binutils-gdb/gdb/testsuite/gdb.base/bp-permanent.exp

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# Copyright (C) 2014-2017 Free Software Foundation, Inc.
fix skipping permanent breakpoints The gdb.arch/i386-bp_permanent.exp test is currently failing an assertion recently added: (gdb) stepi ../../src/gdb/infrun.c:2237: internal-error: resume: Assertion `sig != GDB_SIGNAL_0' failed. A problem internal to GDB has been detected, further debugging may prove unreliable. Quit this debugging session? (y or n) FAIL: gdb.arch/i386-bp_permanent.exp: Single stepping past permanent breakpoint. (GDB internal error) The assertion expects that the only reason we currently need to step a breakpoint instruction is when we have a signal to deliver. But when stepping a permanent breakpoint (with or without a signal) we also reach this code. The assertion is correct and the permanent breakpoints skipping code is wrong. Consider the case of the user doing "step/stepi" when stopped at a permanent breakpoint. GDB's `resume' calls the gdbarch_skip_permanent_breakpoint hook and then happily continues stepping: /* Normally, by the time we reach `resume', the breakpoints are either removed or inserted, as appropriate. The exception is if we're sitting at a permanent breakpoint; we need to step over it, but permanent breakpoints can't be removed. So we have to test for it here. */ if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here) { gdbarch_skip_permanent_breakpoint (gdbarch, regcache); } But since gdbarch_skip_permanent_breakpoint already advanced the PC manually, this ends up executing the instruction that is _after_ the breakpoint instruction. The user-visible result is that a single-step steps two instructions. The gdb.arch/i386-bp_permanent.exp test is actually ensuring that that's indeed how things work. It runs to an int3 instruction, does "stepi", and checks that "leave" was executed with that "stepi". Like this: (gdb) b *0x0804848c Breakpoint 2 at 0x804848c (gdb) c Continuing. Breakpoint 2, 0x0804848c in standard () (gdb) disassemble Dump of assembler code for function standard: 0x08048488 <+0>: push %ebp 0x08048489 <+1>: mov %esp,%ebp 0x0804848b <+3>: push %edi => 0x0804848c <+4>: int3 0x0804848d <+5>: leave 0x0804848e <+6>: ret 0x0804848f <+7>: nop (gdb) si 0x0804848e in standard () (gdb) disassemble Dump of assembler code for function standard: 0x08048488 <+0>: push %ebp 0x08048489 <+1>: mov %esp,%ebp 0x0804848b <+3>: push %edi 0x0804848c <+4>: int3 0x0804848d <+5>: leave => 0x0804848e <+6>: ret 0x0804848f <+7>: nop End of assembler dump. (gdb) One would instead expect that a stepi at 0x0804848c stops at 0x0804848d, _before_ the "leave" is executed. This commit changes GDB this way. Care is taken to make stepping into a signal handler when the step starts at a permanent breakpoint instruction work correctly. The patch adjusts gdb.arch/i386-bp_permanent.exp in this direction, and also makes it work on x86_64 (currently it only works on i*86). The patch also adds a new gdb.base/bp-permanent.exp test that exercises many different code paths related to stepping permanent breakpoints, including the stepping with signals cases. The test uses "hack/trick" to make it work on all (or most) platforms -- it doesn't really hard code a breakpoint instruction. Tested on x86_64 Fedora 20, native and gdbserver. gdb/ 2014-11-12 Pedro Alves <palves@redhat.com> * infrun.c (resume): Clear the thread's 'stepped_breakpoint' flag. Rewrite stepping over a permanent breakpoint. (thread_still_needs_step_over, proceed): Don't set stepping_over_breakpoint for permanent breakpoints. (handle_signal_stop): Don't clear stepped_breakpoint. Also pull single-step breakpoints out of the target on hardware step targets. (process_event_stop_test): If stepping a permanent breakpoint doesn't hit the step-resume breakpoint, delete the step-resume breakpoint. (switch_back_to_stepped_thread): Also check if the stepped thread has advanced already on hardware step targets. (currently_stepping): Return true if the thread stepped a breakpoint. gdb/testsuite/ 2014-11-12 Pedro Alves <palves@redhat.com> * gdb.arch/i386-bp_permanent.c: New file. * gdb.arch/i386-bp_permanent.exp: Don't skip on x86_64. (srcfile): Set to i386-bp_permanent.c. (top level): Adjust to work in both 32-bit and 64-bit modes. Test that stepi does not execute the 'leave' instruction, instead of testing it does execute. * gdb.base/bp-permanent.c: New file. * gdb.base/bp-permanent.exp: New file.
2014-11-12 11:10:49 +01:00
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
# This file is part of the gdb testsuite.
# Test stepping over permanent breakpoints.
standard_testfile
set options { debug }
if { ![target_info exists gdb,nosignals] } {
lappend options "additional_flags=-DSIGNALS"
}
if {[build_executable "failed to prepare" $testfile $srcfile $options]} {
return -1
}
set line_bp [gdb_get_line_number "write permanent bp"]
# The test proper. ALWAYS_INSERTED indicates whether testing in
# "breakpoint always-inserted" mode. If SW_WATCHPOINT is true, set a
# software watchpoint, which forces constantly single-stepping, and
# exercises stepping the permanent breakpoint while delivering a
# signal at the same time.
proc test {always_inserted sw_watchpoint} {
global line_bp
global hex decimal
global gdb_prompt
global srcfile binfile
clean_restart $binfile
if ![runto_main] then {
return -1
}
gdb_test "set breakpoint always-inserted $always_inserted"
if {$sw_watchpoint} {
# Watching a convenience variable forces a software
# watchpoint.
gdb_test "watch \$dummy_convenience" "Watchpoint .*"
}
set address_bp ""
set address_after_bp ""
with_test_prefix "setup" {
# Set a breakpoint where we'll manually plant a permanent
# breakpoint.
set test "set probe breakpoint"
gdb_test_multiple "break $line_bp" $test {
-re "Breakpoint .* at ($hex).*$gdb_prompt $" {
set address_bp $expect_out(1,string)
pass $test
}
}
if {$address_bp == ""} {
return
}
# Get the size of the instruction where the breakpoint will
# manually inserted.
set test "get size of instruction"
gdb_test_multiple "x/2i $address_bp" $test {
-re ".*$hex <test\\+$decimal>:\[^\r\n\]+\r\n\[ \]+($hex).*\.\r\n$gdb_prompt $" {
set address_after_bp $expect_out(1,string)
pass $test
}
}
if {$address_after_bp == ""} {
return
}
# Write address range where the breakpoint is inserted to the
# corresponding variables in the inferior.
gdb_test "p /x addr_bp = $address_bp" " = $address_bp" \
"write addr_bp"
gdb_test "p /x addr_after_bp = $address_after_bp" " = $address_after_bp" \
"write addr_after_bp"
# Run the "setup" function in the inferior. This memcpy's the
# breakpoint instruction to a buffer in the inferior.
gdb_test "next" "test_basics \\(\\).*" "next over setup"
fix skipping permanent breakpoints The gdb.arch/i386-bp_permanent.exp test is currently failing an assertion recently added: (gdb) stepi ../../src/gdb/infrun.c:2237: internal-error: resume: Assertion `sig != GDB_SIGNAL_0' failed. A problem internal to GDB has been detected, further debugging may prove unreliable. Quit this debugging session? (y or n) FAIL: gdb.arch/i386-bp_permanent.exp: Single stepping past permanent breakpoint. (GDB internal error) The assertion expects that the only reason we currently need to step a breakpoint instruction is when we have a signal to deliver. But when stepping a permanent breakpoint (with or without a signal) we also reach this code. The assertion is correct and the permanent breakpoints skipping code is wrong. Consider the case of the user doing "step/stepi" when stopped at a permanent breakpoint. GDB's `resume' calls the gdbarch_skip_permanent_breakpoint hook and then happily continues stepping: /* Normally, by the time we reach `resume', the breakpoints are either removed or inserted, as appropriate. The exception is if we're sitting at a permanent breakpoint; we need to step over it, but permanent breakpoints can't be removed. So we have to test for it here. */ if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here) { gdbarch_skip_permanent_breakpoint (gdbarch, regcache); } But since gdbarch_skip_permanent_breakpoint already advanced the PC manually, this ends up executing the instruction that is _after_ the breakpoint instruction. The user-visible result is that a single-step steps two instructions. The gdb.arch/i386-bp_permanent.exp test is actually ensuring that that's indeed how things work. It runs to an int3 instruction, does "stepi", and checks that "leave" was executed with that "stepi". Like this: (gdb) b *0x0804848c Breakpoint 2 at 0x804848c (gdb) c Continuing. Breakpoint 2, 0x0804848c in standard () (gdb) disassemble Dump of assembler code for function standard: 0x08048488 <+0>: push %ebp 0x08048489 <+1>: mov %esp,%ebp 0x0804848b <+3>: push %edi => 0x0804848c <+4>: int3 0x0804848d <+5>: leave 0x0804848e <+6>: ret 0x0804848f <+7>: nop (gdb) si 0x0804848e in standard () (gdb) disassemble Dump of assembler code for function standard: 0x08048488 <+0>: push %ebp 0x08048489 <+1>: mov %esp,%ebp 0x0804848b <+3>: push %edi 0x0804848c <+4>: int3 0x0804848d <+5>: leave => 0x0804848e <+6>: ret 0x0804848f <+7>: nop End of assembler dump. (gdb) One would instead expect that a stepi at 0x0804848c stops at 0x0804848d, _before_ the "leave" is executed. This commit changes GDB this way. Care is taken to make stepping into a signal handler when the step starts at a permanent breakpoint instruction work correctly. The patch adjusts gdb.arch/i386-bp_permanent.exp in this direction, and also makes it work on x86_64 (currently it only works on i*86). The patch also adds a new gdb.base/bp-permanent.exp test that exercises many different code paths related to stepping permanent breakpoints, including the stepping with signals cases. The test uses "hack/trick" to make it work on all (or most) platforms -- it doesn't really hard code a breakpoint instruction. Tested on x86_64 Fedora 20, native and gdbserver. gdb/ 2014-11-12 Pedro Alves <palves@redhat.com> * infrun.c (resume): Clear the thread's 'stepped_breakpoint' flag. Rewrite stepping over a permanent breakpoint. (thread_still_needs_step_over, proceed): Don't set stepping_over_breakpoint for permanent breakpoints. (handle_signal_stop): Don't clear stepped_breakpoint. Also pull single-step breakpoints out of the target on hardware step targets. (process_event_stop_test): If stepping a permanent breakpoint doesn't hit the step-resume breakpoint, delete the step-resume breakpoint. (switch_back_to_stepped_thread): Also check if the stepped thread has advanced already on hardware step targets. (currently_stepping): Return true if the thread stepped a breakpoint. gdb/testsuite/ 2014-11-12 Pedro Alves <palves@redhat.com> * gdb.arch/i386-bp_permanent.c: New file. * gdb.arch/i386-bp_permanent.exp: Don't skip on x86_64. (srcfile): Set to i386-bp_permanent.c. (top level): Adjust to work in both 32-bit and 64-bit modes. Test that stepi does not execute the 'leave' instruction, instead of testing it does execute. * gdb.base/bp-permanent.c: New file. * gdb.base/bp-permanent.exp: New file.
2014-11-12 11:10:49 +01:00
delete_breakpoints
# We now have the breakpoint instruction stored in 'buffer'. Poke it
# to memory manually.
set count [expr $address_after_bp - $address_bp]
for {set i 0} {$i < $count} {incr i} {
set test "p /x addr_bp\[$i\] = buffer\[$i\]"
gdb_test_multiple $test $test {
-re "Cannot access memory at address $hex.*$gdb_prompt $" {
# Some targets (QEMU for one) will disallow writes to the
# .text section under certain circumstances. It is no use
# continuing with the test at this point. Just return.
Fix test names starting with uppercase output by basic functions The following patch is based on the previous patch i sent and handles cases of test names that start with an uppercase letter. Test names should start with lowercase unless it starts with the name of a technology, architecture, ISA etc. This first patch addresses cases of test names output explicitly via xfail, kfail, kpass, fail, pass, unsupported, untested and also names set with the pattern "set test" and "set testname". gdb/testsuite/ChangeLog: 2016-12-01 Luis Machado <lgustavo@codesourcery.com> Fix test names starting with uppercase throughout all the files below. * gdb.ada/array_return.exp * gdb.ada/catch_ex.exp * gdb.ada/info_exc.exp * gdb.ada/mi_catch_ex.exp * gdb.ada/mi_dyn_arr.exp * gdb.ada/mi_ex_cond.exp * gdb.ada/mi_exc_info.exp * gdb.ada/mi_interface.exp * gdb.ada/mi_task_arg.exp * gdb.ada/mi_task_info.exp * gdb.ada/mi_var_array.exp * gdb.arch/alpha-step.exp * gdb.arch/amd64-disp-step.exp * gdb.arch/arm-disp-step.exp * gdb.arch/disp-step-insn-reloc.exp * gdb.arch/e500-prologue.exp * gdb.arch/ftrace-insn-reloc.exp * gdb.arch/gdb1558.exp * gdb.arch/i386-bp_permanent.exp * gdb.arch/i386-disp-step.exp * gdb.arch/i386-float.exp * gdb.arch/i386-gnu-cfi.exp * gdb.arch/ia64-breakpoint-shadow.exp * gdb.arch/mips16-thunks.exp * gdb.arch/pa-nullify.exp * gdb.arch/powerpc-aix-prologue.exp * gdb.arch/powerpc-power.exp * gdb.arch/ppc-dfp.exp * gdb.arch/s390-tdbregs.exp * gdb.arch/spu-info.exp * gdb.arch/spu-ls.exp * gdb.arch/thumb-bx-pc.exp * gdb.base/advance.exp * gdb.base/annota-input-while-running.exp * gdb.base/arrayidx.exp * gdb.base/asmlabel.exp * gdb.base/async.exp * gdb.base/attach-wait-input.exp * gdb.base/auto-connect-native-target.exp * gdb.base/batch-preserve-term-settings.exp * gdb.base/bfp-test.exp * gdb.base/bigcore.exp * gdb.base/bp-permanent.exp * gdb.base/break-always.exp * gdb.base/break-fun-addr.exp * gdb.base/break-idempotent.exp * gdb.base/break-main-file-remove-fail.exp * gdb.base/break-probes.exp * gdb.base/break-unload-file.exp * gdb.base/break.exp * gdb.base/call-ar-st.exp * gdb.base/call-rt-st.exp * gdb.base/call-sc.exp * gdb.base/call-signal-resume.exp * gdb.base/call-strs.exp * gdb.base/callexit.exp * gdb.base/callfuncs.exp * gdb.base/catch-gdb-caused-signals.exp * gdb.base/catch-signal-siginfo-cond.exp * gdb.base/catch-syscall.exp * gdb.base/compare-sections.exp * gdb.base/cond-eval-mode.exp * gdb.base/condbreak-call-false.exp * gdb.base/consecutive-step-over.exp * gdb.base/cursal.exp * gdb.base/disabled-location.exp * gdb.base/disasm-end-cu.exp * gdb.base/display.exp * gdb.base/double-prompt-target-event-error.exp * gdb.base/dprintf-bp-same-addr.exp * gdb.base/dprintf-detach.exp * gdb.base/dprintf-next.exp * gdb.base/dprintf-non-stop.exp * gdb.base/dprintf-pending.exp * gdb.base/dso2dso.exp * gdb.base/ending-run.exp * gdb.base/enum_cond.exp * gdb.base/examine-backward.exp * gdb.base/exe-lock.exp * gdb.base/exec-invalid-sysroot.exp * gdb.base/execl-update-breakpoints.exp * gdb.base/execution-termios.exp * gdb.base/fileio.exp * gdb.base/fixsection.exp * gdb.base/foll-exec-mode.exp * gdb.base/foll-exec.exp * gdb.base/fork-running-state.exp * gdb.base/frame-args.exp * gdb.base/fullpath-expand.exp * gdb.base/func-ptr.exp * gdb.base/gcore-relro-pie.exp * gdb.base/gdb1090.exp * gdb.base/gdb1555.exp * gdb.base/global-var-nested-by-dso.exp * gdb.base/gnu-ifunc.exp * gdb.base/hbreak-in-shr-unsupported.exp * gdb.base/hbreak-unmapped.exp * gdb.base/hook-stop.exp * gdb.base/infcall-input.exp * gdb.base/info-fun.exp * gdb.base/info-shared.exp * gdb.base/interrupt-noterm.exp * gdb.base/jit-so.exp * gdb.base/jit.exp * gdb.base/line-symtabs.exp * gdb.base/list.exp * gdb.base/longjmp.exp * gdb.base/macscp.exp * gdb.base/max-value-size.exp * gdb.base/nodebug.exp * gdb.base/nofield.exp * gdb.base/overlays.exp * gdb.base/paginate-after-ctrl-c-running.exp * gdb.base/paginate-bg-execution.exp * gdb.base/paginate-inferior-exit.exp * gdb.base/pending.exp * gdb.base/pr11022.exp * gdb.base/printcmds.exp * gdb.base/ptr-typedef.exp * gdb.base/ptype.exp * gdb.base/randomize.exp * gdb.base/range-stepping.exp * gdb.base/realname-expand.exp * gdb.base/relativedebug.exp * gdb.base/remote.exp * gdb.base/savedregs.exp * gdb.base/sepdebug.exp * gdb.base/set-noassign.exp * gdb.base/shlib-call.exp * gdb.base/shreloc.exp * gdb.base/sigaltstack.exp * gdb.base/sigbpt.exp * gdb.base/siginfo-addr.exp * gdb.base/siginfo-obj.exp * gdb.base/siginfo-thread.exp * gdb.base/signest.exp * gdb.base/signull.exp * gdb.base/sigrepeat.exp * gdb.base/skip.exp * gdb.base/so-impl-ld.exp * gdb.base/solib-corrupted.exp * gdb.base/solib-disc.exp * gdb.base/solib-display.exp * gdb.base/solib-overlap.exp * gdb.base/solib-search.exp * gdb.base/solib-symbol.exp * gdb.base/source-execution.exp * gdb.base/sss-bp-on-user-bp-2.exp * gdb.base/sss-bp-on-user-bp.exp * gdb.base/stack-checking.exp * gdb.base/stale-infcall.exp * gdb.base/step-break.exp * gdb.base/step-line.exp * gdb.base/step-over-exit.exp * gdb.base/step-test.exp * gdb.base/structs.exp * gdb.base/sym-file.exp * gdb.base/symtab-search-order.exp * gdb.base/term.exp * gdb.base/type-opaque.exp * gdb.base/unload.exp * gdb.base/until-nodebug.exp * gdb.base/until.exp * gdb.base/unwindonsignal.exp * gdb.base/watch-cond.exp * gdb.base/watch-non-mem.exp * gdb.base/watch_thread_num.exp * gdb.base/watchpoint-reuse-slot.exp * gdb.base/watchpoint-solib.exp * gdb.base/watchpoint.exp * gdb.btrace/dlopen.exp * gdb.cell/arch.exp * gdb.cell/break.exp * gdb.cell/bt.exp * gdb.cell/core.exp * gdb.cell/data.exp * gdb.cell/dwarfaddr.exp * gdb.cell/ea-cache.exp * gdb.cell/ea-standalone.exp * gdb.cell/ea-test.exp * gdb.cell/f-regs.exp * gdb.cell/fork.exp * gdb.cell/gcore.exp * gdb.cell/mem-access.exp * gdb.cell/ptype.exp * gdb.cell/registers.exp * gdb.cell/sizeof.exp * gdb.cell/solib-symbol.exp * gdb.cell/solib.exp * gdb.compile/compile-tls.exp * gdb.cp/exception.exp * gdb.cp/gdb2495.exp * gdb.cp/local.exp * gdb.cp/mb-inline.exp * gdb.cp/mb-templates.exp * gdb.cp/pr10687.exp * gdb.cp/pr9167.exp * gdb.cp/scope-err.exp * gdb.cp/templates.exp * gdb.cp/virtfunc.exp * gdb.dwarf2/dw2-dir-file-name.exp * gdb.dwarf2/dw2-single-line-discriminators.exp * gdb.fortran/complex.exp * gdb.fortran/library-module.exp * gdb.guile/guile.exp * gdb.guile/scm-cmd.exp * gdb.guile/scm-frame-inline.exp * gdb.guile/scm-objfile.exp * gdb.guile/scm-pretty-print.exp * gdb.guile/scm-symbol.exp * gdb.guile/scm-type.exp * gdb.guile/scm-value.exp * gdb.linespec/keywords.exp * gdb.linespec/ls-errs.exp * gdb.linespec/macro-relative.exp * gdb.linespec/thread.exp * gdb.mi/mi-breakpoint-changed.exp * gdb.mi/mi-dprintf-pending.exp * gdb.mi/mi-fullname-deleted.exp * gdb.mi/mi-logging.exp * gdb.mi/mi-pending.exp * gdb.mi/mi-solib.exp * gdb.mi/new-ui-mi-sync.exp * gdb.mi/user-selected-context-sync.exp * gdb.multi/dummy-frame-restore.exp * gdb.multi/multi-arch-exec.exp * gdb.multi/remove-inferiors.exp * gdb.multi/watchpoint-multi-exit.exp * gdb.opt/solib-intra-step.exp * gdb.perf/backtrace.exp * gdb.perf/single-step.exp * gdb.perf/skip-command.exp * gdb.perf/skip-prologue.exp * gdb.perf/solib.exp * gdb.python/lib-types.exp * gdb.python/py-as-string.exp * gdb.python/py-bad-printers.exp * gdb.python/py-block.exp * gdb.python/py-breakpoint.exp * gdb.python/py-cmd.exp * gdb.python/py-events.exp * gdb.python/py-evthreads.exp * gdb.python/py-finish-breakpoint.exp * gdb.python/py-finish-breakpoint2.exp * gdb.python/py-frame-inline.exp * gdb.python/py-frame.exp * gdb.python/py-inferior.exp * gdb.python/py-infthread.exp * gdb.python/py-mi.exp * gdb.python/py-objfile.exp * gdb.python/py-pp-maint.exp * gdb.python/py-pp-registration.exp * gdb.python/py-prettyprint.exp * gdb.python/py-recurse-unwind.exp * gdb.python/py-shared.exp * gdb.python/py-symbol.exp * gdb.python/py-symtab.exp * gdb.python/py-template.exp * gdb.python/py-type.exp * gdb.python/py-unwind-maint.exp * gdb.python/py-unwind.exp * gdb.python/py-value.exp * gdb.python/python.exp * gdb.reverse/finish-reverse-bkpt.exp * gdb.reverse/insn-reverse.exp * gdb.reverse/next-reverse-bkpt-over-sr.exp * gdb.reverse/solib-precsave.exp * gdb.reverse/solib-reverse.exp * gdb.stabs/gdb11479.exp * gdb.stabs/weird.exp * gdb.threads/fork-child-threads.exp * gdb.threads/fork-plus-threads.exp * gdb.threads/fork-thread-pending.exp * gdb.threads/forking-threads-plus-breakpoint.exp * gdb.threads/hand-call-in-threads.exp * gdb.threads/interrupted-hand-call.exp * gdb.threads/linux-dp.exp * gdb.threads/local-watch-wrong-thread.exp * gdb.threads/next-while-other-thread-longjmps.exp * gdb.threads/non-ldr-exit.exp * gdb.threads/pending-step.exp * gdb.threads/print-threads.exp * gdb.threads/process-dies-while-detaching.exp * gdb.threads/process-dies-while-handling-bp.exp * gdb.threads/pthreads.exp * gdb.threads/queue-signal.exp * gdb.threads/reconnect-signal.exp * gdb.threads/signal-command-handle-nopass.exp * gdb.threads/signal-command-multiple-signals-pending.exp * gdb.threads/signal-delivered-right-thread.exp * gdb.threads/signal-sigtrap.exp * gdb.threads/sigthread.exp * gdb.threads/staticthreads.exp * gdb.threads/stepi-random-signal.exp * gdb.threads/thread-unwindonsignal.exp * gdb.threads/thread_check.exp * gdb.threads/thread_events.exp * gdb.threads/tid-reuse.exp * gdb.threads/tls-nodebug.exp * gdb.threads/tls-shared.exp * gdb.threads/tls-so_extern.exp * gdb.threads/tls.exp * gdb.threads/wp-replication.exp * gdb.trace/actions-changed.exp * gdb.trace/actions.exp * gdb.trace/backtrace.exp * gdb.trace/change-loc.exp * gdb.trace/collection.exp * gdb.trace/deltrace.exp * gdb.trace/disconnected-tracing.exp * gdb.trace/entry-values.exp * gdb.trace/ftrace-lock.exp * gdb.trace/ftrace.exp * gdb.trace/infotrace.exp * gdb.trace/mi-trace-frame-collected.exp * gdb.trace/mi-trace-unavailable.exp * gdb.trace/mi-traceframe-changed.exp * gdb.trace/mi-tracepoint-changed.exp * gdb.trace/mi-tsv-changed.exp * gdb.trace/no-attach-trace.exp * gdb.trace/packetlen.exp * gdb.trace/passc-dyn.exp * gdb.trace/passcount.exp * gdb.trace/pending.exp * gdb.trace/pr16508.exp * gdb.trace/qtro.exp * gdb.trace/range-stepping.exp * gdb.trace/read-memory.exp * gdb.trace/report.exp * gdb.trace/save-trace.exp * gdb.trace/signal.exp * gdb.trace/stap-trace.exp * gdb.trace/status-stop.exp * gdb.trace/strace.exp * gdb.trace/tfile.exp * gdb.trace/tfind.exp * gdb.trace/trace-break.exp * gdb.trace/trace-condition.exp * gdb.trace/trace-enable-disable.exp * gdb.trace/trace-mt.exp * gdb.trace/tracecmd.exp * gdb.trace/tracefile-pseudo-reg.exp * gdb.trace/tspeed.exp * gdb.trace/tstatus.exp * gdb.trace/tsv.exp * gdb.trace/unavailable.exp * gdb.trace/while-dyn.exp * gdb.trace/while-stepping.exp * lib/gdb-guile.exp * lib/gdb.exp * lib/mi-support.exp * lib/pascal.exp * lib/perftest.exp * lib/prelink-support.exp * lib/selftest-support.exp
2016-12-01 21:40:05 +01:00
unsupported "cannot modify memory"
return
}
-re " = .*$gdb_prompt $" {
pass $test
}
}
fix skipping permanent breakpoints The gdb.arch/i386-bp_permanent.exp test is currently failing an assertion recently added: (gdb) stepi ../../src/gdb/infrun.c:2237: internal-error: resume: Assertion `sig != GDB_SIGNAL_0' failed. A problem internal to GDB has been detected, further debugging may prove unreliable. Quit this debugging session? (y or n) FAIL: gdb.arch/i386-bp_permanent.exp: Single stepping past permanent breakpoint. (GDB internal error) The assertion expects that the only reason we currently need to step a breakpoint instruction is when we have a signal to deliver. But when stepping a permanent breakpoint (with or without a signal) we also reach this code. The assertion is correct and the permanent breakpoints skipping code is wrong. Consider the case of the user doing "step/stepi" when stopped at a permanent breakpoint. GDB's `resume' calls the gdbarch_skip_permanent_breakpoint hook and then happily continues stepping: /* Normally, by the time we reach `resume', the breakpoints are either removed or inserted, as appropriate. The exception is if we're sitting at a permanent breakpoint; we need to step over it, but permanent breakpoints can't be removed. So we have to test for it here. */ if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here) { gdbarch_skip_permanent_breakpoint (gdbarch, regcache); } But since gdbarch_skip_permanent_breakpoint already advanced the PC manually, this ends up executing the instruction that is _after_ the breakpoint instruction. The user-visible result is that a single-step steps two instructions. The gdb.arch/i386-bp_permanent.exp test is actually ensuring that that's indeed how things work. It runs to an int3 instruction, does "stepi", and checks that "leave" was executed with that "stepi". Like this: (gdb) b *0x0804848c Breakpoint 2 at 0x804848c (gdb) c Continuing. Breakpoint 2, 0x0804848c in standard () (gdb) disassemble Dump of assembler code for function standard: 0x08048488 <+0>: push %ebp 0x08048489 <+1>: mov %esp,%ebp 0x0804848b <+3>: push %edi => 0x0804848c <+4>: int3 0x0804848d <+5>: leave 0x0804848e <+6>: ret 0x0804848f <+7>: nop (gdb) si 0x0804848e in standard () (gdb) disassemble Dump of assembler code for function standard: 0x08048488 <+0>: push %ebp 0x08048489 <+1>: mov %esp,%ebp 0x0804848b <+3>: push %edi 0x0804848c <+4>: int3 0x0804848d <+5>: leave => 0x0804848e <+6>: ret 0x0804848f <+7>: nop End of assembler dump. (gdb) One would instead expect that a stepi at 0x0804848c stops at 0x0804848d, _before_ the "leave" is executed. This commit changes GDB this way. Care is taken to make stepping into a signal handler when the step starts at a permanent breakpoint instruction work correctly. The patch adjusts gdb.arch/i386-bp_permanent.exp in this direction, and also makes it work on x86_64 (currently it only works on i*86). The patch also adds a new gdb.base/bp-permanent.exp test that exercises many different code paths related to stepping permanent breakpoints, including the stepping with signals cases. The test uses "hack/trick" to make it work on all (or most) platforms -- it doesn't really hard code a breakpoint instruction. Tested on x86_64 Fedora 20, native and gdbserver. gdb/ 2014-11-12 Pedro Alves <palves@redhat.com> * infrun.c (resume): Clear the thread's 'stepped_breakpoint' flag. Rewrite stepping over a permanent breakpoint. (thread_still_needs_step_over, proceed): Don't set stepping_over_breakpoint for permanent breakpoints. (handle_signal_stop): Don't clear stepped_breakpoint. Also pull single-step breakpoints out of the target on hardware step targets. (process_event_stop_test): If stepping a permanent breakpoint doesn't hit the step-resume breakpoint, delete the step-resume breakpoint. (switch_back_to_stepped_thread): Also check if the stepped thread has advanced already on hardware step targets. (currently_stepping): Return true if the thread stepped a breakpoint. gdb/testsuite/ 2014-11-12 Pedro Alves <palves@redhat.com> * gdb.arch/i386-bp_permanent.c: New file. * gdb.arch/i386-bp_permanent.exp: Don't skip on x86_64. (srcfile): Set to i386-bp_permanent.c. (top level): Adjust to work in both 32-bit and 64-bit modes. Test that stepi does not execute the 'leave' instruction, instead of testing it does execute. * gdb.base/bp-permanent.c: New file. * gdb.base/bp-permanent.exp: New file.
2014-11-12 11:10:49 +01:00
}
}
with_test_prefix "basics" {
# Run to the permanent breakpoint, just to make sure we've inserted it
# correctly.
# If the target fails to stop, the remainder of the test will not work
# so just return. This can happen on some simulator targets where
# the running program doesn't see breakpoints that are visible to
# the execution engine, or where writes to the .text section are
# quietly ignored.
set test "permanent breakpoint causes random signal"
gdb_test_multiple "continue" $test {
-re "exited normally.*$gdb_prompt $" {
unsupported "failed to stop at permanent breakpoint"
return
}
-re "Program received signal SIGTRAP.*$gdb_prompt $" {
pass $test
}
}
fix skipping permanent breakpoints The gdb.arch/i386-bp_permanent.exp test is currently failing an assertion recently added: (gdb) stepi ../../src/gdb/infrun.c:2237: internal-error: resume: Assertion `sig != GDB_SIGNAL_0' failed. A problem internal to GDB has been detected, further debugging may prove unreliable. Quit this debugging session? (y or n) FAIL: gdb.arch/i386-bp_permanent.exp: Single stepping past permanent breakpoint. (GDB internal error) The assertion expects that the only reason we currently need to step a breakpoint instruction is when we have a signal to deliver. But when stepping a permanent breakpoint (with or without a signal) we also reach this code. The assertion is correct and the permanent breakpoints skipping code is wrong. Consider the case of the user doing "step/stepi" when stopped at a permanent breakpoint. GDB's `resume' calls the gdbarch_skip_permanent_breakpoint hook and then happily continues stepping: /* Normally, by the time we reach `resume', the breakpoints are either removed or inserted, as appropriate. The exception is if we're sitting at a permanent breakpoint; we need to step over it, but permanent breakpoints can't be removed. So we have to test for it here. */ if (breakpoint_here_p (aspace, pc) == permanent_breakpoint_here) { gdbarch_skip_permanent_breakpoint (gdbarch, regcache); } But since gdbarch_skip_permanent_breakpoint already advanced the PC manually, this ends up executing the instruction that is _after_ the breakpoint instruction. The user-visible result is that a single-step steps two instructions. The gdb.arch/i386-bp_permanent.exp test is actually ensuring that that's indeed how things work. It runs to an int3 instruction, does "stepi", and checks that "leave" was executed with that "stepi". Like this: (gdb) b *0x0804848c Breakpoint 2 at 0x804848c (gdb) c Continuing. Breakpoint 2, 0x0804848c in standard () (gdb) disassemble Dump of assembler code for function standard: 0x08048488 <+0>: push %ebp 0x08048489 <+1>: mov %esp,%ebp 0x0804848b <+3>: push %edi => 0x0804848c <+4>: int3 0x0804848d <+5>: leave 0x0804848e <+6>: ret 0x0804848f <+7>: nop (gdb) si 0x0804848e in standard () (gdb) disassemble Dump of assembler code for function standard: 0x08048488 <+0>: push %ebp 0x08048489 <+1>: mov %esp,%ebp 0x0804848b <+3>: push %edi 0x0804848c <+4>: int3 0x0804848d <+5>: leave => 0x0804848e <+6>: ret 0x0804848f <+7>: nop End of assembler dump. (gdb) One would instead expect that a stepi at 0x0804848c stops at 0x0804848d, _before_ the "leave" is executed. This commit changes GDB this way. Care is taken to make stepping into a signal handler when the step starts at a permanent breakpoint instruction work correctly. The patch adjusts gdb.arch/i386-bp_permanent.exp in this direction, and also makes it work on x86_64 (currently it only works on i*86). The patch also adds a new gdb.base/bp-permanent.exp test that exercises many different code paths related to stepping permanent breakpoints, including the stepping with signals cases. The test uses "hack/trick" to make it work on all (or most) platforms -- it doesn't really hard code a breakpoint instruction. Tested on x86_64 Fedora 20, native and gdbserver. gdb/ 2014-11-12 Pedro Alves <palves@redhat.com> * infrun.c (resume): Clear the thread's 'stepped_breakpoint' flag. Rewrite stepping over a permanent breakpoint. (thread_still_needs_step_over, proceed): Don't set stepping_over_breakpoint for permanent breakpoints. (handle_signal_stop): Don't clear stepped_breakpoint. Also pull single-step breakpoints out of the target on hardware step targets. (process_event_stop_test): If stepping a permanent breakpoint doesn't hit the step-resume breakpoint, delete the step-resume breakpoint. (switch_back_to_stepped_thread): Also check if the stepped thread has advanced already on hardware step targets. (currently_stepping): Return true if the thread stepped a breakpoint. gdb/testsuite/ 2014-11-12 Pedro Alves <palves@redhat.com> * gdb.arch/i386-bp_permanent.c: New file. * gdb.arch/i386-bp_permanent.exp: Don't skip on x86_64. (srcfile): Set to i386-bp_permanent.c. (top level): Adjust to work in both 32-bit and 64-bit modes. Test that stepi does not execute the 'leave' instruction, instead of testing it does execute. * gdb.base/bp-permanent.c: New file. * gdb.base/bp-permanent.exp: New file.
2014-11-12 11:10:49 +01:00
# Now set a breakpoint on top, thus creating a permanent breakpoint.
gdb_breakpoint "$line_bp"
# Depending on whether this is a decr_pc_after_break arch, the PC will
# be either pointing at the permanent breakpoint address, or just
# after. Set the GDB breakpoint on top, and continue, twice. At
# least once, GDB will need to step-over the permanent breakpoint.
gdb_test "continue" "Breakpoint .*" "stop at permanent breakpoint"
gdb_test "p \$prev_counter = counter" " = $decimal"
gdb_test "continue" "Breakpoint .*" "stop at permanent breakpoint twice"
# Check that indeed the continue made progress, instead of re-trapping
# without advancing.
gdb_test "p counter - \$prev_counter" " = 1"
gdb_test "info breakpoints" \
"breakpoint.*keep.*y.*$hex.*in test at .*$srcfile:$line_bp.*already hit 2 times.*" \
"info breakpoints show enabled breakpoint"
gdb_test "disable \$bpnum"
gdb_test "commands\nset \$commands_ran = 1\nend" "" \
"set breakpoint commands"
gdb_test "info breakpoints" \
"breakpoint.*keep.*n.*$hex.*in test at .*$srcfile:$line_bp.*already hit 2 times.*" \
"info breakpoints shows disabled breakpoint"
# Run to the permanent breakpoint again. This time, since it's
# disabled, it should act as if we hadn't created it in the first
# place. IOW, we should get a random signal, and, the breakpoint's
# command should not run.
gdb_test "continue" "Program received signal SIGTRAP.*" \
"disabled permanent breakpoint doesn't explain stop"
gdb_test "info breakpoints" \
"breakpoint.*keep.*n.*$hex.*in test at .*$srcfile:$line_bp.*already hit 2 times.*" \
"info breakpoints still shows same number of hits"
gdb_test "print \$commands_ran" " = void" \
"breakpoint commands didn't run"
# Reenable the breakpoint, and check that it gets hit and accounted
# for this time.
gdb_test "enable \$bpnum" "" "reenable breakpoint"
gdb_test "continue" "Breakpoint .*" \
"stop at permanent breakpoint thrice"
gdb_test "info breakpoints" \
"breakpoint.*keep.*y.*$hex.*in test at .*$srcfile:$line_bp.*already hit 3 times.*" \
"info breakpoints shows one more hit"
gdb_test "print \$commands_ran" " = 1" "breakpoint commands ran"
# Check that stepi advances only past the permanent breakpoint, and
# not a single instruction more.
gdb_test "stepi" "after permanent bp .*" \
"single-step past permanent breakpoint"
}
with_test_prefix "next trips on permanent bp" {
delete_breakpoints
gdb_breakpoint "test_next"
gdb_continue_to_breakpoint "test_next"
gdb_breakpoint "$line_bp"
gdb_test "condition \$bpnum 0"
gdb_test "next" "after next .*"
}
if ![target_info exists gdb,nosignals] {
with_test_prefix "continue trips on nested permanent bp" {
delete_breakpoints
gdb_breakpoint "test_signal_nested"
gdb_continue_to_breakpoint "test_signal_nested"
gdb_breakpoint "$line_bp"
gdb_continue_to_breakpoint "permanent bp"
gdb_test "condition \$bpnum 0"
# Let SIGALRM trigger.
sleep 2
# We're now stopped at a permanent breakpoint, with a
# signal pending.
gdb_breakpoint "test_signal_nested_done"
gdb_continue_to_breakpoint "test_signal_nested_done"
# Ensure that the handler did run. There's one call to
# test in the mainline code, and another in the signal
# handler.
gdb_test "p counter" " = 2"
}
if [can_single_step_to_signal_handler] {
with_test_prefix "stepi signal with handler" {
delete_breakpoints
gdb_breakpoint "test_signal_with_handler"
gdb_continue_to_breakpoint "test_signal_with_handler"
gdb_breakpoint "$line_bp"
gdb_test "continue" "Breakpoint .*" "stop at permanent breakpoint"
gdb_test "queue-signal SIGUSR1"
set test "single-step to handler"
gdb_test_multiple "stepi" $test {
-re "Program received signal SIGTRAP.*$gdb_prompt $" {
fail $test
}
-re "handler .*$gdb_prompt $" {
pass $test
}
}
# Check that the mainline PC points at the permanent
# breakpoint.
gdb_test "up 2" "test .*" "up to mainline code"
gdb_test "p /x \$pc" " = $address_bp" \
"mainline pc points at permanent breakpoint"
gdb_test "continue" "Breakpoint .*" \
"stop at permanent breakpoint, out of handler"
}
with_test_prefix "stepi signal with no handler" {
gdb_breakpoint "test_signal_no_handler"
gdb_continue_to_breakpoint "test_signal_no_handler"
gdb_test "continue" "Breakpoint .*" "stop at permanent breakpoint"
gdb_test "queue-signal SIGUSR1"
gdb_test "stepi" "after permanent bp .*" \
"single-step past permanent breakpoint"
}
}
}
}
foreach always_inserted {off on} {
foreach sw_watchpoint {0 1} {
with_test_prefix "always_inserted=$always_inserted, sw_watchpoint=$sw_watchpoint" {
test $always_inserted $sw_watchpoint
}
}
}