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binutils-gdb/gdb/testsuite/gdb.ada/mi_var_array.exp

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GDB copyright headers update after running GDB's copyright.py script. gdb/ChangeLog: Update year range in copyright notice of all files.
2016-01-01 12:33:14 +08:00
# Copyright 2015-2016 Free Software Foundation, Inc.
[Ada/varobj] number of children of null pointer to dynamic array. This is preparation work to avoid a regression in the Ada/varobj. An upcoming patch is going to add support for types in DWARF which have dynamic properties whose value is a reference to another DIE. Consider for instance the following declaration: type Variant_Type (N : Int := 0) is record F : String(1 .. N) := (others => 'x'); end record; type Variant_Type_Access is access all Variant_Type; VTA : Variant_Type_Access := null; This declares a variable "VTA" which is an access (=pointer) to a variant record Variant_Type. This record contains two components, the first being "N" (the discriminant), and the second being "F", an array whose lower bound is 1, and whose upper bound depends on the value of "N" (the discriminant). Of interest to us, here, is that second component ("F"), and in particular its bounds. The debugging info, and in particular the info for the array looks like the following... .uleb128 0x9 # (DIE (0x91) DW_TAG_array_type) .long .LASF16 # DW_AT_name: "bar__variant_type__T2b" .long 0xac # DW_AT_GNAT_descriptive_type .long 0x2cb # DW_AT_type .long 0xac # DW_AT_sibling .uleb128 0xa # (DIE (0xa2) DW_TAG_subrange_type) .long 0xc4 # DW_AT_type .long 0x87 # DW_AT_upper_bound .byte 0 # end of children of DIE 0x91 ... where the upper bound of the array's subrange type is a reference to "n"'s DIE (0x87): .uleb128 0x8 # (DIE (0x87) DW_TAG_member) .ascii "n\0" # DW_AT_name [...] Once the patch to handle this dynamic property gets applied, this is what happens when creating a varobj for variable "VTA" (whose value is null), and then trying to list its children: (gdb) -var-create vta * vta ^done,name="vta",numchild="2",value="0x0", type="bar.variant_type_access",has_more="0" (gdb) -var-list-children 1 vta ^done,numchild="2", children=[child={name="vta.n",[...]}, child={name="vta.f",exp="f", numchild="43877616", <<<<----- value="[43877616]", <<<<----- type="array (1 .. n) of character"}], has_more="0" It has an odd number of children. In this case, we cannot really determine the number of children, since that number depends on the value of a field in a record for which we do not have a value. Up to now, the value we've been displaying is zero - meaning we have an empty array. What happens in this case, is that, because the VTA is a null pointer, we're not able to resolve the pointer's target type, and therefore end up asking ada_varobj_get_array_number_of_children to return the number of elements in that array; for that, it relies blindly on get_array_bounds, which assumes the type is no longer dynamic, and therefore the reads the bound without seeing that it's value is actually a reference rather than a resolved constant. This patch prevents the issue by explicitly handling the case of dynamic arrays, and returning zero child in that case. gdb/ChangeLog: * ada-varobj.c (ada_varobj_get_array_number_of_children): Return zero if PARENT_VALUE is NULL and parent_type's range type is dynamic. gdb/testsuite/ChangeLog: * gdb.ada/mi_var_array: New testcase. Tested on x86_64-linux.
2015-01-14 22:39:24 +08:00
#
# 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/>.
load_lib "ada.exp"
standard_ada_testfile bar
if {[gdb_compile_ada "${srcfile}" "${binfile}" executable [list debug]] != "" } {
return -1
}
load_lib mi-support.exp
set MIFLAGS "-i=mi"
gdb_exit
if [mi_gdb_start] {
continue
}
mi_delete_breakpoints
mi_gdb_reinitialize_dir $srcdir/$subdir
mi_gdb_load ${binfile}
if ![mi_run_to_main] then {
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
2016-12-02 04:40:05 +08:00
fail "cannot run to main, testcase aborted"
[Ada/varobj] number of children of null pointer to dynamic array. This is preparation work to avoid a regression in the Ada/varobj. An upcoming patch is going to add support for types in DWARF which have dynamic properties whose value is a reference to another DIE. Consider for instance the following declaration: type Variant_Type (N : Int := 0) is record F : String(1 .. N) := (others => 'x'); end record; type Variant_Type_Access is access all Variant_Type; VTA : Variant_Type_Access := null; This declares a variable "VTA" which is an access (=pointer) to a variant record Variant_Type. This record contains two components, the first being "N" (the discriminant), and the second being "F", an array whose lower bound is 1, and whose upper bound depends on the value of "N" (the discriminant). Of interest to us, here, is that second component ("F"), and in particular its bounds. The debugging info, and in particular the info for the array looks like the following... .uleb128 0x9 # (DIE (0x91) DW_TAG_array_type) .long .LASF16 # DW_AT_name: "bar__variant_type__T2b" .long 0xac # DW_AT_GNAT_descriptive_type .long 0x2cb # DW_AT_type .long 0xac # DW_AT_sibling .uleb128 0xa # (DIE (0xa2) DW_TAG_subrange_type) .long 0xc4 # DW_AT_type .long 0x87 # DW_AT_upper_bound .byte 0 # end of children of DIE 0x91 ... where the upper bound of the array's subrange type is a reference to "n"'s DIE (0x87): .uleb128 0x8 # (DIE (0x87) DW_TAG_member) .ascii "n\0" # DW_AT_name [...] Once the patch to handle this dynamic property gets applied, this is what happens when creating a varobj for variable "VTA" (whose value is null), and then trying to list its children: (gdb) -var-create vta * vta ^done,name="vta",numchild="2",value="0x0", type="bar.variant_type_access",has_more="0" (gdb) -var-list-children 1 vta ^done,numchild="2", children=[child={name="vta.n",[...]}, child={name="vta.f",exp="f", numchild="43877616", <<<<----- value="[43877616]", <<<<----- type="array (1 .. n) of character"}], has_more="0" It has an odd number of children. In this case, we cannot really determine the number of children, since that number depends on the value of a field in a record for which we do not have a value. Up to now, the value we've been displaying is zero - meaning we have an empty array. What happens in this case, is that, because the VTA is a null pointer, we're not able to resolve the pointer's target type, and therefore end up asking ada_varobj_get_array_number_of_children to return the number of elements in that array; for that, it relies blindly on get_array_bounds, which assumes the type is no longer dynamic, and therefore the reads the bound without seeing that it's value is actually a reference rather than a resolved constant. This patch prevents the issue by explicitly handling the case of dynamic arrays, and returning zero child in that case. gdb/ChangeLog: * ada-varobj.c (ada_varobj_get_array_number_of_children): Return zero if PARENT_VALUE is NULL and parent_type's range type is dynamic. gdb/testsuite/ChangeLog: * gdb.ada/mi_var_array: New testcase. Tested on x86_64-linux.
2015-01-14 22:39:24 +08:00
return 0
}
set bp_location [gdb_get_line_number "STOP" ${testdir}/bar.adb]
mi_continue_to_line \
"bar.adb:$bp_location" \
"stop at start of main Ada procedure"
mi_gdb_test "-var-create vta * vta" \
"\\^done,name=\"vta\",numchild=\"2\",.*" \
Fix test names starting with uppercase using multi-line gdb_test/mi_gdb_test This fixes offender testcases that have test names starting with uppercase when using gdb_test/mi_gdb_test in a multi-line construct. gdb/testsuite/ChangeLog 2016-12-01 Luis Machado <lgustavo@codesourcery.com> Fix test names starting with uppercase throughout the files. * gdb.ada/array_return.exp * gdb.ada/expr_delims.exp * gdb.ada/mi_dyn_arr.exp * gdb.ada/mi_interface.exp * gdb.ada/mi_var_array.exp * gdb.ada/watch_arg.exp * gdb.arch/alpha-step.exp * gdb.arch/altivec-regs.exp * gdb.arch/e500-regs.exp * gdb.arch/powerpc-d128-regs.exp * gdb.base/arrayidx.exp * gdb.base/break.exp * gdb.base/checkpoint.exp * gdb.base/debug-expr.exp * gdb.base/dmsym.exp * gdb.base/radix.exp * gdb.base/sepdebug.exp * gdb.base/testenv.exp * gdb.base/watch_thread_num.exp * gdb.base/watchpoint-cond-gone.exp * gdb.cell/break.exp * gdb.cell/ea-cache.exp * gdb.compile/compile.exp * gdb.cp/gdb2495.exp * gdb.gdb/selftest.exp * gdb.gdb/xfullpath.exp * gdb.go/hello.exp * gdb.go/integers.exp * gdb.objc/basicclass.exp * gdb.pascal/hello.exp * gdb.pascal/integers.exp * gdb.python/py-breakpoint.exp * gdb.python/py-cmd.exp * gdb.python/py-linetable.exp * gdb.python/py-xmethods.exp * gdb.python/python.exp * gdb.reverse/consecutive-precsave.exp * gdb.reverse/finish-precsave.exp * gdb.reverse/i386-precsave.exp * gdb.reverse/machinestate-precsave.exp * gdb.reverse/sigall-precsave.exp * gdb.reverse/solib-precsave.exp * gdb.reverse/step-precsave.exp * gdb.reverse/until-precsave.exp * gdb.reverse/watch-precsave.exp * gdb.threads/leader-exit.exp * gdb.threads/pthreads.exp * gdb.threads/wp-replication.exp * gdb.trace/actions.exp * gdb.trace/mi-tsv-changed.exp * gdb.trace/tsv.exp
2016-12-02 04:44:38 +08:00
"create bt varobj"
[Ada/varobj] number of children of null pointer to dynamic array. This is preparation work to avoid a regression in the Ada/varobj. An upcoming patch is going to add support for types in DWARF which have dynamic properties whose value is a reference to another DIE. Consider for instance the following declaration: type Variant_Type (N : Int := 0) is record F : String(1 .. N) := (others => 'x'); end record; type Variant_Type_Access is access all Variant_Type; VTA : Variant_Type_Access := null; This declares a variable "VTA" which is an access (=pointer) to a variant record Variant_Type. This record contains two components, the first being "N" (the discriminant), and the second being "F", an array whose lower bound is 1, and whose upper bound depends on the value of "N" (the discriminant). Of interest to us, here, is that second component ("F"), and in particular its bounds. The debugging info, and in particular the info for the array looks like the following... .uleb128 0x9 # (DIE (0x91) DW_TAG_array_type) .long .LASF16 # DW_AT_name: "bar__variant_type__T2b" .long 0xac # DW_AT_GNAT_descriptive_type .long 0x2cb # DW_AT_type .long 0xac # DW_AT_sibling .uleb128 0xa # (DIE (0xa2) DW_TAG_subrange_type) .long 0xc4 # DW_AT_type .long 0x87 # DW_AT_upper_bound .byte 0 # end of children of DIE 0x91 ... where the upper bound of the array's subrange type is a reference to "n"'s DIE (0x87): .uleb128 0x8 # (DIE (0x87) DW_TAG_member) .ascii "n\0" # DW_AT_name [...] Once the patch to handle this dynamic property gets applied, this is what happens when creating a varobj for variable "VTA" (whose value is null), and then trying to list its children: (gdb) -var-create vta * vta ^done,name="vta",numchild="2",value="0x0", type="bar.variant_type_access",has_more="0" (gdb) -var-list-children 1 vta ^done,numchild="2", children=[child={name="vta.n",[...]}, child={name="vta.f",exp="f", numchild="43877616", <<<<----- value="[43877616]", <<<<----- type="array (1 .. n) of character"}], has_more="0" It has an odd number of children. In this case, we cannot really determine the number of children, since that number depends on the value of a field in a record for which we do not have a value. Up to now, the value we've been displaying is zero - meaning we have an empty array. What happens in this case, is that, because the VTA is a null pointer, we're not able to resolve the pointer's target type, and therefore end up asking ada_varobj_get_array_number_of_children to return the number of elements in that array; for that, it relies blindly on get_array_bounds, which assumes the type is no longer dynamic, and therefore the reads the bound without seeing that it's value is actually a reference rather than a resolved constant. This patch prevents the issue by explicitly handling the case of dynamic arrays, and returning zero child in that case. gdb/ChangeLog: * ada-varobj.c (ada_varobj_get_array_number_of_children): Return zero if PARENT_VALUE is NULL and parent_type's range type is dynamic. gdb/testsuite/ChangeLog: * gdb.ada/mi_var_array: New testcase. Tested on x86_64-linux.
2015-01-14 22:39:24 +08:00
mi_gdb_test "-var-list-children vta" \
"\\^done,numchild=\"2\",children=\\\[child={name=\"vta.n\",exp=\"n\",numchild=\"0\",type=\"bar\\.int\"},child={name=\"vta.f\",exp=\"f\",numchild=\"0\",type=\"array \\(1 .. n\\) of character\"}\\\],.*" \
"list vta's children"
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