TERNOP_SLICE was added for language Chill, but it is used for Ada and D later.
Since language Chill was removed from GDB, TERNOP_SLICE is only used for
Ada and D. This patch is to update its comments.
gdb:
2014-07-20 Yao Qi <yao@codesourcery.com>
* std-operator.def: Update comments to TERNOP_SLICE.
BINOP_RANGE was added by the following commit for chill language.
commit badefd2800
Author: Per Bothner <per@bothner.com>
Date: Wed Nov 29 22:59:31 1995 +0000
* expression.h (enum exp_opcode): Add BINOP_RANGE.
* expprint.c (dump_expression): Support BINOP_RANGE.
* eval.c (evaluate_subexp_standard): Handle BINOP_RANGE (as error).
(case MULTI_SUBSCRIPT): Fix broken f77 value->int ad hoc conversion.
* ch-lang.c (chill_op_print_tab): Support BINOP_RANGE.
(evaluate_subexp_chill): Error on BINOP_COMMA.
Chill language is no longer supported, so we can remove BINOP_RANGE too.
This patch is to remove BINOP_RANGE.
gdb:
2014-07-20 Yao Qi <yao@codesourcery.com>
* std-operator.def: Remove BINOP_RANGE.
* breakpoint.c (watchpoint_exp_is_const): Update.
* expprint.c (dump_subexp_body_standard): Likewise.
* eval.c (init_array_element): Remove dead code.
(evaluate_subexp_standard): Likewise.
Chill language support was removed several years ago, and BINOP_IN
isn't used for Pascal. This patch is to remove BINOP_IN.
gdb:
2014-07-20 Yao Qi <yao@codesourcery.com>
* std-operator.def: Remove BINOP_IN.
* breakpoint.c (watchpoint_exp_is_const): Update.
* eval.c (evaluate_subexp_standard): Likewise.
* expprint.c (dump_subexp_body_standard): Likewise.
Even though the opcodes were defined for these instructions,
the actual instruction definitions were lacking.
cpu/
* or1korbis.cpu (l-msync, l-psync, l-csync): New instructions.
opcodes/
* or1k-desc.c, * or1k-desc.h, * or1k-opc.c, * or1k-opc.h,
* or1k-opinst.c: Regenerate.
Prior to version MicroBlaze v8.10.a,EDK 13.1, XMD's gdbserver stub returned 57
registers in response to GDB's G request. Starting with version MicroBlaze
v8.10.a, EDK 13.1, XMD added the slr and shr register, for a count of 59
registers. This patch adds these registers to the expected G response. This patch
fixes the above problem for baremetal and also supports the backward compatibility.
ChangeLog:
2014-07-02 Ajit Agarwal <ajitkum@xilinx.com>
* microblaze-tdep.c (microblaze_register_names): Add
the rshr and rslr register names.
(microblaze_gdbarch_init): Use of tdesc_has_registers.
Use of tdesc_find_feature. Use of tdesc_data_alloc.
Use of tdesc_numbered_register. Use of
microblaze_register_g_packet_guesses. Use of
tdesc_use_registers. Use of set_gdbarch_register_type.
(microblaze_register_g_packet_guesses): New.
* microblaze-tdep.h (microblaze_reg_num): Add
field MICROBLAZE_SLR_REGNUM MICROBLAZE_SHR_REGNUM
MICROBLAZE_NUM_REGS and MICROBLAZE_NUM_CORE_REGS.
(microblaze_frame_cache): Use of MICROBLAZE_NUM_REGS.
* features/microblaze-core.xml: New file.
* features/microblaze-stack-protect.xml: New file.
* features/microblaze-with-stack-protect.c: New file.
* features/microblaze-with-stack-protect.xml: New file.
* features/microblaze.xml: New file.
* features/microblaze.c: New file.
* features/Makefile (microblaze-with-stack-protect): Add
microblaze-with-stack-protect microblaze and
microblaze-expedite.
* regformats/microblaze-with-stack-protect.dat: New file.
* regformats/microblaze.dat: New file.
* doc/gdb.texinfo (MicroBlaze Features): New.
Signed-off-by:Ajit Agarwal ajitkum@xilinx.com
While working on some target stack changes, I noticed that exec_ops is
only used from exec.c. This patch makes it "static". This is cleaner
and makes it simpler to reason about the use of the target.
Tested by rebuilding.
I'm checking this in as obvious.
2014-07-18 Tom Tromey <tromey@redhat.com>
* exec.c (exec_ops): Now static.
* exec.h (exec_ops): Don't declare.
A long time ago Pedro pointed out that there are some calls to
find_target_beneath that pass in an explicit target_ops; but which
should instead use the ops provided to the method in question. See:
https://sourceware.org/ml/gdb-patches/2014-01/msg00429.html
This patch is just a minor cleanup to fix all such calls. There were
only three.
2014-07-18 Tom Tromey <tromey@redhat.com>
* spu-multiarch.c (spu_region_ok_for_hw_watchpoint): Pass "self"
to find_target_beneath.
* ravenscar-thread.c (ravenscar_prepare_to_store): Pass "ops" to
find_target_beneath.
(ravenscar_mourn_inferior): Pass "self" to find_target_beneath.
This fixes PR gdb/17130.
The bug is that some code in utils.c was not updated during the target
delegation change:
if (job_control
/* If there is no terminal switching for this target, then we can't
possibly get screwed by the lack of job control. */
|| current_target.to_terminal_ours == NULL)
fatal ("Quit");
else
fatal ("Quit (expect signal SIGINT when the program is resumed)");
After the delegation change, to_terminal_ours will never be NULL.
I think this bug can be seen before the target delegation change by
enabling target debugging -- this would also cause to_terminal_ours to
be non-NULL.
The fix is to introduce a new target_supports_terminal_ours function,
that properly checks the target stack. This is not perhaps ideal, but
I think is a reasonable-enough approach, and in keeping with some
other existing code of the same form.
This patch also fixes a similar bug in target_supports_delete_record.
2014-07-18 Tom Tromey <tromey@redhat.com>
PR gdb/17130:
* utils.c (quit): Use target_supports_terminal_ours.
* target.h (target_supports_terminal_ours): Declare.
* target.c (target_supports_delete_record): Don't check
to_delete_record against NULL.
(target_supports_terminal_ours): New function.
This patch cleans up some minor inconsistencies in target delegation.
It's primary purpose is to avoid confusion in the code. A few spots
were checking the "beneath" target; however this can only be NULL for
the dummy target, so such tests are not needed. Some other spots were
iterating over the beneath targets, looking for a method
implementation. This is not needed for methods handled by
make-target-delegates, as there is always an implementation.
2014-07-18 Tom Tromey <tromey@redhat.com>
PR gdb/17130:
* spu-multiarch.c (spu_region_ok_for_hw_watchpoint)
(spu_fetch_registers, spu_store_registers, spu_xfer_partial)
(spu_search_memory, spu_mourn_inferior): Simplify delegation.
* linux-thread-db.c (thread_db_pid_to_str): Always delegate.
* windows-nat.c (windows_xfer_partial): Always delegate.
* record-btrace.c (record_btrace_xfer_partial): Simplify
delegation.
(record_btrace_fetch_registers, record_btrace_store_registers)
(record_btrace_prepare_to_store, record_btrace_resume)
(record_btrace_wait, record_btrace_find_new_threads)
(record_btrace_thread_alive): Likewise.
* procfs.c (procfs_xfer_partial): Always delegate.
* corelow.c (core_xfer_partial): Always delegate.
* sol-thread.c (sol_find_new_threads): Simplify delegation.
This patch moves exec_make_note_section a bit earlier in exec.c. This
lets us remove an otherwise unnecessary forward declaration and it
also makes the file a bit more in line with other code, as now
_initialize_exec is the final function in the file.
Tested by rebuilding.
I'm committing this as obvious.
2014-07-18 Tom Tromey <tromey@redhat.com>
* exec.c (exec_make_note_section): Move earlier.
Override the default value of 0x0000 defined in
TEXT_START_ADDR to avoid linux executables to be mapped
at zero page.
ld/
* emulparams/elf32or1k_linux.sh (TEXT_START_ADDR): Increase from
0x0 to first page boundary at 0x2000.
Since we use tkill everywhere, using kill to try to kill each lwp
individually looks suspiciously odd. We should really be using tgkill
everywhere, but at least while we don't get there this makes us
consistent.
gdb/gdbserver/
2014-07-16 Pedro Alves <palves@redhat.com>
* linux-low.c (linux_kill_one_lwp): Use kill_lwp, not kill.
gdb/
2014-07-16 Pedro Alves <palves@redhat.com>
* linux-nat.c (kill_callback): Use kill_lwp, not kill.
I noticed that the existing code casts a function's address to 'long',
but that doesn't work correctly on some ABIs, like Win64, where long
is 32-bit and while pointers are 64-bit:
func_addr = (long) &write_basic_trace_file;
Fixing that showed there's actually another place in the file that
writes a function address to file, and therefore should clear the
Thumb bit. This commit adds a macro+function pair to centralize the
Thumb bit handling, and uses it in both places.
The rest is just enough changes to make the file build without
warnings with "-Wall -Wextra" with x86_64-w64-mingw32-gcc and
i686-w64-mingw32-gcc cross compilers, and with -m32/-m64 on x86_64
GNU/Linux. Currently with x86_64-w64-mingw32-gcc we get:
$ x86_64-w64-mingw32-gcc tfile.c -Wall -DTFILE_DIR=\"\"
tfile.c: In function 'start_trace_file':
tfile.c:51:23: error: 'S_IRGRP' undeclared (first use in this function)
S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);
^
tfile.c:51:23: note: each undeclared identifier is reported only once for each function it appears in
tfile.c:51:31: error: 'S_IROTH' undeclared (first use in this function)
S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);
^
tfile.c: In function 'add_memory_block':
tfile.c:79:10: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
ll_x = (unsigned long) addr;
^
tfile.c: In function 'write_basic_trace_file':
tfile.c:113:15: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
func_addr = (long) &write_basic_trace_file;
^
tfile.c:137:3: warning: passing argument 1 of 'add_memory_block' from incompatible pointer type [enabled by default]
add_memory_block (&testglob, sizeof (testglob));
^
tfile.c:72:1: note: expected 'char *' but argument is of type 'int *'
add_memory_block (char *addr, int size)
^
tfile.c:139:3: warning: passing argument 1 of 'add_memory_block' from incompatible pointer type [enabled by default]
add_memory_block (&testglob2, 1);
^
tfile.c:72:1: note: expected 'char *' but argument is of type 'int *'
add_memory_block (char *addr, int size)
^
tfile.c: In function 'write_error_trace_file':
tfile.c:185:3: warning: implicit declaration of function 'alloca' [-Wimplicit-function-declaration]
char *hex = alloca (len * 2 + 1);
^
tfile.c:185:15: warning: incompatible implicit declaration of built-in function 'alloca' [enabled by default]
char *hex = alloca (len * 2 + 1);
^
tfile.c:211:6: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
(long) &write_basic_trace_file);
^
Tested on x86_64 Fedora 20, -m64 and -m32.
Tested by Yao on arm targets.
gdb/testsuite/
2014-07-16 Pedro Alves <palves@redhat.com>
* gdb.trace/tfile.c: Include unistd.h and stdint.h.
(start_trace_file): Guard S_IRGRP and S_IROTH uses behind #ifdef.
(tfile_write_64, tfile_write_16, tfile_write_8, tfile_write_addr)
(tfile_write_buf): New functions.
(add_memory_block): Rewrite using the above.
(adjust_function_address): New function.
(FUNCTION_ADDRESS): New macro.
(write_basic_trace_file): Remove short_x local, and use
tfile_write_16. Change type of func_addr local to unsigned long
long. Use FUNCTION_ADDRESS instead of handling the Thumb bit
here. Cast argument of add_memory_block to char pointer.
(write_error_trace_file): Avoid alloca. Use FUNCTION_ADDRESS.
(main): Remove parameters.
* gdb.trace/tfile.exp: Remove nowarnings.
Relocations against .got.plt section may not be in the same order as
entries in PLT section. It is incorrect to assume that the Ith reloction
index against .got.plt section always maps to the (I + 1)th entry in PLT
section. This patch matches the .got.plt relocation offset/index in PLT
entry against the index in .got.plt relocation table. It only checks
R_*_JUMP_SLOT and R_*_IRELATIVE relocations. It ignores R_*_TLS_DESC
and R_*_TLSDESC relocations since they have different PLT entries.
bfd/
PR binutils/17154
* elf32-i386.c (elf_i386_plt_sym_val): Only match R_*_JUMP_SLOT
and R_*_IRELATIVE relocation offset with PLT entry.
* elf64-x86-64.c (elf_x86_64_plt_sym_val): Likewise.
(elf_x86_64_plt_sym_val_offset_plt_bnd): New.
(elf_x86_64_get_synthetic_symtab): Use it.
ld/testsuite/
PR binutils/17154
* ld-ifunc/pr17154-i386.d: New file.
* ld-ifunc/pr17154-x86-64.d: Likewise.
* ld-ifunc/pr17154-x86.s: Likewise.
* ld-x86-64/bnd-ifunc-2.d: Likewise.
* ld-x86-64/bnd-ifunc-2.s: Likewise.
* ld-x86-64/mpx.exp: Run bnd-ifunc-2.
* ld-x86-64/tlsdesc-nacl.pd: Updated.
* ld-x86-64/tlsdesc.pd: Likewise.
As Joel pointed out in...
https://sourceware.org/ml/gdb-patches/2014-07/msg00391.html
...it would be nice to add a test for that.
Tested on Linux x86_64 (Ubuntu 14.10).
gdb/testsuite/ChangeLog
2014-07-15 Simon Marchi <simon.marchi@ericsson.com>
* gdb.base/debug-expr.exp: Test string evaluation with
"debug expression" on.
A comment in target.h went past the column limit. This patch
reformats it. I'm pushing this as obvious.
2014-07-16 Tom Tromey <tromey@redhat.com>
* target.h (struct target_ops) <to_delete_record>: Reformat
comment.
target-delegates.c was out of date. This patch rebuilds it.
Built and regtested on x86-64 Fedora 20.
Committed as obvious.
2014-07-16 Tom Tromey <tromey@redhat.com>
* target-delegates.c: Rebuild.
Commit e1f987424b changed how
next_tls_desc_index was set up. This patch updates
elf_i386_compute_jump_table_size to use elf.srelplt->reloc_count
instead of next_tls_desc_index.
bfd/
PR ld/17057
* elf32-i386.c (elf_i386_compute_jump_table_size): Replace
next_tls_desc_index with elf.srelplt->reloc_count.
ld/testsuite/
PR ld/17057
* ld-i386/i386.exp: Run pr17057.
* ld-i386/pr17057.d: New file.
* ld-i386/pr17057.s: Likewise.
The other day I noticed that default_gdb_start reuses the GDB process
if it has been spawned already:
proc default_gdb_start { } {
...
if [info exists gdb_spawn_id] {
return 0
}
I was a bit surprised, and so I hacked in an error to check whether
anything is relying on it:
+ if [info exists gdb_spawn_id] {
+ error "GDB already spawned"
+ }
And lo, that tripped on a funny buglet (see below). The comment in
reread.exp says "Restart GDB entirely", but in reality, due to the
above, that's not what is happening, as a gdb_exit call is missing.
The test is proceeding with the previous GDB process...
I don't really want to go hunt for whether there's an odd setup out
there that assumes this in its board file or something, so for now,
I'm taking the simple route of just making the test do what it says it
does. I think this much makes it an obvious fix.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
(gdb) PASS: gdb.base/reread.exp: run to foo() second time
ERROR: tcl error sourcing ../src/gdb/testsuite/gdb.base/reread.exp.
ERROR: GDB already spawned
while executing
"error "GDB already spawned""
invoked from within
"if [info exists gdb_spawn_id] {
error "GDB already spawned"
}"
(procedure "default_gdb_start" line 22)
invoked from within
"default_gdb_start"
(procedure "gdb_start" line 2)
invoked from within
"gdb_start"
invoked from within
"if [is_remote target] {
unsupported "second pass: GDB should check for changes before running"
} else {
# Put the older executable back in pl..."
(file "../src/gdb/testsuite/gdb.base/reread.exp" line 114)
invoked from within
"source ../src/gdb/testsuite/gdb.base/reread.exp"
("uplevel" body line 1)
invoked from within
"uplevel #0 source ../src/gdb/testsuite/gdb.base/reread.exp"
invoked from within
"catch "uplevel #0 source $test_file_name""
testcase ../src/gdb/testsuite/gdb.base/reread.exp completed in 1 seconds
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
gdb/testsuite/
2014-07-15 Pedro Alves <palves@redhat.com>
* gdb.base/reread.exp: Use clean_restart.
The __flash qualifier is part of the named address spaces for AVR [1]. It
allows putting read-only data in the flash memory, normally reserved for
code.
When used together with a pointer, the DW_AT_address_class attribute is set
to 1 and allows GDB to detect that when it will be dereferenced, the data
will be loaded from the flash memory (with the LPM instruction).
We can now properly debug the following code:
~~~
const __flash char data_in_flash = 0xab;
int
main (void)
{
const __flash char *pointer_to_flash = &data_in_flash;
}
~~~
~~~
(gdb) print pointer_to_flash
$1 = 0x1e8 <data_in_flash> "\253"
(gdb) print/x *pointer_to_flash
$2 = 0xab
(gdb) x/x pointer_to_flash
0x1e8 <data_in_flash>: 0xXXXXXXab
~~~
Whereas previously, GDB would revert to the default address space which is
RAM and mapped in higher memory:
~~~
(gdb) print pointer_to_flash
$1 = 0x8001e8 ""
~~~
[1] https://gcc.gnu.org/onlinedocs/gcc/Named-Address-Spaces.html
2014-07-15 Pierre Langlois <pierre.langlois@embecosm.com>
gdb/
* avr-tdep.c (AVR_TYPE_ADDRESS_CLASS_FLASH): New macro.
(AVR_TYPE_INSTANCE_FLAG_ADDRESS_CLASS_FLASH): Likewise.
(avr_address_to_pointer): Check for AVR_TYPE_ADDRESS_CLASS_FLASH.
(avr_pointer_to_address): Likewise.
(avr_address_class_type_flags): New function.
(avr_address_class_type_flags_to_name): Likewise.
(avr_address_class_name_to_type_flags): Likewise.
(avr_gdbarch_init): Set address_class_type_flags,
address_class_type_flags_to_name and
address_class_name_to_type_flags.
gdb/testsuite/
* gdb.arch/avr-flash-qualifer.c: New.
* gdb.arch/avr-flash-qualifer.exp: New.
The fix that went into GDBserver is also needed on the GDB side.
Although most compilers follow right-to-left evaluation order, the
order of evaluation of a function call's arguments is really
unspecified. target_pid_to_str may well clobber errno when we get to
evaluate the third argument to fprintf_unfiltered.
gdb/
2014-07-15 Pedro Alves <palves@redhat.com>
* linux-nat.c (kill_callback): Save errno and work with saved
copy.
For some reason, OP_STRING is not handled in dump_subexp_body_standard.
This makes the output of "set debug expression 1" very bad when a string
is involved. Example:
(gdb) set debug expression 1
(gdb) print "hello"
... (random garbage, possibly segfault)
This commit handles OP_STRING and skips the appropriate number of exp
elements. The line corresponding to the string now looks like:
0 OP_STRING Language-specific string type: 0
gdb/ChangeLog:
2014-07-15 Simon Marchi <simon.marchi@ericsson.com>
* expprint.c (dump_subexp_body_standard): Handle OP_STRING.
Although most compilers follow right-to-left evaluation order, the
order of evaluation of a function call's arguments is really
unspecified. target_pid_to_str or ptid_of may well clobber errno when
we get to evaluate the third argument to debug_printf.
gdb/gdbserver/
2014-07-15 Pedro Alves <palves@redhat.com>
* linux-low.c (linux_kill_one_lwp): Save errno and work with saved
copy.
gas/
* config/tc-arm.c (add_to_lit_pool): Use "inst.operands[1].imm" for * sign
extension. Casting the type of imm1 and imm2 to offsetT. Fix one logic
error when checking X_op.
Specify -T relocs.ld for emit-relocs-local-addend.d to be consistent
will all other emit-relocs* testcases
ld/testsuite/
* ld-aarch64/emit-relocs-local-addend.d: Use target linker script.
So that we munge isym->st_other once per symbol.
* elflink.c (elf_merge_st_other): Update comments. Simplify
visibility handling. Make isym const. Move code modifying
isym->st_other for --exclude-libs to..
(elf_link_add_object_symbols): ..here.
Put GDB's terminal settings into effect when paginating
gdb/
2014-07-14 Pedro Alves <palves@redhat.com>
* utils.c (prompt_for_continue): Call target_terminal_ours.
gdb/testsuite/
2014-07-14 Pedro Alves <palves@redhat.com>
* gdb.base/paginate-after-ctrl-c-running.c: New file.
* gdb.base/paginate-after-ctrl-c-running.exp: New file.
When the target is resumed in the foreground, we put the inferior's
terminal settings into effect, and remove stdin from the event loop.
When the target stops, we put GDB's terminal settings into effect
again, and re-register stdin in the event loop, ready for user input.
The former is done by target_terminal_inferior, and the latter by
target_terminal_ours.
There's an intermediate -- target_terminal_ours_for_output -- that is
called when printing output related to target events, and we don't
know yet whether we'll stop the program. That puts our terminal
settings into effect, enough to get proper results from our output,
but leaves input wired into the inferior.
If such output paginates, then we need the full target_terminal_ours
in order for the user to be able to provide input to answer the
pagination query.
The test in this commit hangs in async-capable targets without the fix
(as the user/test can't answer the pagination query). It doesn't hang
on sync targets because on those we don't unregister stdin from the
event loop while the target is running (because we block in
target_wait instead of in the event loop in that case).
gdb/
2014-07-14 Pedro Alves <palves@redhat.com>
* utils.c (prompt_for_continue): Call target_terminal_ours.
gdb/testsuite/
2014-07-14 Pedro Alves <palves@redhat.com>
* gdb.base/paginate-after-ctrl-c-running.c: New file.
* gdb.base/paginate-after-ctrl-c-running.exp: New file.
If an error is thrown while handling a target event (within
fetch_inferior_event), and, the interpreter is not async (but the
target is), then GDB prints the prompt twice.
One way to see that in action is throw a QUIT while in a pagination
prompt issued from within fetch_inferior_event (or one of its
callees). E.g. from the test:
---Type <return> to continue, or q <return> to quit---
^CQuit
(gdb) (gdb) p 1
^^^^^^^^^^^
$1 = 1
(gdb)
The issue is that inferior_event_handler swallows errors and notifies
the observers (the interpreters) about the command error, even if the
interpreter is forced sync while we're handling a nested event loop
(for execute_command). The observers print a prompt, and then when we
get back to the top event loop, we print another (in
start_event_loop).
I see no reason the error should be swallowed here. Just cancel the
execution related bits and let the error propagate to the top level
(start_event_loop), which re-enables stdin and notifies observers.
gdb/
2014-07-14 Pedro Alves <palves@redhat.com>
* inf-loop.c (inferior_event_handler): Use TRY_CATCH instead of
catch_errors. Don't re-enable stdin or notify observers where,
and rethrow error.
(fetch_inferior_event_wrapper): Delete.
gdb/testsuite/
2014-07-14 Pedro Alves <palves@redhat.com>
* gdb.base/double-prompt-target-event-error.c: New file.
* gdb.base/double-prompt-target-event-error.exp: New file.
If a pagination prompt triggers while the target is running, and the
target exits before the user responded to the pagination query, this
happens:
Starting program: foo
---Type <return> to continue, or q <return> to quit---No unwaited-for children left.
Couldn't get registers: No such process.
Couldn't get registers: No such process.
Couldn't get registers: No such process.
(gdb) Couldn't get registers: No such process.
(gdb)
To reiterate, the user hasn't replied to the pagination prompt above.
A pagination query nests an event loop (in gdb_readline_wrapper). In
async mode, in addition to stdin and signal handlers, we'll have the
target also installed in the event loop still. So if the target
reports an event, that wakes up the nested event loop, which calls
into fetch_inferior_event etc. to handle the event which generates
further output, all while we should be waiting for pagination
confirmation...
(TBC, any target event that generates output ends up spuriously waking
up the pagination, though exits seem to be the worse kind.)
I've played with a couple different approaches to fixing this, while
at the same time trying to avoid being invasive. Both revolve around
not listening to target events while in a pagination prompt (doing
anything else I think would be a much bigger change).
The approach taken just removes the target from the event loop while
within gdb_readline_wrapper. The other approach used gdb_select
directly, with only input_fd installed, but that had the issue that it
didn't handle the async signal handlers, and turned out to be a bit
more code than the first version.
gdb/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* top.c: Include "inf-loop.h".
(struct gdb_readline_wrapper_cleanup) <target_is_async_orig>: New
field.
(gdb_readline_wrapper_cleanup): Make the target async again, if it
was async before.
(gdb_readline_wrapper): Store whether the target is async, and
make it sync.
gdb/testsuite/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* gdb.base/paginate-inferior-exit.c: New file.
* gdb.base/paginate-inferior-exit.exp: New file.
If pagination occurs as result of output sent as response to a target
event while the target is executing in the background, subsequent
input aborts readline/gdb:
$ gdb program
...
(gdb) continue&
Continuing.
(gdb)
---Type <return> to continue, or q <return> to quit---
*return*
---Type <return> to continue, or q <return> to quit---
Breakpoint 2, after_sleep () at paginate-bg-execution.c:21
---Type <return> to continue, or q <return> to quit---
21 return; /* after sleep */
p 1
readline: readline_callback_read_char() called with no handler!
*abort/SIGABRT*
$
gdb_readline_wrapper_line removes the handler after a line is
processed. Usually, we'll end up re-displaying the prompt, and that
reinstalls the handler. But if the output is coming out of handling
a stop event, we don't re-display the prompt, and nothing restores the
handler. So the next input wakes up the event loop and calls into
readline, which aborts.
We should do better with the prompt handling while the target is
running (I think we should coordinate with readline, and
hide/redisplay it around output), but that's a more invasive change
better done post 7.8, so this patch is conservative and just
reinstalls the handler as soon as we're out of the readline line
callback.
gdb/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* top.c (gdb_readline_wrapper_line): Tweak comment.
(gdb_readline_wrapper_cleanup): If readline is enabled, reinstall
the input handler callback.
gdb/testsuite/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* gdb.base/paginate-bg-execution.c: New file.
* gdb.base/paginate-bg-execution.exp: New file.
This fixes:
$ ./gdb program -ex "set height 2" -ex "start"
...
Reading symbols from /home/pedro/gdb/tests/threads...done.
---Type <return> to continue, or q <return> to quit---^CQuit << ctrl-c triggers a Quit
*type something*
readline: readline_callback_read_char() called with no handler!
Aborted
$
Usually, if an error propagates all the way to the top level, we'll
re-enable stdin, in case the command that was running was a
synchronous command. That's done in the event loop's actual loop
(event-loop.c:start_event_loop). However, if a foreground execution
command is run before the event loop starts and throws, nothing is
presently reenabling stdin, which leaves sync_execution set.
When we do start the event loop, because sync_execution is still
(mistakenly) set, display_gdb_prompt removes the readline input
callback, even though stdin is registered in the event loop. Any
input from here on results in readline aborting.
Such commands are run through catch_command_errors,
catch_command_errors_const, so add the tweak there.
gdb/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* main.c: Include event-top.h.
(handle_command_errors): New function.
(catch_command_errors, catch_command_errors_const): Use it.
gdb/testsuite/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* gdb.base/paginate-execution-startup.c: New file.
* gdb.base/paginate-execution-startup.exp: New file.
* lib/gdb.exp (pagination_prompt): New global.
(default_gdb_spawn): New procedure, factored out from
default_gdb_spawn.
(default_gdb_start): Adjust to call default_gdb_spawn.
(gdb_spawn): New procedure.
Often we'll do something like:
if {$ok} {
fail "whatever"
} else {
pass "whatever"
}
This adds a helper procedure for that, and converts one random place
to use it, as an example.
2014-07-14 Pedro Alves <palves@redhat.com>
* lib/gdb.exp (gdb_assert): New procedure.
* gdb.trace/backtrace.exp (gdb_backtrace_tdp_4): Use it.
We'll need to add error handling code to commands run before the event
loop starts (commands in .gdbinit, -ex commands, etc.). Turns out
those are run through catch_command_errors, and, catch_command_errors
is used nowhere else. Move it (and the _const variant) to main.c, so
that we can further specialize it freely.
gdb/
2014-07-14 Pedro Alves <palves@redhat.com>
* exceptions.c (catch_command_errors, catch_command_errors_const):
Moved to main.c.
* exceptions.h (catch_command_errors_ftype)
(catch_command_errors_const_ftype): Moved to main.c.
(catch_command_errors, catch_command_errors_const): Delete
declarations.
* main.c (catch_command_errors_ftype)
(catch_command_errors_const_ftype): Moved here from exceptions.h.
(catch_command_errors, catch_command_errors_const)): Moved here
from exceptions.c and make static.
