callback.h:struct host_callback_struct compilation error on Windows hosts.

On Windows, a recent gnulib update imported the lstat module, and
this caused a remote-sim.c build failure in struct host_callback_struct:

    In file included from /[...]/gdb/remote-sim.c:34:0:
    /[...]/gdb/../include/gdb/callback.h:93:9: error: duplicate member '_stati64'
       int (*lstat) (host_callback *, const char *, struct stat *);
             ^
What happens it that gnulib's stat.h makes the following defines:

     /* Large File Support on native Windows.  */
     #if 1
     # define stat _stati64
     #endif

and then:

    #if 1
    # if ! 0
    /* mingw does not support symlinks, therefore it does not have lstat.  But
       without links, stat does just fine.  */
    #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
    #   define lstat stat
    #  endif

So, the following fields in struct host_callback_struct...

      int (*stat) (host_callback *, const char *, struct stat *);
      int (*fstat) (host_callback *, int, struct stat *);
      int (*lstat) (host_callback *, const char *, struct stat *);

... get translated to...

      int (*_stati64) (host_callback *, const char *, struct _stati64 *);
      int (*_fstati64) (host_callback *, int, struct _stati64 *);
      int (*_stati64) (host_callback *, const char *, struct _stati64 *);

... which causes two fields to have the same name.

This patch fixes the issue by renaming the stat-related fields
by adding a "to_" prefix, similar to what is done in GDB's
target_ops vector.

include/gdb/ChangeLog:

	* callback.h (struct host_callback_struct) <to_stat>: Renamed
	from "stat".
	<to_fstat>: Renamed from "fstat".
	<to_lstat>: Renamed from "lstat".

sim/common/ChangeLog:

	* sim-io.c (sim_io_stat, sim_io_fstat): Adjust calls to "stat"
	and "fstat" callbacks by calls to "to_stat" and "to_fstat" (resp)
	callbacks following renaming in callback.h.
	* syscall.c (cb_syscall): Likewise.  Adjust calls to "lstat"
	callback by call to "to_lstat" callback

sim/cris/ChangeLog:

	* traps.c (cris_break_13_handler): Adjust call to "fstat" callback
	by call to "to_fstat" following renaming in callback.h.

sim/h8300/ChangeLog:

	* compile.c (sim_resume):  Adjust calls to "stat" and "fstat"
	callbacks by calls to "to_stat" and "to_fstat" (resp) callbacks
	following renaming in callback.h.
Fix make_cleanup_dtor signature to match declaration

The definition does not use the typedef for the dtor function pointer
type that the declaration uses.  It's a cosmetic-only change.

ChangeLog:

	* common/cleanups.c (make_cleanup_dtor): Use typedef for dtor
	type.
Use core regset iterators on Sparc Solaris

Remove native-only core file handling on Sparc Solaris.  Instead,
enable the sparc target generic core regset logic on Solaris by
providing appropriate register offset maps.

Thanks to Joel Brobecker for testing!

gdb/
	* config/sparc/sol2.mh (NATDEPFILES): Remove core-regset.o.
	* sparc-sol2-tdep.c: Include "regset.h".
	(sparc32_sol2_supply_core_gregset): New function.
	(sparc32_sol2_collect_core_gregset): Likewise.
	(sparc32_sol2_supply_core_fpregset): Likewise.
	(sparc32_sol2_collect_core_fpregset): Likewise.
	(sparc32_sol2_gregset, sparc32_sol2_fpregset): New variables.
	(sparc32_sol2_init_abi): Set tdep->gregset/sizeof_gregset and
	tdep->fpregset/sizeof_fpregset.
	* sparc64-sol2-tdep.c: Include "regset.h".
	(sparc64_sol2_supply_core_gregset): New function.
	(sparc64_sol2_collect_core_gregset): Likewise.
	(sparc64_sol2_supply_core_fpregset): Likewise.
	(sparc64_sol2_collect_core_fpregset): Likewise.
	(sparc64_sol2_gregset, sparc64_sol2_fpregset): New variables.
	(sparc64_sol2_init_abi): Set tdep->gregset/sizeof_gregset and
	tdep->fpregset/sizeof_fpregset.
powerpc gold, fix pr17566

Code stolen from arm.cc.

	PR 17566
	* powerpc.cc (Target_powerpc::Scan::local): Use add_local_section
	when adding dynamic relocations against section symbols.
Reformat elf_x86_64_create_dynamic_sections

	* elf64-x86-64.c (elf_x86_64_create_dynamic_sections): Reformat.
Replace calls to abort (in readelf) with informative error messages.

	PR binutils/17531
	* readelf.c (get_machine_flags): Replace call to abort with a
	warning message and a return value.
	(get_elf_section_flags): Likewise.
	(get_symbol_visibility): Likewise.
	(get_ia64_symbol_other): Likewise.
	(get_ia64_symbol_other): Likewise.
	(is_32bit_abs_reloc): Likewise.
	(apply_relocations): Likewise.
	(display_arm_attribute): Likewise.
Replace copyreloc-main.c with copyreloc-main.S

	* ld-x86-64/copyreloc-main.c: Removed.
	* ld-x86-64/copyreloc-main.S: New.
	* ld-x86-64/x86-64.exp: Replace copyreloc-main.c with
	copyreloc-main.S.
Compile pie_copyrelocs_test.cc with -fno-exceptions -fno-asynchronous-unwind-tables

	PR gold/17675
	* testsuite/Makefile.am (pie_copyrelocs_test_CXXFLAGS): New.
	* testsuite/Makefile.in: Regenerated.
Fix memory access problems exposed by fuzzed binaries.

	PR binutils/17512
	* objdump.c (free_debug_section): Reset the compress_status as
	well.

	* compress.c (bfd_get_full_section_contents): Fail if there are no
	section contents available when the compress_status is
	COMPRESS_SECTION_DONE.
	* libbfd.c (bfd_malloc): Refuse to allocate a negative size.
	(bfd_malloc2): Use bfd_malloc.
	(bfd_realloc): Refuse to reallocate a negative size.
	(bfd_realloc2): Use bfd_realloc.
	(bfd_realloc_or_free): Use bfd_realloc.
	(bfd_zmalloc): Use bfd_malloc.
	(bfd_zmalloc): Use bfd_malloc2.
	* opncls.c (bfd_alloc): Refuse to allocate a negative size.
MIPS: Add support for microMIPS Linux signal trampolines

The necessity for this change has been revealed in the course of
investigation related to proposed changes in the treatment of the ISA
bit encoded in function symbols on the MIPS target.  This change adds
support for Linux signal trampolines encoded with the microMIPS
instruction set.  Such trampolines are used by the Linux kernel if
compiled as a microMIPS binary (even if the binary run/debugged itself
contains no microMIPS code at all).

To see if we need to check whether the execution mode selected matches
the given trampoline I have checked what the bit patterns of all the
trampoline sequences decode to in the opposite instruction set.  This
produced useless or at least unusual code in most cases, for example:

microMIPS/EB, o32 sigreturn, decoded as MIPS code:
	30401017 	andi	zero,v0,0x1017
	00008b7c 	dsll32	s1,zero,0xd

MIPS/EL, o32 sigreturn, decoded as microMIPS code:
	1017 2402 	addi	zero,s7,9218
	000c 0000 	sll	zero,t0,0x0

However in some corner cases reasonable code can mimic a trampoline, for
example:

MIPS/EB, n32 rt_sigreturn, decoded as microMIPS code:
	2402      	sll	s0,s0,1
	1843 0000 	sb	v0,0(v1)
	000c 0f3c 	jr	t0

-- here the first instruction is a 16-bit one, making things nastier
even as there are some other microMIPS instructions whose first 16-bit
halfword is 0x000c and therefore matches this whole trampoline pattern.

To overcome this problem I have decided the signal trampoline unwinder
has to ask the platform backend whether it can apply a given trampoline
pattern to the code location being concerned or not.  Anticipating the
acceptance of the ISA bit proposal I decided the handler not to merely
be a predicate, but also to be able to provide an adjusted PC if
required.  I decided that returning zero will mean that the trampoline
pattern is not applicable and any other value is the adjusted PC to use;
a handler may return the value requested if the trampoline pattern and
the PC requested as-is are both accepted.

This changes the semantics of the trampoline unwinder a bit in that the
zero PC now has a special value.  I think this should be safe as a NULL
pointer is generally supposed to be invalid.

	* tramp-frame.h (tramp_frame): Add `validate' member.
	* tramp-frame.c (tramp_frame_start): Validate trampoline before
	scanning.
	* mips-linux-tdep.c (MICROMIPS_INST_LI_V0): New macro.
	(MICROMIPS_INST_POOL32A, MICROMIPS_INST_SYSCALL): Likewise.
	(mips_linux_o32_sigframe): Initialize `validate' member.
	(mips_linux_o32_rt_sigframe): Likewise.
	(mips_linux_n32_rt_sigframe): Likewise.
	(mips_linux_n64_rt_sigframe): Likewise.
	(micromips_linux_o32_sigframe): New variable.
	(micromips_linux_o32_rt_sigframe): Likewise.
	(micromips_linux_n32_rt_sigframe): Likewise.
	(micromips_linux_n64_rt_sigframe): Likewise.
	(mips_linux_o32_sigframe_init): Handle microMIPS trampolines.
	(mips_linux_n32n64_sigframe_init): Likewise.
	(mips_linux_sigframe_validate): New function.
	(micromips_linux_sigframe_validate): Likewise.
	(mips_linux_init_abi): Install microMIPS trampoline unwinders.
powerpc gold, work around pr17670

pr17670 is about an assert triggering on a branch to an undefined
weak symbol, the symbol being undefined due to dropping its comdat
group section.  (Well sort of.  The symbol is actually defined in
an .opd section which isn't part of the group, but the code section
the opd entry points at is dropped.)  So don't assert.
Also, don't make long branch stubs to such symbols, and arrange to
have target-reloc.h code warn when applying relocs that use the sym.

	PR 17670
	* symtab.cc (Symbol::set_undefined): Remove assertion.
	* powerpc.cc (Target_powerpc::symval_for_branch): Don't assert
	on symbols defined in discarded sections, instead return false.
	Rearrange params, update all callers.
	(Target_powerpc::Branch_info::make_stub): Don't make stubs for
	branches to syms in discarded sections.
	(Global_symbol_visitor_opd::operator()): Set discarded opd syms
	undefined and flag as discarded.
	(Target_powerpc::Relocate::relocate): Localize variable.
Automatic date update in version.in
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.