessary.
get_child_debug_event returns a TARGET_WAITKIND_SPURIOUS by default,
which works just as well here, and is what the equivalent code in
gdb/windows-nat.c does too.
gdb/gdbserver/ChangeLog:
2017-04-05 Pedro Alves <palves@redhat.com>
* win32-low.c (get_child_debug_event)
<CREATE_PROCESS_DEBUG_EVENT>: Don't report TARGET_WAITKIND_EXECD.
Report TARGET_WAITKIND_SPURIOUS instead.
-Wwrite-strings flags this assignment as requiring a cast:
port = STDIO_CONNECTION_NAME;
because 'port' is a "char *", and STDIO_CONNECTION_NAME is a string
literal.
gdb/gdbserver/ChangeLog:
2017-04-05 Pedro Alves <palves@redhat.com>
* remote-utils.c (remote_prepare, remote_open): Constify.
* remote-utils.h (remote_prepare, remote_open): Constify.
* server.c (captured_main): Constify 'port' handling.
In some situations, the dependency tracking files in .deps can refer to
source files that were removed or renamed, leading to errors like:
make: *** No rule to make target `version.c', needed by `version.o'. Stop.
This patch makes the clean target clear the .deps directory, which gives
the user a chance to recover from the error wihtout knowing about the
internals of the build system.
It is already done for GDB. See here for more details:
https://sourceware.org/ml/gdb-patches/2009-03/msg00000.html
gdb/gdbserver/ChangeLog:
* Makefile.in (clean): Clear .deps.
I noticed that there were some missing files in gdbserver's gitignore
(some generated register format .c files). Of course the easy fix would
be to add those files to .gitignore, but I think we can do a better job,
so that we don't have to worry about adding generated files to
.gitignore or the clean Makefile target.
I suggest naming all generated source files -generated.c. This way, we
can use a single rule in .gitignore and do a "rm -f *-generated.c" to
clean them up.
New in v2:
- Don't rename version.o and xml-builtin.o
gdb/gdbserver/ChangeLog:
* .gitignore: Remove generated files, replace with wildcard.
* (clean): Replace removal of generated files with wildcard.
(version.c): Replace with...
(version-generated.c): ...this.
(xml-builtin.c): Replace with...
(xml-builtin-generated.c): ...this.
(%-ipa.o: %-generated.c, %.o: %-generated.c): New rules.
(%.c: *regformats*): Replace with...
(%-generated.c: *regformats*): ...this.
Provide aceess to the THREADPTR register to remote gdb.
gdb/gdbserver/
2017-03-27 Max Filippov <jcmvbkbc@gmail.com>
* linux-xtensa-low.c (regnum::R_THREADPTR): New enum member.
(xtensa_fill_gregset): Call collect_register_by_name for
threadptr register.
(xtensa_store_gregset): Call supply_register_by_name for
threadptr register.
Correctly handle a0- registers on requests from remote gdb. This fixes
'Register 1 is not available'
and subsequent assertion in the remote gdb connecting to the gdbserver:
'findvar.c:291: internal-error: value_of_register_lazy:
Assertion `frame_id_p(get_frame_id (frame))' failed.'
The register structure is the same for windowed and call0 ABIs because
currently linux kernel internally requires windowed registers, so they
are always present.
gdb/gdbserver/
2017-03-27 Max Filippov <jcmvbkbc@gmail.com>
* linux-xtensa-low.c (xtensa_fill_gregset): Call collect_register
for all registers in a0_regnum..a0_regnum + C0_NREGS range.
(xtensa_store_gregset): Call supply_register for all registers in
a0_regnum..a0_regnum + C0_NREGS range.
We will need access to the environment functions when we share
fork_inferior between GDB and gdbserver, therefore we simply make the
API on gdb/environ.[ch] available on common/. No extra adjustments
are needed to make it compile on gdbserver.
gdb/ChangeLog:
2017-03-07 Sergio Durigan Junior <sergiodj@redhat.com>
* Makefile.in (SFILES): Replace "environ.c" with
"common/environ.c".
(HFILES_NO_SRCDIR): Likewise, for "environ.h".
* environ.c: Include "common-defs.h" instead of "defs.h. Moved
to...
* common/environ.c: ... here.
* environ.h: Moved to...
* common/environ.h: ... here.
gdb/gdbserver/ChangeLog:
2017-03-07 Sergio Durigan Junior <sergiodj@redhat.com>
* Makefile.in (SFILES): Add "common/environ.c".
(OBJS): Add "common/environ.h".
The size of the state-component bitmap as specified in
Intel(R) 64 and IA-32 Architectures Software Developer's Manual,
Chapter 13.4.2 is 8 bytes.
So far, the data types used for xstate_bv_p (gdb_byte*),
clear_bv (unsigned int) and tdep->xcr0 (uint64_t) were
inconsistent. But, since the xstate components were still
fitting into a single byte, the code still worked
as expected.
However, with the addition of the PKU feature (bit 9),
using one byte for the bitmap will no longer be sufficient.
This patch changes related code to use 64 bit data types
consistently and changes read/write acces of the XSAVE
header in the xsave buffer to use the endianess-aware
functions extract_unsigned_integer and store_unsigned_integer.
This is required to make sure that eventual differences
in endianess between host and target are taken care off.
gdb/Changelog:
2016-04-18 Michael Sturm <michael.sturm@intel.com>
* i387-tdep.c (i387_supply_xsave): Change type
of clear_bv to ULONGEST. Replace gdb_byte *xstate_bv_p
with ULONGEST xstate_bv and use extract_unsigned_integer
and store_unsigned_integer to read/write its value from
the xsave buffer.
(i387_collect_xsave): Replace gdb_byte *xstate_bv_p
with ULONGEST initial_xstate_bv and use
extract_unsigned_integer/store_unsigned_integer to
read/write its value from the xsave buffer.
Change type of clear_bv to ULONGEST.
gdbserver/Changelog:
2016-04-18 Michael Sturm <michael.sturm@intel.com>
* i387-fp.c (i387_cache_to_xsave): Change type of clear_bv to
unsigned long long.
(i387_fxsave_to_cache): Likewise.
Change-Id: I0de254158960b4f7bcbc9fe2fb857034fa1f7ca5
Signed-off-by: Michael Sturm <michael.sturm@intel.com>
This patch allows examination of the registers FS_BASE and GS_BASE
for Linux Systems running on 64bit. Tests for simple read and write
of the new registers is also added with this patch.
2017-01-27 Walfred Tedeschi <walfred.tedeschi@intel.com>
Richard Henderson <rth@redhat.com>
gdb/ChangeLog:
* amd64-linux-nat.c (PTRACE_ARCH_PRCTL): New define.
(amd64_linux_fetch_inferior_registers): Add case to fetch FS_BASE
GS_BASE for older kernels.
(amd64_linux_store_inferior_registers): Add case to store FS_BASE
GS_BASE for older kernels.
* amd64-linux-tdep.c (amd64_linux_gregset_reg_offset): Add FS_BASE
and GS_BASE to the offset table.
(amd64_linux_register_reggroup_p): Add FS_BASE and GS_BASE to the
system register group.
* amd64-nat.c (amd64_native_gregset_reg_offset): Implements case
for older kernels.
* amd64-tdep.c (amd64_init_abi): Add segment registers for the
amd64 ABI.
* amd64-tdep.h (amd64_regnum): Add AMD64_FSBASE_REGNUM and
AMD64_GSBASE_REGNUM.
(AMD64_NUM_REGS): Set to AMD64_GSBASE_REGNUM + 1.
* features/Makefile (amd64-linux.dat, amd64-avx-linux.dat)
(amd64-mpx-linux.dat, amd64-avx512-linux.dat, x32-linux.dat)
(x32-avx-linux.dat, x32-avx512-linux.dat): Add
i386/64bit-segments.xml in those rules.
* features/i386/64bit-segments.xml: New file.
* features/i386/amd64-avx-mpx-linux.xml: Add 64bit-segments.xml.
* features/i386/amd64-avx-linux.xml: Add 64bit-segments.xml.
* features/i386/amd64-avx512-linux.xml: Add 64bit-segments.xml.
* features/i386/amd64-mpx-linux.xml: Add 64bit-segments.xml.
* features/i386/x32-avx512-linux.xml: Add 64bit-segments.xml.
* features/i386/x32-avx-linux.xml: Add 64bit-segments.xml.
* features/i386/amd64-linux.xml: Add 64bit-segments.xml.
* features/i386/amd64-avx-linux.c: Regenerated.
* features/i386/amd64-avx-mpx-linux.c: Regenerated.
* features/i386/amd64-avx-mpx.c: Regenerated.
* features/i386/amd64-avx512-linux.c: Regenerated.
* features/i386/amd64-linux.c: Regenerated.
* features/i386/amd64-mpx-linux.c: Regenerated.
* features/i386/i386-avx-mpx-linux.c: Regenerated.
* features/i386/i386-avx-mpx.c: Regenerated.
* features/i386/x32-avx-linux.c: Regenerated.
* features/i386/x32-avx512-linux.c: Regenerated.
* regformats/i386/amd64-avx-linux.dat: Regenerated.
* regformats/i386/amd64-avx-mpx-linux.dat: Regenerated.
* regformats/i386/amd64-avx512-linux.dat: Regenerated.
* regformats/i386/amd64-linux.dat: Regenerated.
* regformats/i386/amd64-mpx-linux.dat: Regenerated.
* regformats/i386/x32-avx-linux.dat: Regenerated.
* regformats/i386/x32-avx512-linux.dat: Regenerated.
* regformats/i386/x32-linux.dat: Regenerated.
gdb/doc/ChangeLog:
* gdb.texinfo (i386 Features): Add system segment registers
as feature.
gdb/gdbserver/ChangeLog:
* linux-x86-low.c (x86_64_regmap): Add fs_base and gs_base
to the register table.
(x86_fill_gregset): Add support for old kernels for the
fs_base and gs_base system registers.
(x86_store_gregset): Likewise.
* configure.srv (srv_i386_64bit_xmlfiles): Add 64bit-segments.xml.
gdb/testsuite/ChangeLog:
* gdb.arch/amd64-gs_base.c: New file.
* gdb.arch/amd64-gs_base.exp: New file.
Change-Id: I2e0eeb93058a2320d4d3b045082643cfe4aff963
Signed-off-by: Walfred Tedeschi <walfred.tedeschi@intel.com>
The macros mentioned in the title were set only for GDB. In gdbserver they
were not set until now. To align the code in GDB and gdbserver these macros
are also added into gdbserver, enabling read and write of gs_base and fs_base
registers from the system in new and old kernels.
2017-01-27 Walfred Tedeschi <walfred.tedeschi@intel.com>
gdb/gdbserver/ChangeLog:
* configure.ac: Check if the fs_base and gs_base members of
`struct user_regs_struct' exist.
* config.in: Regenerated.
* configure: Likewise.
Before this patch, some functions would read the inferior memory with
(*the_target)->read_memory, which returns the raw memory, rather than the
shadowed memory.
This is wrong since these functions do not expect to read a breakpoint
instruction and can lead to invalid behavior.
Use of raw memory in get_next_pcs_read_memory_unsigned_integer for example
could lead to get_next_pc returning an invalid pc.
Here's how this would happen:
In non-stop:
the user issues:
thread 1
step&
thread 2
step&
thread 3
step&
In a similar way as non-stop-fair-events.exp (threads are looping).
GDBServer:
linux_resume is called
GDBServer has pending events,
threads are not resumed and single-step breakpoint for thread 1 not installed.
linux_wait_1 is called with a pending event on thread 2 at pc A
GDBServer handles the event and calls proceed_all_lwps
This calls proceed_one_lwp and installs single-step breakpoints on all
the threads that need one.
Now since thread 1 needs to install a single-step breakpoint and is at pc B
(different than thread 2), a step-over is not initiated and get_next_pc
is called to figure out the next instruction from pc B.
However it may just be that thread 3 as a single step breakpoint at pc
B. And thus get_next_pc fails.
This situation is tested with non-stop-fair-events.exp.
In other words, single-step breakpoints are installed in proceed_one_lwp
for each thread. GDBserver proceeds two threads for resume_step, as
requested by GDB, and the thread proceeded later may see the single-step
breakpoints installed for the thread proceeded just now.
Tested on gdbserver-native/-m{thumb,arm} no regressions.
gdb/gdbserver/ChangeLog:
* linux-aarch32-low.c (arm_breakpoint_kind_from_pc): Use
target_read_memory.
* linux-arm-low.c (get_next_pcs_read_memory_unsigned_integer): Likewise.
(get_next_pcs_syscall_next_pc): Likewise.
This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.
gdb/ChangeLog:
Update copyright year range in all GDB files.
Since we don't use suffix rules nor implicit rules in gdb, we can
disable them. The advantage is a slightly faster make [1].
Here are some numbers about the speedup. I ran this on my trusty old
Intel Q6600, so the time numbers are probably higher than what you'd get
on any recent hardware. I ran "make" in the gdb/ directory of an
already built repository (configured with --enable-targets=all). I
recorded the time of execution (average of 5). I then ran "make -d" and
recorded the number of printed lines, which gives a rough idea of the
number of operations done.
I compared the following configurations, to see the impact of both the
empty .SUFFIXES target and the empty pattern rules, as well as running
"make -r", which can be considered the "ideal" case.
A - baseline
B - baseline + .SUFFIXES
C - baseline + pattern rules
D - baseline + .SUFFIXES + pattern rules
E - baseline + make -r
config | time (s) | "make -d"
-----------------------------
A | 5.74 | 2396643
B | 1.19 | 298469
C | 2.81 | 1266573
D | 1.13 | 245489
E | 1.01 | 163914
We can see that the empty .SUFFIXES target has a bigger impact than the
empty pattern rules, but still it doesn't hurt to disable the implicit
pattern rules as well.
There are still some mentions of implicit rules I can't get rid of in
the "make -d" output. For example, it's trying to build .c files from
.w files:
Looking for an implicit rule for '/home/simark/src/binutils-gdb/gdb/infrun.c'.
Trying pattern rule with stem 'infrun'.
Trying implicit prerequisite '/home/simark/src/binutils-gdb/gdb/infrun.w'.
and trying to build Makefile.in from a bunch of extensions:
Looking for an implicit rule for 'Makefile.in'.
Trying pattern rule with stem 'Makefile.in'.
Trying implicit prerequisite 'Makefile.in.o'.
Trying pattern rule with stem 'Makefile.in'.
Trying implicit prerequisite 'Makefile.in.c'.
Trying pattern rule with stem 'Makefile.in'.
Trying implicit prerequisite 'Makefile.in.cc'.
... many more ...
If somebody knows how to disable them, we can do it, but at this point
the returns are minimal, so it is not that important.
I verified that both in-tree and out-of-tree builds work.
[1] Switching from explicit rules to pattern rules for files in
subdirectories actually made it slower, so this is kind of a way to
redeem myself. But it the end it's faster than it was previously,
so it was all worth it. :)
gdb/ChangeLog:
* disable-implicit-rules.mk: New file.
* Makefile.in: Include disable-implicit-rules.mk.
* data-directory/Makefile.in: Likewise.
* gnulib/Makefile.in: Likewise.
gdb/doc/ChangeLog:
* Makefile.in: Likewise.
gdb/gdbserver/ChangeLog:
* Makefile.in: Include disable-implicit-rules.mk.
gdb/testsuite/ChangeLog:
* Makefile.in: Include disable-implicit-rules.mk.
This patch fixes a few problems with GDB's time handling.
#1 - It avoids problems with gnulib's C++ namespace support
On MinGW, the struct timeval that should be passed to gnulib's
gettimeofday replacement is incompatible with libiberty's
timeval_sub/timeval_add. That's because gnulib also replaces "struct
timeval" with its own definition, while libiberty expects the
system's.
E.g., in code like this:
gettimeofday (&prompt_ended, NULL);
timeval_sub (&prompt_delta, &prompt_ended, &prompt_started);
timeval_add (&prompt_for_continue_wait_time,
&prompt_for_continue_wait_time, &prompt_delta);
That's currently handled in gdb by not using gnulib's gettimeofday at
all (see common/gdb_sys_time.h), but that #undef hack won't work with
if/when we enable gnulib's C++ namespace support, because that mode
adds compile time warnings for uses of ::gettimeofday, which are hard
errors with -Werror.
#2 - But there's an elephant in the room: gettimeofday is not monotonic...
We're using it to:
a) check how long functions take, for performance analysis
b) compute when in the future to fire events in the event-loop
c) print debug timestamps
But that's exactly what gettimeofday is NOT meant for. Straight from
the man page:
~~~
The time returned by gettimeofday() is affected by
discontinuous jumps in the system time (e.g., if the system
administrator manually changes the system time). If you need a
monotonically increasing clock, see clock_gettime(2).
~~~
std::chrono (part of the C++11 standard library) has a monotonic clock
exactly for such purposes (std::chrono::steady_clock). This commit
switches to use that instead of gettimeofday, fixing all the issues
mentioned above.
gdb/ChangeLog:
2016-11-23 Pedro Alves <palves@redhat.com>
* Makefile.in (SFILES): Add common/run-time-clock.c.
(HFILES_NO_SRCDIR): Add common/run-time-clock.h.
(COMMON_OBS): Add run-time-clock.o.
* common/run-time-clock.c, common/run-time-clock.h: New files.
* defs.h (struct timeval, print_transfer_performance): Delete
declarations.
* event-loop.c (struct gdb_timer) <when>: Now a
std::chrono::steady_clock::time_point.
(create_timer): use std::chrono::steady_clock instead of
gettimeofday. Use new instead of malloc.
(delete_timer): Use delete instead of xfree.
(duration_cast_timeval): New.
(update_wait_timeout): Use std::chrono::steady_clock instead of
gettimeofday.
* maint.c: Include <chrono> instead of "gdb_sys_time.h", <time.h>
and "timeval-utils.h".
(scoped_command_stats::~scoped_command_stats)
(scoped_command_stats::scoped_command_stats): Use
std::chrono::steady_clock instead of gettimeofday. Use
user_cpu_time_clock instead of get_run_time.
* maint.h: Include "run-time-clock.h" and <chrono>.
(scoped_command_stats): <m_start_cpu_time>: Now a
user_cpu_time_clock::time_point.
<m_start_wall_time>: Now a std::chrono::steady_clock::time_point.
* mi/mi-main.c: Include "run-time-clock.h" and <chrono> instead of
"gdb_sys_time.h" and <sys/resource.h>.
(rusage): Delete.
(mi_execute_command): Use new instead of XNEW.
(mi_load_progress): Use std::chrono::steady_clock instead of
gettimeofday.
(timestamp): Rewrite in terms of std::chrono::steady_clock,
user_cpu_time_clock and system_cpu_time_clock.
(timeval_diff): Delete.
(print_diff): Adjust to use std::chrono::steady_clock,
user_cpu_time_clock and system_cpu_time_clock.
* mi/mi-parse.h: Include "run-time-clock.h" and <chrono> instead
of "gdb_sys_time.h".
(struct mi_timestamp): Change fields types to
std::chrono::steady_clock::time_point, user_cpu_time_clock::time
and system_cpu_time_clock::time_point, instead of struct timeval.
* symfile.c: Include <chrono> instead of <time.h> and
"gdb_sys_time.h".
(struct time_range): New.
(generic_load): Use std::chrono::steady_clock instead of
gettimeofday.
(print_transfer_performance): Replace timeval parameters with a
std::chrono::steady_clock::duration parameter. Adjust.
* utils.c: Include <chrono> instead of "timeval-utils.h",
"gdb_sys_time.h", and <time.h>.
(prompt_for_continue_wait_time): Now a
std::chrono::steady_clock::duration.
(defaulted_query, prompt_for_continue): Use
std::chrono::steady_clock instead of
gettimeofday/timeval_sub/timeval_add.
(reset_prompt_for_continue_wait_time): Use
std::chrono::steady_clock::duration instead of struct timeval.
(get_prompt_for_continue_wait_time): Return a
std::chrono::steady_clock::duration instead of struct timeval.
(vfprintf_unfiltered): Use std::chrono::steady_clock instead of
gettimeofday. Use std::string. Use '.' instead of ':'.
* utils.h: Include <chrono>.
(get_prompt_for_continue_wait_time): Return a
std::chrono::steady_clock::duration instead of struct timeval.
gdb/gdbserver/ChangeLog:
2016-11-23 Pedro Alves <palves@redhat.com>
* debug.c: Include <chrono> instead of "gdb_sys_time.h".
(debug_vprintf): Use std::chrono::steady_clock instead of
gettimeofday. Use '.' instead of ':'.
* tracepoint.c: Include <chrono> instead of "gdb_sys_time.h".
(get_timestamp): Use std::chrono::steady_clock instead of
gettimeofday.
Mostly some whitespace changes to make things a bit more consistent.
gdb/ChangeLog:
* Makefile.in: Fix whitespace formatting.
gdb/gdbserver/ChangeLog:
* Makefile.in: Fix whitespace formatting.
I find the big file lists in the Makefiles a bit ugly and not very
practical. Since there are multiple filenames on each line (as much as
fits in 80 columns), it's not easy to add, remove or change a name in
the middle. As a result, we have a mix of long and short lines in no
particular order (ALL_TARGET_OBS is a good example).
I therefore suggest flattening the lists (one name per line) and keeping
them in alphabetical order. The diffs will be much clearer and merge
conflicts will be easier to resolve.
A nice (IMO) side-effect I observed is that the files are compiled
alphabetically by make, so it gives a rough idea of the progress of the
build.
I added a comment in gdb/Makefile.in to mention to keep the file lists
ordered, and gave the general guidelines on what order to respect. I
added a comment in other Makefiles which refers to gdb/Makefile.in, to
avoid duplication.
Running the patch through the buildbot found that gdb.base/default.exp
started to fail. The languages in the error message shown when typing
"set language" have changed order. We could probably improve gdb so
that it prints them in a stable order, regardless of the order of the
object list passed to the linked, but just fixing the test is easier for
now.
New in v2:
- Change ordering style, directories go at the end.
- Cleanup gdbserver's and data-directory's Makefile as well.
- Add comments at top of Makefiles about the ordering.
- Remove wrong trailing backslahes.
- Fix test gdb.base/default.exp.
gdb/ChangeLog:
* Makefile.in: Add comment about file lists ordering.
(SUBDIR_CLI_OBS, SUBDIR_CLI_SRCS, SUBDIR_MI_OBS, SUBDIR_MI_SRCS,
SUBDIR_TUI_OBS, SUBDIR_TUI_SRCS, SUBDIR_GCC_COMPILE_OBS,
SUBDIR_GCC_COMPILE_SRCS, SUBDIR_GUILE_OBS, SUBDIR_GUILE_SRCS,
SUBDIR_PYTHON_OBS, SUBDIR_PYTHON_SRCS, SUBDIR_GDBTK_OBS,
SUBDIR_GDBTK_SRCS, XMLFILES, REMOTE_OBS, ALL_64_TARGET_OBS,
ALL_TARGET_OBS, SFILES, HFILES_NO_SRCDIR, HFILES_WITH_SRCDIR,
COMMON_OBS, YYFILES, YYOBJ, generated_files, ALLDEPFILES):
Flatten list and order alphabetically.
* data-directory/Makefile.in: Add comment about file lists
ordering.
(GEN_SYSCALLS_FILES, PYTHON_FILE_LIST): Flatten list and order
alphabetically.
gdb/gdbserver/ChangeLog:
* Makefile.in (SFILES, OBS): Flatten list and order
alphabetically.
gdb/testsuite/ChangeLog:
* gdb.base/default.exp: Fix output of "set language".
As mentioned here [1], suffix rules are obsolete and have been
superseeded with pattern rules. People (myself included, before writing
this patch) are more likely to know what pattern rules are than suffix
rules.
AFAIK, .SUFFIXES targets are only used for those rules, and can be
removed as well.
New in v2:
- Replace rule in gdbserver/Makefile.in as well.
[1] https://www.gnu.org/software/make/manual/html_node/Suffix-Rules.html
gdb/ChangeLog:
* Makefile.in (.c.o): Replace rule with ...
(%.o: %.c): ... this one.
(.po.gmo): Replace rule with ...
(%.gmo: %.po): ... this one.
(.po.pox): Replace rule with ...
(%.pox: %.po): ... this one.
(.y.c): Replace rule with ...
(%.c: %.y): ... this one.
(.l.c): Replace rule with ...
(%.c: %.l): ... this one.
(.SUFFIXES): Remove all instances.
gdb/gdbserver/ChangeLog:
* Makefile.in (.c.o): Replace rule with ...
(%.o: %.c): ... this one.
Since GNU make is now required to build GDB, we can remove everything
that checks whether the current make implemention is the GNU one or
not. I simply removed the @GMAKE_TRUE@ prefixes and removed the whole
lines that were prefixed with @GMAKE_FALSE@.
I removed the code in the configure scripts that set those variables.
I also removed the following bits from the configure scripts:
AC_CHECK_PROGS(MAKE, make): GNU make already defines a MAKE variable
internally to be used when invoking Makefiles recursively. I don't see
this variable being used anywhere else (in scripts for example), so I
think it's safe for removal.
AC_PROG_MAKE_SET: This macro defines a SET_MAKE output variable, which
is meant to be used in Makefiles to define the MAKE variable when
using an implementation of make that doesn't already define it.
Since we are now requiring GNU make, we don't need it anymore.
Plus, I don't see SET_MAKE being used anywhere, so I don't think it
was actually doing anything...
gdb/ChangeLog:
* Makefile.in: Remove @GMAKE_TRUE@ prefixes and removes lines
prefixed with @GMAKE_FALSE@. Update comment related to non-GNU
make.
* configure.ac: Remove checks for the make program.
* configure: Re-generate.
gdb/gdbserver/ChangeLog:
* Makefile.in: Remove @GMAKE_TRUE@ prefixes and removes lines
prefixed with @GMAKE_FALSE@. Update comment related to non-GNU
make.
* configure.ac: Remove checks for the make program.
* configure: Re-generate.
gdb/testsuite/ChangeLog:
* Makefile.in: Remove @GMAKE_TRUE@ prefixes and removes lines
prefixed with @GMAKE_FALSE@. Update comment related to non-GNU
make.
* configure.ac: Remove checks for the make program.
* configure: Re-generate.
Use AX_CXX_COMPILE_STDCXX to detect if the compiler supports C++11,
and if -std=xxx switches are necessary to enable C++11.
We need to tweak AX_CXX_COMPILE_STDCXX a bit though. Pristine
upstream AX_CXX_COMPILE_STDCXX appends -std=gnu++11 to CXX directly.
That doesn't work for us, because the top level Makefile passes CXX
down to subdirs, and that overrides whatever gdb/Makefile may set CXX
to. The result would be that a make invocation from the build/gdb/
directory would use "g++ -std=gnu++11" as expected, while a make
invocation at the top level would not.
So instead of having AX_CXX_COMPILE_STDCXX set CXX directly, tweak it
to AC_SUBST a separate variable -- CXX_DIALECT -- and use '$(CXX)
(CXX_DIALECT)' to compile/link.
Confirmed that this enables C++11 starting with gcc 4.8, the first gcc
release with full C++11 support.
Also confirmed that configure errors out gracefully with older GCC
releases:
checking whether /opt/gcc-4.7/bin/g++ supports C++11 features by default... no
checking whether /opt/gcc-4.7/bin/g++ supports C++11 features with -std=gnu++11... no
checking whether /opt/gcc-4.7/bin/g++ supports C++11 features with -std=gnu++0x... no
checking whether /opt/gcc-4.7/bin/g++ supports C++11 features with -std=c++11... no
checking whether /opt/gcc-4.7/bin/g++ supports C++11 features with -std=c++0x... no
checking whether /opt/gcc-4.7/bin/g++ supports C++11 features with +std=c++11... no
checking whether /opt/gcc-4.7/bin/g++ supports C++11 features with -h std=c++11... no
configure: error: *** A compiler with support for C++11 language features is required.
Makefile:9451: recipe for target 'configure-gdb' failed
make[1]: *** [configure-gdb] Error 1
make[1]: Leaving directory '/home/pedro/brno/pedro/gdb/mygit/cxx-convertion/build-gcc-4.7'
If we need to revert back to making C++11 optional, all that's
necessary is to change the "mandatory" to "optional" in configure.ac
and regenerate configure (both gdb and gdbserver).
gdb/ChangeLog:
2016-10-28 Pedro Alves <palves@redhat.com>
* Makefile.in (CXX_DIALECT): Get from configure.
(COMPILE.pre, CC_LD): Append $(CXX_DIALECT).
(FLAGS_TO_PASS): Pass CXX_DIALECT.
* acinclude.m4: Include ax_cxx_compile_stdcxx.m4.
* ax_cxx_compile_stdcxx.m4: Add FSF copyright header. Set and
AC_SUBST CXX_DIALECT instead of changing CXX/CXXCPP.
* configure.ac: Call AX_CXX_COMPILE_STDCXX.
* config.in: Regenerate.
* configure: Regenerate.
gdb/gdbserver/ChangeLog:
2016-10-28 Pedro Alves <palves@redhat.com>
* Makefile.in (CXX_DIALECT): Get from configure.
(COMPILE.pre, CC_LD): Append $(CXX_DIALECT).
* acinclude.m4: Include ../ax_cxx_compile_stdcxx.m4.
* configure.ac: Call AX_CXX_COMPILE_STDCXX.
* config.in: Regenerate.
* configure: Regenerate.
If the target can do software single step, it can do range
stepping.
gdb/gdbserver:
2016-10-27 Yao Qi <yao.qi@linaro.org>
* linux-low.c (linux_supports_agent): Return true if
can_software_single_step return true.
Nowadays, we select events to be reported to GDB in random, however
that is not enough when many GDBserver internal events (not reported
to GDB) are generated.
GDBserver pulls all events out of kernel via waitpid, and leave them
pending. When goes through threads which have pending events,
GDBserver uses find_inferior to find the first thread which has
pending event, and consumes it. Note that find_inferior always
iterate threads in a fixed order. If multiple threads keep hitting
GDBserver breakpoints, range stepping with single-step breakpoint for
example, threads in the head of the thread list are more likely to be
processed and threads in the tail are starved. This causes some timeout
fails in gdb.threads/non-stop-fair-events.exp when range stepping is
enabled on arm-linux.
This patch fixes this issue by randomly selecting pending events. It
adds a new function find_inferior_in_random, which iterates threads
which have pending events randomly.
gdb/gdbserver:
2016-10-27 Yao Qi <yao.qi@linaro.org>
* inferiors.c (find_inferior_in_random): New function.
* inferiors.h (find_inferior_in_random): Declare.
* linux-low.c (linux_wait_for_event_filtered): Call
find_inferior_in_random instead of find_inferior.
This patch removes single-step breakpoints if the event is only
GDBserver internal, IOW, isn't reported back to GDB.
gdb/gdbserver:
2016-10-27 Yao Qi <yao.qi@linaro.org>
* linux-low.c (linux_wait_1): If single-step breakpoints are
inserted, remove them.
Currently GDB never sends more than one action per vCont packet, when
connected in non-stop mode. A follow up patch will change that, and
it exposed a gdbserver problem with the vCont handling.
For example, this in non-stop mode:
=> vCont;s:p1.1;c
<= OK
Should be equivalent to:
=> vCont;s:p1.1
<= OK
=> vCont;c
<= OK
But gdbserver currently doesn't handle this. In the latter case,
"vCont;c" makes gdbserver clobber the previous step request. This
patch fixes that.
Note the server side must ignore resume actions for the thread that
has a pending %Stopped notification (and any other threads with events
pending), until GDB acks the notification with vStopped. Otherwise,
e.g., the following case is mishandled:
#1 => g (or any other packet)
#2 <= [registers]
#3 <= %Stopped T05 thread:p1.2
#4 => vCont s:p1.1;c
#5 <= OK
Above, the server must not resume thread p1.2 when it processes the
vCont. GDB can't know that p1.2 stopped until it acks the %Stopped
notification. (Otherwise it wouldn't send a default "c" action.)
(The vCont documentation already specifies this.)
Finally, special care must also be given to handling fork/vfork
events. A (v)fork event actually tells us that two processes stopped
-- the parent and the child. Until we follow the fork, we must not
resume the child. Therefore, if we have a pending fork follow, we
must not send a global wildcard resume action (vCont;c). We can still
send process-wide wildcards though.
(The comments above will be added as code comments to gdb in a follow
up patch.)
gdb/gdbserver/ChangeLog:
2016-10-26 Pedro Alves <palves@redhat.com>
* linux-low.c (handle_extended_wait): Link parent/child fork
threads.
(linux_wait_1): Unlink them.
(linux_set_resume_request): Ignore resume requests for
already-resumed and unhandled fork child threads.
* linux-low.h (struct lwp_info) <fork_relative>: New field.
* server.c (in_queued_stop_replies_ptid, in_queued_stop_replies):
New functions.
(handle_v_requests) <vCont>: Don't call require_running.
* server.h (in_queued_stop_replies): New declaration.
I got the following warning if I build GDBserver for aarch64_be-linux-gnu,
git/gdb/gdbserver/linux-aarch64-low.c:1539:39: error: invalid conversion from 'void*' to 'uint32_t* {aka unsigned int*}' [-fpermissive]
uint32_t *le_buf = xmalloc (byte_len);
^
The patch is to fix the warning.
gdb/gdbserver:
2016-10-24 Yao Qi <yao.qi@linaro.org>
PR server/20733
* linux-aarch64-low.c (append_insns): Cast the return value to
'uint32_t *'.
This patch shares "enum arm_breakpoint_kinds", and use ARM_BP_KIND_THUMB2
in GDB.
gdb:
2016-10-10 Yao Qi <yao.qi@linaro.org>
* arch/arm.h (enum arm_breakpoint_kinds): New.
* arm-tdep.c (arm_remote_breakpoint_from_pc): Use
ARM_BP_KIND_THUMB2.
gdb/gdbserver:
2016-10-10 Yao Qi <yao.qi@linaro.org>
* linux-aarch32-low.c (enum arm_breakpoint_kinds): Remove.
This simple commit consolidates the API of
target_supports_multi_process. Since both GDB and gdbserver use the
same function prototype, all that was needed was to move create this
prototype on gdb/target/target.h and turn the macros declared on
gdb/{,gdbserver/}target.h into actual functions.
Regtested (clean pass) on the BuildBot.
gdb/ChangeLog:
2016-10-06 Sergio Durigan Junior <sergiodj@redhat.com>
* target.c (target_supports_multi_process): New function, moved
from...
* target.h (target_supports_multi_process): ... here. Remove
macro.
* target/target.h (target_supports_multi_process): New prototype.
gdb/gdbserver/ChangeLog:
2016-10-06 Sergio Durigan Junior <sergiodj@redhat.com>
* target.c (target_supports_multi_process): New function, moved
from...
* target.h (target_supports_multi_process): ... here. Remove
macro.
handle_tracepoint_bkpts has two parallel "if"s. This changes the
second one to check ipa_error_tracepoint, which seems to be what was
intended.
2016-10-05 Tom Tromey <tom@tromey.com>
PR remote/20655:
* tracepoint.c (handle_tracepoint_bkpts): Check
ipa_error_tracepoint, not ipa_stopping_tracepoint.
0a69eedb (Clean up the XML files for ARM) breaks the GDBserver build
on aarch64 because some arm-*.xml files can't be found.
This patch is to fix the build failure.
gdb/gdbserver:
2016-10-05 Yao Qi <yao.qi@linaro.org>
* configure.srv: Update the path of arm-*.xml files.
This patch is move features/arm-*.xml to features/arm/, and it is based
on Terry's patch posted here
https://sourceware.org/ml/gdb-patches/2014-06/msg00794.html
One comment to Terry's patch is about losing "arm" prefix, and the new
patch fixes this problem.
gdb:
2016-10-05 Terry Guo <terry.guo@arm.com>
Yao Qi <yao.qi@linaro.org>
* arm-tdep.c: Adjust includes.
* features/Makefile (WHICH): Add "arm/" directory to arm
target descriptions.
(XMLTOC): Likewise.
(arm/arm-with-iwmmxt.dat): Adjust the path for
dependencies.
* features/arm-core.xml: Moved to ...
* features/arm/arm-core.xml: ... it.
* features/arm-fpa.xml: Moved to ...
* features/arm/arm-fpa.xml: ... it.
* features/arm-m-profile.xml: Moved to ...
* features/arm/arm-m-profile.xm: ... it.
* features/arm-vfpv2.xml: Moved to ...
* features/arm/arm-vfpv2.xm: ... it.
* features/arm-vfpv3.xml: Moved to ...
* features/arm/arm-vfpv3.xml: ... it.
* features/arm-with-iwmmxt.c: Moved to ...
* features/arm/arm-with-iwmmxt.c: ... it.
* features/arm-with-iwmmxt.xml: Moved to ...
* features/arm/arm-with-iwmmxt.xml: ... it.
* features/arm-with-m-fpa-layout.c: Moved to ...
* features/arm/arm-with-m-fpa-layout.c: ... it.
* features/arm-with-m-fpa-layout.xml: Moved to ...
* features/arm/arm-with-m-fpa-layout.xml: ... it.
* features/arm-with-m-vfp-d16.c: Moved to ...
* features/arm/arm-with-m-vfp-d16.c: ... it.
* features/arm-with-m-vfp-d16.xml: Moved to ...
* features/arm/arm-with-m-vfp-d16.xml: ... it.
* features/arm-with-m.c: Moved to ...
* features/arm/arm-with-m.c: ... it.
* features/arm-with-m.xml: Moved to ...
* features/arm/arm-with-m.xm: ... it.
* features/arm-with-neon.c: Moved to ...
* features/arm/arm-with-neon.c: ... it.
* features/arm-with-neon.xml: Moved to ...
* features/arm/arm-with-neon.xml: ... it.
* features/arm-with-vfpv2.c: Moved to ...
* features/arm/arm-with-vfpv2.c: ... it.
* features/arm-with-vfpv2.xml: Moved to ...
* features/arm/arm-with-vfpv2.xml: ... it.
* features/arm-with-vfpv3.c: Moved to ...
* features/arm/arm-with-vfpv3.c: ... it.
* features/arm-with-vfpv3.xml: Moved to ...
* features/arm/arm-with-vfpv3.xml: ... it.
* features/xscale-iwmmxt.xml: Moved to ...
* features/arm/xscale-iwmmxt.xml: ... it.
gdb/gdbserver:
2016-10-05 Terry Guo <terry.guo@arm.com>
Yao Qi <yao.qi@linaro.org>
* Makefile.in: Adjust the path of rules.
* configure.srv: Update the path of xml files.
* regformats/arm-with-iwmmxt.dat: Regenerated.
* regformats/arm-with-neon.dat: Likewise.
* regformats/arm-with-vfpv2.dat: Likewise.
* regformats/arm-with-vfpv3.dat Likewise.
Commit 049a8570 (Use target_continue{,_no_signal} instead of target_resume)
replaces the code stopping lwp with target_continue_no_signal in
target_stop_and_wait, like this,
- resume_info.thread = ptid;
- resume_info.kind = resume_stop;
- resume_info.sig = GDB_SIGNAL_0;
- (*the_target->resume) (&resume_info, 1);
+ target_continue_no_signal (ptid);
the replacement is not equivalent, and it causes PR 20627. This patch
is just to revert that change.
Regression testing it on x86_64-linux.
gdb/gdbserver:
2016-09-30 Yao Qi <yao.qi@linaro.org>
PR gdbserver/20627
* target.c (target_stop_and_wait): Don't call
target_continue_no_signal, use resume_stop instead.
When I read the GDBserver debug message, I find the "entering" of
linux_wait_1 doesn't match the "existing" of linux_wait_1. Looks
we don't call debug_exit somewhere in linux_wait_1 on return.
gdb/gdbserver:
2016-09-26 Yao Qi <yao.qi@linaro.org>
* linux-low.c (linux_wait_1): Call debug_exit.
If xmalloc fails allocating memory, usually because something tried a
huge allocation, like xmalloc(-1) or some such, GDB asks the user what
to do:
.../src/gdb/utils.c:1079: internal-error: virtual memory exhausted.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n)
If the user says "n", that throws a QUIT exception, which is caught by
one of the multiple CATCH(RETURN_MASK_ALL) blocks somewhere up the
stack.
The default implementations of operator new / operator new[] call
malloc directly, and on memory allocation failure throw
std::bad_alloc. Currently, if that happens, since nothing catches it,
the exception escapes out of main, and GDB aborts from unhandled
exception.
This patch replaces the default operator new variants with versions
that, just like xmalloc:
#1 - Raise an internal-error on memory allocation failure.
#2 - Throw a QUIT gdb_exception, so that the exact same CATCH blocks
continue handling memory allocation problems.
A minor complication of #2 is that operator new can _only_ throw
std::bad_alloc, or something that extends it:
void* operator new (std::size_t size) throw (std::bad_alloc);
That means that if we let a gdb QUIT exception escape from within
operator new, the C++ runtime aborts due to unexpected exception
thrown.
So to bridge the gap, this patch adds a new gdb_quit_bad_alloc
exception type that inherits both std::bad_alloc and gdb_exception,
and throws _that_.
If we decide that we should be catching memory allocation errors in
fewer places than all the places we currently catch them (everywhere
we use RETURN_MASK_ALL currently), then we could change operator new
to throw plain std::bad_alloc then. But I'm considering such a change
as separate matter from this one -- it'd make sense to do the same to
xmalloc at the same time, for instance.
Meanwhile, this allows using new/new[] instead of xmalloc/XNEW/etc.
without losing the "virtual memory exhausted" internal-error
safeguard.
Tested on x86_64 Fedora 23.
gdb/ChangeLog:
2016-09-23 Pedro Alves <palves@redhat.com>
* Makefile.in (SFILES): Add common/new-op.c.
(COMMON_OBS): Add common/new-op.o.
(new-op.o): New rule.
* common/common-exceptions.h: Include <new>.
(struct gdb_quit_bad_alloc): New type.
* common/new-op.c: New file.
gdb/gdbserver/ChangeLog:
2016-09-23 Pedro Alves <palves@redhat.com>
* Makefile.in (SFILES): Add common/new-op.c.
(OBS): Add common/new-op.o.
(new-op.o): New rule.
Sergio Durigan Junior