Assuming displaced stepping is enabled, and a breakpoint is set in the
memory region of the scratch pad, things break. One of two cases can
happen:
#1 - The breakpoint wasn't inserted yet (all threads were stopped), so
after setting up the displaced stepping scratch pad with the
adjusted copy of the instruction we're trying to single-step, we
insert the breakpoint, which corrupts the scratch pad, and the
inferior executes the wrong instruction. (Example below.)
This is clearly unacceptable.
#2 - The breakpoint was already inserted, so setting up the displaced
stepping scratch pad overwrites the breakpoint. This is OK in
the sense that we already assume that no thread is going to
executes the code in the scratch pad range (after initial
startup) anyway.
This commit addresses both cases by simply punting on displaced
stepping if we have a breakpoint in the scratch pad range.
The #1 case above explains a few regressions exposed by the AS/NS
series on x86:
Running ./gdb.dwarf2/callframecfa.exp ...
FAIL: gdb.dwarf2/callframecfa.exp: set display for call-frame-cfa
FAIL: gdb.dwarf2/callframecfa.exp: step 1 for call-frame-cfa
FAIL: gdb.dwarf2/callframecfa.exp: step 2 for call-frame-cfa
FAIL: gdb.dwarf2/callframecfa.exp: step 3 for call-frame-cfa
FAIL: gdb.dwarf2/callframecfa.exp: step 4 for call-frame-cfa
Running ./gdb.dwarf2/typeddwarf.exp ...
FAIL: gdb.dwarf2/typeddwarf.exp: continue to breakpoint: continue to typeddwarf.c:53
FAIL: gdb.dwarf2/typeddwarf.exp: check value of x at typeddwarf.c:53
FAIL: gdb.dwarf2/typeddwarf.exp: check value of y at typeddwarf.c:53
FAIL: gdb.dwarf2/typeddwarf.exp: check value of z at typeddwarf.c:53
FAIL: gdb.dwarf2/typeddwarf.exp: continue to breakpoint: continue to typeddwarf.c:73
FAIL: gdb.dwarf2/typeddwarf.exp: check value of w at typeddwarf.c:73
FAIL: gdb.dwarf2/typeddwarf.exp: check value of x at typeddwarf.c:73
FAIL: gdb.dwarf2/typeddwarf.exp: check value of y at typeddwarf.c:73
FAIL: gdb.dwarf2/typeddwarf.exp: check value of z at typeddwarf.c:73
Enabling "maint set target-non-stop on" implies displaced stepping
enabled as well, and it's the latter that's to blame here. We can see
the same failures with "maint set target-non-stop off + set displaced
on".
Diffing (good/bad) gdb.log for callframecfa.exp shows:
@@ -99,29 +99,29 @@ Breakpoint 2 at 0x80481b0: file q.c, lin
continue
Continuing.
-Breakpoint 2, func (arg=77) at q.c:2
+Breakpoint 2, func (arg=52301) at q.c:2
2 in q.c
(gdb) PASS: gdb.dwarf2/callframecfa.exp: continue to breakpoint: continue to breakpoint for call-frame-cfa
display arg
-1: arg = 77
-(gdb) PASS: gdb.dwarf2/callframecfa.exp: set display for call-frame-cfa
+1: arg = 52301
+(gdb) FAIL: gdb.dwarf2/callframecfa.exp: set display for call-frame-cfa
The problem is here, when setting up the func call:
Breakpoint 1, main (argc=-13345, argv=0x0) at q.c:7
7 in q.c
(gdb) disassemble
Dump of assembler code for function main:
0x080481bb <+0>: push %ebp
0x080481bc <+1>: mov %esp,%ebp
0x080481be <+3>: sub $0x4,%esp
=> 0x080481c1 <+6>: movl $0x4d,(%esp)
0x080481c8 <+13>: call 0x80481b0 <func>
0x080481cd <+18>: leave
0x080481ce <+19>: ret
End of assembler dump.
(gdb) disassemble /r
Dump of assembler code for function main:
0x080481bb <+0>: 55 push %ebp
0x080481bc <+1>: 89 e5 mov %esp,%ebp
0x080481be <+3>: 83 ec 04 sub $0x4,%esp
=> 0x080481c1 <+6>: c7 04 24 4d 00 00 00 movl $0x4d,(%esp)
0x080481c8 <+13>: e8 e3 ff ff ff call 0x80481b0 <func>
0x080481cd <+18>: c9 leave
0x080481ce <+19>: c3 ret
End of assembler dump.
Note the breakpoint at main is set at 0x080481c1. Right at the
instruction that sets up func's argument. Executing that instruction
should write 0x4d to the address pointed at by $esp. However, if we
stepi, the program manages to write 52301/0xcc4d there instead (0xcc
is int3, the x86 breakpoint instruction), because the breakpoint
address is 4 bytes inside the scratch pad location, which is
0x080481bd:
(gdb) p 0x080481c1 - 0x080481bd
$1 = 4
IOW, instead of executing:
"c7 04 24 4d 00 00 00" [ movl $0x4d,(%esp) ]
the inferior executes:
"c7 04 24 4d cc 00 00" [ movl $0xcc4d,(%esp) ]
gdb/ChangeLog:
2015-10-30 Pedro Alves <palves@redhat.com>
* breakpoint.c (breakpoint_in_range_p)
(breakpoint_location_address_range_overlap): New functions.
* breakpoint.h (breakpoint_in_range_p): New declaration.
* infrun.c (displaced_step_prepare_throw): If there's a breakpoint
in the scratch pad range, don't displaced step.
Nowadays, test gdb.threads/wp-replication.exp uses a while loop to
repeatedly insert HW watchpoint, resume and check no error message
coming out, in order to count HW watchpoints There are some
drawbacks in this way,
- the loop could be endless. I think this is use to making trouble
to S/390, since we had such comment
# Some targets (like S/390) behave as though supporting
# unlimited hardware watchpoints. In this case we just take a
# safe exit out of the loop.
I hit this today too because a GDB internal error is triggered
on "continue" in the loop, and $done is 0 invariantly, so the loop
can't end.
- the code counting hardware watchpoint is too complicated. We can
use "set breakpoint always-inserted on" to get the result of inserting
HW watchpoint without resuming the inferior. In this way,
watch_count_done and empty_cycle in c file is no longer needed.
In this patch, I change to use "set breakpoint always-inserted on" trick,
and only iterate $NR_THREADS times, to count the HW watchpoint. In this
way, the loop can't be endless, and GDB doesn't need to resume the inferior.
gdb/testsuite:
2015-10-30 Yao Qi <yao.qi@linaro.org>
* gdb.threads/wp-replication.c (watch_count_done): Remove.
(empty_cycle): Remove.
(main): Don't call empty_cycle. Don't use watch_count_done.
* gdb.threads/wp-replication.exp: Don't set breakpoint on
empty_cycle. Rewrite the code counting HW watchpoints.
60 bytes is the size of glibc's struct termios, the one used by kernel is
36 bytes long.
gdb/ChangeLog:
* aarch64-linux-tdep.c (aarch64_linux_init_abi): Fix size_termios.
* amd64-linux-tdep.c (amd64_linux_init_abi): Fix size_termios.
(amd64_x32_linux_init_abi): Fix size_termios.
We have to use extract_unsigned_integer to read paramaters structure - target
pointers can have different endianness and size.
gdb/ChangeLog:
* linux-record.c (record_linux_system_call): Fix old_select.
Memory size for getgroups16 needs to be multiplied by entry count, and only
needs recording if the pointer is non-NULL. setgroups16, on the other hand,
doesn't write to user memory and doesn't need special handling at all.
gdb/ChangeLog:
* linux-record.c (record_linux_system_call): Fix [gs]etgroups16.
The code failed to account for padding between the int and subsequent
pointer present on 64-bit architectures.
gdb/ChangeLog:
* linux-record.c (record_linux_msghdr): Fix msg_namelen handling.
getdents buffer size is given in bytes, not dirent entries (which have
variable size anyway). We don't need size_dirent and size_dirent64 for
this reason.
readdir, on the other hand, needs size of old_linux_dirent, which is
a somewhat different structure. Accordingly, rename size_dirent
to size_old_dirent.
gdb/ChangeLog:
* aarch64-linux-tdep.c (aarch64_linux_init_abi): Remove
size_dirent{,64}, add size_old_dirent.
* amd64-linux-tdep.c (amd64_linux_init_abi): Remove size_dirent{,64},
add size_old_dirent.
(amd64_x32_linux_init_abi): Remove size_dirent{,64}, add
size_old_dirent.
* arm-linux-tdep.c (arm_linux_init_abi): Remove size_dirent{,64},
add size_old_dirent.
* i386-linux-tdep.c (i386_linux_init_abi): Remove size_dirent{,64},
add size_old_dirent.
* linux-record.c (record_linux_system_call): Fix handling of readdir
and getdents{,64}.
* linux-record.h (struct linux_record_tdep): Remove size_dirent{,64},
add size_old_dirent.
* ppc-linux-tdep.c (ppc_init_linux_record_tdep): Remove
size_dirent{,64}, add size_old_dirent.
i386 and arm wrongly set them to 2, when it should be 4. size_[ug]id is used
by getgroups32 etc syscalls, while size_old_[ug]id is used for getgroups16
and friends.
gdb/ChangeLog:
* arm-linux-tdep.c (arm_linux_init_abi): Fix size_[ug]id.
* i386-linux-tdep.c (i386_linux_init_abi): Fix size_[ug]id.
gdb/testsuite/ChangeLog:
* gdb.reverse/fstatat-reverse.c: New test.
* gdb.reverse/fstatat-reverse.exp: New file.
* gdb.reverse/getresuid-reverse.c: New test.
* gdb.reverse/getresuid-reverse.exp: New file.
* gdb.reverse/pipe-reverse.c: New test.
* gdb.reverse/pipe-reverse.exp: New file.
* gdb.reverse/readv-reverse.c: New test.
* gdb.reverse/readv-reverse.exp: New file.
* gdb.reverse/recvmsg-reverse.c: New test.
* gdb.reverse/recvmsg-reverse.exp: New file.
* gdb.reverse/time-reverse.c: New test.
* gdb.reverse/time-reverse.exp: New file.
* gdb.reverse/waitpid-reverse.c: New test.
* gdb.reverse/waitpid-reverse.exp: New file.
Fixes on i386:
../../../binutils-gdb/gdb/gdbserver/proc-service.c: In function ps_pdread:
../../../binutils-gdb/gdb/gdbserver/proc-service.c:83:25: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
../../../binutils-gdb/gdb/gdbserver/proc-service.c: In function ps_pdwrite:
../../../binutils-gdb/gdb/gdbserver/proc-service.c:93:30: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
I could have kept both casts:
(CORE_ADDR) (uintptr_t) addr
but it's cleaner this way. The uintptr_t implicitely gets promoted to a
CORE_ADDR, which is at least as long as uintptr_t.
gdb/gdbserver/ChangeLog:
* proc-service.c (ps_pdread): Change CORE_ADDR cast to uintptr_t.
(ps_pdwrite): Likewise.
gdb/gdbserver/ChangeLog:
* linux-arm-low.c (arm_new_thread): Move pointer dereference
to after assert checks.
Signed-off-by: Henrik Wallin <henrik.wallin@windriver.com>
The casts are required because ps_pd{read,write} must respect a fixed
interface.
gdb/gdbserver/ChangeLog:
* proc-service.c (ps_pdread): Add/adjust casts.
(ps_pdwrite): Add/adjust casts.
This fixes this error in C++ mode:
/home/pedro/gdb/mygit/cxx-convertion/src/gdb/mdebugread.c:654:11: error: invalid conversion from ‘int’ to ‘address_class’ [-fpermissive]
theclass = mdebug_register_index;
^
The "theclass" local is of type enum address_class, however, what it
really holds is an address class index. Class index values by design
match the address class values up until LOC_FINAL_VALUE, but extend
beyond that, so it's not really right to store an address class index
in an enum address_class.
The fix is really the same making the 'theclass' local be of type int,
but while we're at it, we get rid of the goto, and thus the local
becomes the 'aclass_index' parameter in the new add_data_symbol
function.
gdb/ChangeLog:
2015-10-29 Pedro Alves <palves@redhat.com>
* mdebugread.c (add_data_symbol): New function, factored out from
...
(parse_symbol): ... here. Delete 'theclass' local.
We could change the signature of the function. However, it would
require changing gdb_target_read in jit-reader.h, which is an exported
interface. It's probably better to just add a cast in our code than to
break other people's code.
gdb/ChangeLog:
* jit.c (jit_target_read_impl): Add cast.
There is no enum value representing 0. It seems like the value of the
name field is irrelevant here.
gdb/ChangeLog:
* dwarf2read.c (partial_die_full_name): Add cast.
Fixes this in C++:
../../src/gdb/break-catch-sig.c: In function ‘int VEC_gdb_signal_type_iterate(const VEC_gdb_signal_type*, unsigned int, gdb_signal_type*)’:
../../src/gdb/common/vec.h:576:12: error: invalid conversion from ‘int’ to ‘gdb_signal_type {aka gdb_signal}’ [-fpermissive]
*ptr = 0; \
^
../../src/gdb/common/vec.h:417:1: note: in expansion of macro ‘DEF_VEC_FUNC_P’
DEF_VEC_FUNC_P(T) \
^
../../src/gdb/break-catch-sig.c:37:1: note: in expansion of macro ‘DEF_VEC_I’
DEF_VEC_I (gdb_signal_type);
^
I actually carried a different fix in the C++ branch that removed this
assignment and then adjusted all callers that depended on it. The
thinking was that this is for the case where we're returning false,
indicating end of iteration. But that results in a much larger and
tricker patch; looking back it seems quite pointless. I looked at the
history of GCC's C++ conversion and saw that they added this same cast
to their version of vec.h, FWIW. (GCC's vec.h is completely different
nowadays, having been converted to templates meanwhile.)
gdb/ChangeLog:
2015-10-29 Pedro Alves <palves@redhat.com>
* common/vec.h (DEF_VEC_FUNC_P) [iterate]: Cast 0 to type T.
I looked at changing these is_destructor_name/is_constructor_name
interfaces in order to detangle the boolean result from the ctor/dtor
kind return, but then realized that this design goes all the way down
to the libiberty demangler interfaces. E.g, include/demangle.h:
~~~
/* Return non-zero iff NAME is the mangled form of a constructor name
in the G++ V3 ABI demangling style. Specifically, return an `enum
gnu_v3_ctor_kinds' value indicating what kind of constructor
it is. */
extern enum gnu_v3_ctor_kinds
is_gnu_v3_mangled_ctor (const char *name);
enum gnu_v3_dtor_kinds {
gnu_v3_deleting_dtor = 1,
gnu_v3_complete_object_dtor,
gnu_v3_base_object_dtor,
/* These are not part of the V3 ABI. Unified destructors are generated
as a speed-for-space optimization when the -fdeclone-ctor-dtor option
is used, and are always internal symbols. */
gnu_v3_unified_dtor,
gnu_v3_object_dtor_group
};
~~~
libiberty/cp-demangle.c:
~~~
enum gnu_v3_ctor_kinds
is_gnu_v3_mangled_ctor (const char *name)
{
enum gnu_v3_ctor_kinds ctor_kind;
enum gnu_v3_dtor_kinds dtor_kind;
if (! is_ctor_or_dtor (name, &ctor_kind, &dtor_kind))
return (enum gnu_v3_ctor_kinds) 0;
return ctor_kind;
}
~~~
etc.
gdb/ChangeLog:
2015-10-29 Pedro Alves <palves@redhat.com>
* gnu-v2-abi.c (gnuv2_is_destructor_name)
(gnuv2_is_constructor_name): Add casts.
The GOT entry size is target-dependent. This patch adds a got_entry_size
function to Sized_target class so that a target can provide a value
different from default.
PR gold/19184
* incremental.cc (Got_plt_view_info): Add got_entry_size.
(Local_got_offset_visitor::visit): Replace got_entry_size_
with info_.got_entry_size.
(Local_got_offset_visitor::got_entry_size_): Removed.
(Global_got_offset_visitor::visit): Replace got_entry_size_
with info_.got_entry_size.
(Global_got_offset_visitor::got_entry_size_): Removed.
(Output_section_incremental_inputs::write_got_plt): Initialize
view_info.got_entry_size.
* target.h (Sized_target::got_entry_size): New virtual function.
* x86_64.cc (Target_x86_64::got_entry_size): New function.
bfd/
* elfxx-mips.c (mips_elf_check_mips16_stubs): Set a stub's output
section to bfd_abs_section_ptr if the stub is discarded.
ld/testsuite/
* ld-mips-elf/mips16-fp-stub-1.s: New.
* ld-mips-elf/mips16-fp-stub-2.s: New.
* ld-mips-elf/mips16-fp-stub.d: New.
* ld-mips-elf/mips-elf.exp: Run new tests.
* ld-mips-elf/mips16-intermix.d: Update expected output.
https://sourceware.org/ml/binutils/2015-10/msg00137.html
ld * Makefile.am (ALL_64_EMULATION_SOURCES): Add support for
CloudABI on aarch64. For this target we have to make sure we use
ELFOSABI_CLOUDABI instead of ELFOSABI_NONE.
* configure.tgt (targ_emul): Likewise.
* emulparams/aarch64cloudabi.sh: New file.
* emulparams/aarch64cloudabib.sh: New file.
* Makefile.in: Regenerate.
bfd * config.bfd (targ_defvec): Add support for CloudABI on aarch64.
For this target we have to make sure we use ELFOSABI_CLOUDABI
instead of ELFOSABI_NONE.
* configure.ac (tb): Likewise.
* elfnn-aarch64.c: Likewise.
* targets.c (_bfd_target_vector): Likewise.
* configure: Regenerate.
gas * config/tc-aarch64.c (elf64_aarch64_target_format): Select the
cloudabi format if the TARGET_OS is cloudabi.
Fixes this when GDB is built in C++ mode:
In file included from /home/pedro/gdb/mygit/src/gdb/../bfd/som.h:27:0,
from /home/pedro/gdb/mygit/src/gdb/somread.c:31:
/home/pedro/gdb/mygit/src/gdb/../bfd/libhppa.h: In function ‘int bfd_hppa_insn2fmt(bfd*, int)’:
/home/pedro/gdb/mygit/src/gdb/../bfd/libhppa.h:380:42: error: invalid conversion from ‘int’ to ‘hppa_opcode_type’ [-fpermissive]
#define get_opcode(insn) (((insn) >> 26) & 0x3f)
^
/home/pedro/gdb/mygit/src/gdb/../bfd/libhppa.h:465:30: note: in expansion of macro ‘get_opcode’
enum hppa_opcode_type op = get_opcode (insn);
^
bfd/ChangeLog:
2015-10-29 Pedro Alves <palves@redhat.com>
* libhppa.h (bfd_hppa_insn2fmt): Add cast.
... for C++.
Fixes:
gdb/gdbserver/mem-break.c:204:28: error: invalid conversion from 'int' to 'bkpt_type' [-fpermissive]
gdb/gdbserver/ChangeLog:
2015-10-29 Pedro Alves <palves@redhat.com>
* mem-break.c (Z_packet_to_bkpt_type): Add cast.
... as needed for C++.
tpoint->handle is a generic 'void *' handle.
gdb/gdbserver/ChangeLog:
2015-10-29 Pedro Alves <palves@redhat.com>
* tracepoint.c (clear_installed_tracepoints): Add casts.
This is code parsing RSP signal numbers, checking whether the numbers
are indeed valid/known GDB signals, and then converting to host signal
numbers. I considered adding temporary enum gdb_signal variables
instead, but didn't really like the result.
gdb/gdbserver/ChangeLog:
2015-10-29 Pedro Alves <palves@redhat.com>
* server.c (handle_v_cont, process_serial_event): Add enum
gdb_signal casts to signal parsing code.
Fixes:
../../../src/gdb/gdbserver/linux-low.c: In function ‘int linux_low_read_btrace(btrace_target_info*, buffer*, int)’:
../../../src/gdb/gdbserver/linux-low.c:6827:48: error: invalid conversion from ‘int’ to ‘btrace_read_type’ [-fpermissive]
err = linux_read_btrace (&btrace, tinfo, type);
^
In file included from ../../../src/gdb/gdbserver/linux-low.c:98:0:
../../../src/gdb/gdbserver/../nat/linux-btrace.h:116:26: error: initializing argument 3 of ‘btrace_error linux_read_btrace(btrace_data*, btrace_target_info*, btrace_read_type)’ [-fpermissive]
extern enum btrace_error linux_read_btrace (struct btrace_data *btrace,
^
The cyclic dependency the comment talks about is no longer relevant:
https://sourceware.org/ml/gdb-patches/2015-10/msg00643.html
gdb/gdbserver/ChangeLog:
2015-10-29 Pedro Alves <palves@redhat.com>
* linux-low.c (linux_low_read_btrace): Change type of 'type'
parameter.
* server.c (handle_qxfer_btrace): Change type of 'type'
local.
* target.h (struct target_ops) <read_btrace>: Change type of
'type' parameter. Update comment.
Fixes, in C++ mode:
../../src/gdb/common/common-exceptions.c:23:69: error: invalid conversion from ‘int’ to ‘return_reason’ [-fpermissive]
const struct gdb_exception exception_none = { 0, GDB_NO_ERROR, NULL };
^
(I considered adding an enum value for '0', but the code and comments
around return_reason and its uses explain how 0 is special/internal,
so I'm leaving it be.)
gdb/ChangeLog:
2015-10-29 Pedro Alves <palves@redhat.com>
* common/common-exceptions.c (exception_none): Add cast.
Fixes:
src/gdb/compile/compile-c-types.c:36:12: error: declaration of ‘gcc_type type_map_instance::gcc_type’ [-fpermissive]
gcc_type gcc_type;
^
In file included from src/gdb/../include/gcc-c-interface.h:23:0,
from src/gdb/compile/compile-internal.h:21,
from src/gdb/compile/compile-c-types.c:23:
src/gdb/../include/gcc-interface.h:32:28: error: changes meaning of ‘gcc_type’ from ‘typedef long long unsigned int gcc_type’ [-fpermissive]
typedef unsigned long long gcc_type;
^
src/gdb/compile/compile-c-types.c: In function ‘gcc_type convert_qualified(compile_c_instance*, type*)’:
src/gdb/compile/compile-c-types.c:310:19: error: invalid conversion from ‘int’ to ‘gcc_qualifiers’ [-fpermissive]
quals);
^
gdb/ChangeLog:
2015-10-29 Pedro Alves <palves@redhat.com>
* compile/compile-c-types.c (struct type_map_instance)
<gcc_type>: Rename to gcc_type_handle.
(insert_type, convert_type): Adjust.
In C++, this:
try
{
break;
}
catch (..)
{}
is invalid. However, because our TRY/CATCH macros support it in C,
the C++ version of those macros support it too. To catch such
assumptions, this adds a (disabled) hack that maps TRY/CATCH to raw
C++ try/catch. Then it goes through all instances that building on
x86_64 GNU/Linux trips on, fixing them.
This isn't strictly necessary yet, but I think it's nicer to try to
keep the tree in a state where it's easier to eliminate the TRY/CATCH
macros.
gdb/ChangeLog:
2015-10-29 Pedro Alves <palves@redhat.com>
* dwarf2-frame-tailcall.c (dwarf2_tailcall_sniffer_first): Don't
assume that "break" breaks out of a TRY/CATCH.
* python/py-framefilter.c (py_print_single_arg): Don't assume
"continue" breaks out of a TRY/CATCH.
* python/py-value.c (valpy_binop_throw): New function, factored
out from ...
(valpy_binop): ... this.
(valpy_richcompare_throw): New function, factored
out from ...
(valpy_richcompare): ... this.
* solib.c (solib_read_symbols): Don't assume "break" breaks out
of a TRY/CATCH.
* common/common-exceptions.h [USE_RAW_CXX_TRY]
<TRY/CATCH/END_CATCH>: Define as 1-1 wrappers around try/catch.
PR ld/19146
* lexsup.c (parse_args): Correct error message for an option that
is missing its argument if that option is the last one on the
command line.
The last patch missed handling the case where the ideal place to put
an orphan was after a non-existent output section statement, as can
happen when not using the builtin linker scripts. This patch uses the
updated flags for that case too, and extends the support to mmo and pe.
PR ld/19162
* emultempl/elf32.em (gld${EMULATION_NAME}_place_orphan): Pass
updated flags to lang_output_section_find_by_flags.
* emultempl/mmo.em (mmo_place_orphan): Merge flags for any
other input sections that might match a new output section to
decide placement.
* emultempl/pe.em (gld_${EMULATION_NAME}_place_orphan): Likewise.
* emultempl/pep.em (gld_${EMULATION_NAME}_place_orphan): Likewise.
* ldlang.c (lang_output_section_find_by_flags): Add sec_flags param.
* ldlang.h (lang_output_section_find_by_flags): Update prototype.
