This new option, disabled by default for now, allows specifying
whether to build GDB, GDBserver, and friends with a C++ (98/03)
compiler.
The name of the switch should be familiar to those who followed GCC's
own C++ conversion process.
. Adding -fpermissive to COMPILER in C++ mode (see the new
build-with-cxx.m4 file) makes errors like these be warnings instead:
gdb/infrun.c:6597:1: error: initializing argument 1 of ‘void sig_print_info(gdb_signal)’ [-fpermissive]
sig_print_info (enum gdb_signal oursig)
^
gdb/infrun.c: In function ‘void do_restore_infcall_suspend_state_cleanup(void*)’:
gdb/infrun.c:7164:39: error: invalid conversion from ‘void*’ to ‘infcall_suspend_state*’ [-fpermissive]
restore_infcall_suspend_state (state);
^
so that the compiler carries on compiling the file. -Werror still
catches the warnings, so nothing is lost, only our lifes are made
easier by concentrating on getting other more important things out of
the way first.
There's no way to quiet those warnings. Until they're all fixed, when
building in C++ mode, -Werror is disabled by default.
. Adding -Wno-narrowing suppresses thousands of instances of this warning:
gdb/arm-linux-tdep.c:439:1: error: narrowing conversion of ‘-1’ from ‘int’ to ‘ULONGEST {aka long unsigned int}’ inside { } is ill-formed in C++11 [-Werror=narrowing]
gdb/arm-linux-tdep.c:439:1: error: narrowing conversion of ‘-1l’ from ‘LONGEST {aka long int}’ to ‘ULONGEST {aka long unsigned int}’ inside { } is ill-formed in C++11 [-Werror=narrowing]
gdb/arm-linux-tdep.c:450:1: error: narrowing conversion of ‘-1’ from ‘int’ to ‘ULONGEST {aka long unsigned int}’ inside { } is ill-formed in C++11 [-Werror=narrowing]
We can defer handling those until we target C++11.
. Adding -Wno-sign-compare suppresses thousands of instances of this warning:
gdb/linux-record.c:1763:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if (tmpulongest == tdep->fcntl_F_GETLK64)
^
. Adding -Wno-write-strings suppresses thousands of instances of this warning:
gdb/mi/mi-cmd-var.c: In function ‘void mi_cmd_var_show_attributes(char*, char**, int)’:
gdb/mi/mi-cmd-var.c:514:12: warning: deprecated conversion from string constant to ‘char*’ [-Wwrite-strings]
attstr = "editable";
^
gdb/mi/mi-cmd-var.c:516:12: warning: deprecated conversion from string constant to ‘char*’ [-Wwrite-strings]
attstr = "noneditable";
^
For now, it's best to hide these warnings from view until we're
'-fpermissive'-clean, and can thus start building with -Werror.
The C compiler has always managed to build working GDBs with these
issues in the code, so a C++ compiler should too.
gdb/ChangeLog:
2015-02-27 Pedro Alves <palves@redhat.com>
* Makefile.in (COMPILER): New, get it from autoconf.
(COMPILE.pre, CC_LD): Use COMPILER.
(CXX): Get from autoconf instead.
(CXX_FOR_TARGET): Default to g++ instead of gcc.
* acinclude.m4: Include build-with-cxx.m4.
* build-with-cxx.m4: New file.
* configure.ac: Call AC_PROG_CXX and GDB_AC_BUILD_WITH_CXX.
Disable -Werror by default if building in C++ mode.
(build_warnings): Add -Wno-sign-compare, -Wno-write-strings and
-Wno-narrowing in C++ mode. Only enable -Wpointer-sign in C mode.
Run supported-warning-flags tests with the C++ compiler.
Save/restore CXXFLAGS too.
* configure: Regenerate.
gdb/gdbserver/ChangeLog:
2015-02-27 Pedro Alves <palves@redhat.com>
* Makefile.in (COMPILER): New, get it from autoconf.
(CXX): Get from autoconf instead.
(COMPILE.pre): Use COMPILER.
(CC-LD): Rename to ...
(CC_LD): ... this. Use COMPILER.
(gdbserver$(EXEEXT), gdbreplay$(EXEEXT), $(IPA_LIB)): Adjust.
(CXX_FOR_TARGET): Default to g++ instead of gcc.
* acinclude.m4: Include build-with-cxx.m4.
* configure.ac: Call AC_PROG_CXX and GDB_AC_BUILD_WITH_CXX.
Disable -Werror by default if building in C++ mode.
(build_warnings): Add -Wno-sign-compare, -Wno-write-strings and
-Wno-narrowing in C++ mode. Run supported-warning-flags tests with
the C++ compiler. Save/restore CXXFLAGS too.
* configure: Regenerate.
Converting GDB to be a C++ program, I stumbled on 'basename' issues,
like:
src/gdb/../include/ansidecl.h:169:64: error: new declaration ‘char* basename(const char*)’
/usr/include/string.h:597:26: error: ambiguates old declaration ‘const char* basename(const char*)’
which I believe led to this bit in gold's configure.ac:
dnl We have to check these in C, not C++, because autoconf generates
dnl tests which have no type information, and current glibc provides
dnl multiple declarations of functions like basename when compiling
dnl with C++.
AC_CHECK_DECLS([basename, ffs, asprintf, vasprintf, snprintf, vsnprintf, strverscmp])
These checks IIUC intend to generate all the HAVE_DECL_FOO symbols
that libiberty.h and ansidecl.h check.
GDB is missing these checks currently, which results in the conflict
shown above.
This adds an m4 file that both GDB and GDBserver's configury use to
pull in the autoconf checks that libiberty clients needs done in order
to use these libiberty.h/ansidecl.h.
gdb/ChangeLog:
2015-02-27 Pedro Alves <palves@redhat.com>
* libiberty.m4: New file.
* acinclude.m4: Include libiberty.m4.
* configure.ac: Call libiberty_INIT.
* config.in, configure: Regenerate.
gdb/gdbserver/
2015-02-27 Pedro Alves <palves@redhat.com>
* acinclude.m4: Include libiberty.m4.
* configure.ac: Call libiberty_INIT.
* config.in, configure: Regenerate.
In some scenarios, GDB or GDBserver can be spawned with input _not_
connected to a tty, and then tests that rely on stdio fail with
timeouts, because the inferior's stdout and stderr streams end up
fully buffered.
See discussion here:
https://sourceware.org/ml/gdb-patches/2015-02/msg00809.html
We have a hack in place that works around this for Windows testing,
that forces every test program to link with an .o file that does
(lib/set_unbuffered_mode.c):
static int __gdb_set_unbuffered_output (void) __attribute__ ((constructor));
static int
__gdb_set_unbuffered_output (void)
{
setvbuf (stdout, NULL, _IONBF, BUFSIZ);
setvbuf (stderr, NULL, _IONBF, BUFSIZ);
}
That's a bit hacky; it ends up done for _all_ tests.
This patch adds a way to do this unbuffering explicitly from the test
code itself, so it is done only when necessary, and for all
targets/hosts. For starters, it adjusts gdb.base/interrupt.c to use
it.
Tested on x86_64 Fedora 20, native, and against a remote gdbserver
board file that connects to the target with ssh, with and without -t
(create pty).
gdb/testsuite/
2015-02-27 Pedro Alves <palves@redhat.com>
* lib/unbuffer_output.c: New file.
* gdb.base/interrupt.c: Include "../lib/unbuffer_output.c".
(main): Call gdb_unbuffer_output.
As far as I know, "catch syscall" is supported on hppa*-hp-hpux*, but
the test catch-syscall.exp is skipped on this target by mistake. This
patch is to fix it. However, I don't have a hpux machine to test.
gdb/testsuite:
2015-02-27 Yao Qi <yao.qi@linaro.org>
* gdb.base/catch-syscall.exp: Don't skip it on hppa*-hp-hpux*
target.
On 64-bit S390 platforms the "compile" command always failed because
gcc was not invoked correctly. This patch fixes the compiler
invocation.
gdb/ChangeLog:
* s390-linux-tdep.c (s390_gcc_target_options): Not just handle
31-bit targets, but 64-bit targets as well.
(s390_gnu_triplet_regexp): New function.
(s390_gdbarch_init): Set the gcc_target_options gdbarch method for
64-bit targets as well. Set the gnu_triplet_regexp gdbarch
method.
For amd64, CONTEXT_FULL does not contain CONTEXT_SEGMENTS, which seems
to be needed to retrieve all the segment registers. Add it explicitly,
with a little de-cruftification.
The value of the segment registers isn't terribly useful on amd64, but
at least this makes the output of 'info registers' correct.
Before:
(gdb) i r cs ss ds es fs gs
cs 0x33 51
ss 0x2b 43
ds 0x0 0
es 0x0 0
fs 0x0 0
gs 0x0 0
After:
(gdb) i r cs ss ds es fs gs
cs 0x33 51
ss 0x2b 43
ds 0x2b 43
es 0x2b 43
fs 0x53 83
gs 0x2b 43
gdb/ChangeLog
2015-02-27 Jon TURNEY <jon.turney@dronecode.org.uk>
* windows-nat.c (CONTEXT_DEBUGGER): Remove.
(CONTEXT_DEBUGGER_DR): Add CONTEXT_SEGMENTS. Incorporate flags
from CONTEXT_DEBUGGER.
Extend the address modifier parsing to distinguish between the
modifers used in LDR literal and LDR register offset address modes.
The current parser incorrectly accepts the :got: modifier on a
register offset instruction resulting in silent corruption of the
output binary.
The current implementation of the :got: assembler modifier does not
distinguish the ADR and ADRP instruction. The :got: modifier does not
make sense on and ADR instruction and should be error'd rather than
the current behavior of applying an inappropriate relocation to the
output and scrambling the underlying instruction silently.
The HOWTO table entries for the TLSLE_MOVW_TPREL_* relocations are
wrong by inspection. The current implementation does not actually use
these field widths for these relocations but they should be corrected.
PR binutils/17512
* coffgrok.c (do_type): Check for an out of range tag index.
Check for integer overflow computing array dimension.
(do_define): Likewise.
.decr_pc_after_break is never higher than .breakpoint_len, so use
.breakpoint_len directly. Based on idea from Yao here:
https://sourceware.org/ml/gdb-patches/2015-02/msg00689.html
gdb/gdbserver/ChangeLog:
2015-02-26 Pedro Alves <palves@redhat.com>
* linux-low.c (linux_wait_1): When incrementing the PC past a
program breakpoint always use the_low_target.breakpoint_len as
increment, rather than the maximum between that and
the_low_target.decr_pc_after_break.
Fixes building gdb on x86_64-apple-darwin14 with clang, which produces
a number of warnings from -Wformat-nonliteral.
Ref: https://sourceware.org/ml/gdb/2015-02/msg00047.html
gdb/ChangeLog:
2015-02-26 Pedro Alves <palves@redhat.com>
* auto-load.h (file_is_auto_load_safe): Add ATTRIBUTE_PRINTF.
* complaints.c (vcomplaint): Pass argument FMT directly to
printf-like functions instead of complaint->fmt.
* ctf.c (ctf_save_write_metadata): Add ATTRIBUTE_PRINTF.
* darwin-nat.c (inferior_debug): Add ATTRIBUTE_PRINTF.
* compile/compile-loc2c.c (pushf, unary, binary): Add
ATTRIBUTE_PRINTF.
(do_compile_dwarf_expr_to_c): Pass string literal as format string
to pushf.
(BINARY): Pass string literal as format string to 'binary'.
* compile/compile-object-load.c (link_callbacks_einfo): Add
ATTRIBUTE_PRINTF.
* guile/guile-internal.h (gdbscm_printf): Add ATTRIBUTE_PRINTF.
In commit 7173b38a44 I used optarg as the
name for a function parameter, shadowing the global of that name. This
commit changes the function parameter to be called arg.
binutils/ChangeLog:
* objcopy.c (init_section_add): Rename optarg to arg in order to
avoid shadowing a global variable.
Preparation for using this on all hosts.
Confirmed that --host=x86_64-w64-mingw32 still builds the stub
termcap.
gdb/ChangeLog:
2015-02-26 Pedro Alves <palves@redhat.com>
* windows-termcap.c: Rename to ...
* stub-termcap.c: ... this. Adjust header line.
* Makefile.in (SFILES): Refer to stub-termcap.c instead of
windows-termcap.c.
* configure: Regenerate.
* configure.ac: Refer to stub-termcap.o instead of
windows-termcap.o.
* gdb_curses.h: Mention stub-termcap.c instead of
windows-termcap.c.
One could not call IFUNCs (=indirect functions) from the compiled injected
code. Either it errored with:
gdb command line:1:1: error: function return type cannot be function
or it just called the IFUNC dispatcher in normal way, returning real function
implementation address instead of the function return value (and thus no
function was called).
gdb/ChangeLog
2015-02-26 Jan Kratochvil <jan.kratochvil@redhat.com>
* compile/compile-c-symbols.c (convert_one_symbol, convert_symbol_bmsym)
(gcc_symbol_address): Call gnu_ifunc_resolve_addr.
gdb/testsuite/ChangeLog
2015-02-26 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.compile/compile-ifunc.c: New file.
* gdb.compile/compile-ifunc.exp: New file.
When doing finish in a function, if gdb fails to return a value, gdb
also fails at printing the value type if this type is a struct.
For example :
(gdb) fin
....
Value returned has type: . Cannot determine contents
This patch fixes this by calling type_to_string to print the type
so that we can support these types.
This patch returns the following example output :
(gdb) fin
....
Value returned has type: struct test. Cannot determine contents
Also, this patch modifies structs.exp to check that we return the
correct type.
gdb/ChangeLog:
* gdb/infcmd.c (print_return_value): use type_to_string to print type.
gdb/testsuite/ChangeLog:
* gdb.base/structs.exp: Check for correct struct on finish.
PR binutils/17512
* dwarf.c (display_debug_loc): Pacify the undefined behaviour
sanitizer by simplifying address difference calculation.
(struct Frame_Chunk): Change type of cfa_offset to dwarf_vma in
order to avoid arithmetic overflows.
(frame_display_row): Cast cfa_offset before printing it.
(display_debug_frames): Likewise.
Check for an unexpected segment size.
Chnage type of 'l' local to dwarf_vma and cast it back to an int
when printing.
(process_cu_tu_index): Tighten check for an invalid ncols value.
* readelf.c (process_corefile_note_segment): Check for
inote.descdata extending beyond the end of the section.
(process_v850_notes): Likewise.
On aarch64, we got the following fail:
(gdb) disassemble func
Dump of assembler code for function func:
0x0000000000400730 <+0>: ret
End of assembler dump.^M
(gdb) x/2i func+0^M
0x400730 <func>: ret^M
0x400734 <main>: stp x29, x30, [sp,#-16]!^M
(gdb) FAIL: gdb.dwarf2/dw2-ifort-parameter.exp: x/2i func+0
the pattern in proc function_range expects to match <func+0>, however,
GDB doesn't display the offset when it is zero. This patch is to
adjust the pattern when $func_length is zero.
gdb/testsuite:
2015-02-26 Yao Qi <yao.qi@linaro.org>
* lib/dwarf.exp (function_range): Adjust pattern when $func_length
is zero.
The attached patch fixes the SEGV and lets GDB successfully
load all kernel modules installed by default on RHEL 7.
Valgrind on F-21 x86_64 host has shown me more clear what is the problem:
Reading symbols from /home/jkratoch/t/cordic.ko...Reading symbols from
/home/jkratoch/t/cordic.ko.debug...=================================================================
==22763==ERROR: AddressSanitizer: heap-use-after-free on address 0x6120000461c8 at pc 0x150cdbd bp 0x7fffffffc7e0 sp 0x7fffffffc7d0
READ of size 8 at 0x6120000461c8 thread T0
#0 0x150cdbc in ppc64_elf_get_synthetic_symtab /home/jkratoch/redhat/gdb-test-asan/bfd/elf64-ppc.c:3282
#1 0x8c5274 in elf_read_minimal_symbols /home/jkratoch/redhat/gdb-test-asan/gdb/elfread.c:1205
#2 0x8c55e7 in elf_symfile_read /home/jkratoch/redhat/gdb-test-asan/gdb/elfread.c:1268
[...]
0x6120000461c8 is located 264 bytes inside of 288-byte region [0x6120000460c0,0x6120000461e0)
freed by thread T0 here:
#0 0x7ffff715454f in __interceptor_free (/lib64/libasan.so.1+0x5754f)
#1 0xde9cde in xfree common/common-utils.c:98
#2 0x9a04f7 in do_my_cleanups common/cleanups.c:155
#3 0x9a05d3 in do_cleanups common/cleanups.c:177
#4 0x8c538a in elf_read_minimal_symbols /home/jkratoch/redhat/gdb-test-asan/gdb/elfread.c:1229
#5 0x8c55e7 in elf_symfile_read /home/jkratoch/redhat/gdb-test-asan/gdb/elfread.c:1268
[...]
previously allocated by thread T0 here:
#0 0x7ffff71547c7 in malloc (/lib64/libasan.so.1+0x577c7)
#1 0xde9b95 in xmalloc common/common-utils.c:41
#2 0x8c4da2 in elf_read_minimal_symbols /home/jkratoch/redhat/gdb-test-asan/gdb/elfread.c:1147
#3 0x8c55e7 in elf_symfile_read /home/jkratoch/redhat/gdb-test-asan/gdb/elfread.c:1268
[...]
SUMMARY: AddressSanitizer: heap-use-after-free /home/jkratoch/redhat/gdb-test-asan/bfd/elf64-ppc.c:3282 ppc64_elf_get_synthetic_symtab
[...]
==22763==ABORTING
A similar case a few lines later I have fixed in 2010 by:
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=3f1eff0a2c7f0e7078f011f55b8e7f710aae0cc2
My testcase does not always reproduce it but at least a bit:
* GDB without ppc64 target (even as a secondary one) is reported as "untested"
* ASAN-built GDB with ppc64 target always crashes (and PASSes with this fix)
* unpatched non-ASAN-built GDB with ppc64 target crashes from commandline
* unpatched non-ASAN-built GDB with ppc64 target PASSes from runtest (?)
gdb/ChangeLog
2015-02-26 Jan Kratochvil <jan.kratochvil@redhat.com>
* elfread.c (elf_read_minimal_symbols): Use bfd_alloc for
bfd_canonicalize_symtab.
gdb/testsuite/ChangeLog
2015-02-26 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.arch/cordic.ko.bz2: New file.
* gdb.arch/cordic.ko.debug.bz2: New file.
* gdb.arch/ppc64-symtab-cordic.exp: New file.
I was looking at a current glibc using objdump today and saw an odd
plt call stub.
0000000000044d80 <00000033.plt_call.__strchrnul>:
44d80: f8 41 00 28 std r2,40(r1)
44d84: e9 82 8c f8 ld r12,-29448(r2)
44d88: 7d 89 03 a6 mtctr r12
44d8c: e8 42 8d 00 ld r2,-29440(r2)
44d90: 28 22 00 00 cmpldi r2,0
44d94: 4c e2 04 20 bnectr+
44d98: 48 13 84 f0 b 17d288 <realloc@plt>
What? It doesn't branch to __strchrnul@plt on finding a zero r2?
Turns out this isn't a real problem since the stub is for loading an
ifunc, so will not be lazily resolved and thus r2 will never be zero.
Of course, that means the thread-safety check is unnecessary.
I also tweak the special __tls_get_addr_opt call stub here, to
restore r2 immediately after the call. Not doing that might affect
eh_frame unwinding.
* elf64-ppc.c (plt_stub_size, build_plt_stub): Don't build
thread-safe stubs for iplt.
(build_tls_get_addr_stub): Restore r2 immediately after call.
- Use signal frame sniffers that look for the signal trampoline
instruction sequence to detect most signal frames.
- FreeBSD kernels between 9.2 and 10.1 inclusive do not include the
signal trampoline code in process core dumps. To detect signal
frames for core dumps under these kernels, use the
kern.proc.sigtramp.<pid> sysctl to fetch the location of the signal
trampoline in the gdb process and assume that PC values within this
location are signal frames. This depends on that location being
identical for all binaries.
gdb/ChangeLog:
2015-02-25 John Baldwin <jhb@FreeBSD.org>
* amd64fbsd-nat.c: Include sys/user.h.
(_initialize_amd64fbsd_nat): Use the KERN_PROC_SIGTRAMP sysctl
instead of KERN_PS_STRINGS to locate the signal trampoline.
* i386fbsd-nat.c: Include sys/user.h.
(_initialize_i386fbsd_nat): Use the KERN_PROC_SIGTRAMP sysctl
instead of KERN_PS_STRINGS to locate the signal trampoline.
* amd64fbsd-tdep.c (amd64fbsd_sigtramp_code): New.
(amd64fbsd_sigtramp_p): New.
(amd64fbsd_sigtramp_start_addr, amd64fbsd_sigtramp_end_addr): No
longer set default values.
(amd64fbsd_init_abi): Set "sigtramp_p" to "amd64fbsd_sigtramp_p".
* i386fbsd-tdep.c (i386fbsd_sigtramp_start)
(i386fbsd_sigtramp_middle, i386fbsd_sigtramp_end)
(i386fbsd_freebsd4_sigtramp_start)
(i386fbsd_freebsd4_sigtramp_middle)
(i386fbsd_freebsd4_sigtramp_end, i386fbsd_osigtramp_start)
(i386fbsd_osigtramp_middle, i386fbsd_osigtramp_end): New.
(i386fbsd_sigtramp_p): New.
(i386fbsd_sigtramp_start_addr, i386fbsd_sigtramp_end_addr): No
longer set default values.
(i386fbsd_init_abi): Set "sigtramp_p" to "i386fbsd_sigtramp_p".
amd64fbsd_sigcontext_addr is using frame_unwind_register_unsigned to
fetch the stack pointer which results in infinite recursion. This
patch changes it to use get_frame_register to match the
sigcontext_addr methods in the i386-bsd and amd64-linux targets
instead.
gdb/ChangeLog:
2015-02-25 John Baldwin <jhb@freebsd.org>
* amd64fbsd-tdep.c (amd64fbsd_sigcontext_addr): Use
get_frame_register instead of frame_unwind_register_unsigned.
Rather than reporting a link error on attempting to use dynbss for
protected vars, use dynamic text relocs.
* elf32-ppc.c (ppc_elf_adjust_dynamic_symbol): Heed -z nocopyreloc.
Use text relocs rather than giving an error on trying to use
.dynbss for protected shared lib vars.
* elf64-ppc.c (ppc64_elf_adjust_dynamic_symbol): Likewise.
