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[PATCH] Stale breakpoint instructions, spurious SIGTRAPS.
- From: Pedro Alves <palves at redhat dot com>
- To: gdb-patches at sourceware dot org
- Cc: Nicolas Blanc <nicolas dot blanc at intel dot com>
- Date: Tue, 15 Apr 2014 19:18:06 +0100
- Subject: [PATCH] Stale breakpoint instructions, spurious SIGTRAPS.
- Authentication-results: sourceware.org; auth=none
Without the code portion of the patch, we get these failures:
FAIL: gdb.base/break-unload-file.exp: always-inserted on: break: continue
FAIL: gdb.base/break-unload-file.exp: always-inserted on: hbreak: continue
FAIL: gdb.base/sym-file.exp: stale bkpts: continue to breakpoint: end here
They all looks like random SIGTRAPs:
continue
Continuing.
Program received signal SIGTRAP, Trace/breakpoint trap.
0x0000000000400541 in foo () at ../../../src/gdb/testsuite/gdb.base/break-unload-file.c:21
21 }
(gdb) FAIL: gdb.base/break-unload-file.exp: always-inserted on: break: continue
(This is a regression caused by the remove-symbol-file command
series.)
break-unload-file.exp is about having breakpoints inserted, and then
doing "file". I caught this while writing a test that does "file
PROGRAM", while PROGRAM was already loaded, which internally does
"file" first, because I wanted to force a breakpoint_re_set, but the
test is more explicit in case GDB ever optimizes out that re-set.
The problem is that unloading the file with "file" ends up in
disable_breakpoints_in_freed_objfile, which marks all breakpoint
locations of the objfile as both shlib_disabled, _and_ clears the
inserted flag, without actually removing the breakpoints from the
inferior. Now, usually, in all-stop, breakpoints will already be
removed from the inferior before the user can issue the "file"
command, but, with non-stop, or breakpoints always-inserted on mode,
breakpoints stay inserted even while the user has the prompt. In the
latter case, then, if we let the program continue, and it executes the
address where we had previously set the breakpoint, it'll actually
execute the breakpoint instruction that we left behind...
Now, one issue is that the intent of
disable_breakpoints_in_freed_objfile is really to handle the unloading
of OBJF_USERLOADED objfiles. These are objfiles that were added with
add-symbol-file and that are removed with remove-symbol-file.
"add-symbol-file"'s docs in the manual clearly say these commands are
mention to be used to let GDB know about dynamically loaded code:
You would use this command when @var{filename} has been dynamically
loaded (by some other means) into the program that is running.
Similarly, the online help says:
(gdb) help add-symbol-file
Load symbols from FILE, assuming FILE has been dynamically loaded.
So it makes sense to, like when shared libraries are unloaded through
the generic solib machinery, mark the breakpoint locations as
shlib_disabled. But, the "file" command is not about dynamically
loaded code, it's about the main program. So the patch makes
disable_breakpoints_in_freed_objfile skip all objfiles but
OBJF_USERLOADED ones, thus skipping the main objfile.
Then, the reason that disable_breakpoints_in_freed_objfile was
clearing the inserted flag isn't clear, but likely to avoid breakpoint
removal errors, assuming remove-symbol-file was called after the
dynamic object was already unmapped from the inferior. In that case,
it'd okay to simply clear the inserted flag, but not so if the user
for example does remove-symbol-file to remove the library because he
made a mistake in the library's address, and wants to re-do
add-symbol-file with the correct address.
To address all that, I propose an alternative implementation, that
handles both cases. The patch includes changes to sym-file.exp to
cover them.
This implementation leaves the inserted flag alone, and handles
breakpoint insertion/removal failure gracefully when the locations are
in OBJF_USERLOADED objfiles, just like we handle insertion/removal
failure gracefully for locations in shared libraries.
To try to make sure we aren't patching back stale shadow memory
contents into the inferior, in case the program mapped a different
library at the same address where we had the breakpoint, without the
user having had a chance of remove-symbol-file'ing before, this adds a
new memory_validate_breakpoint function that checks if the breakpoint
instruction is still in memory. ppc_linux_memory_remove_breakpoint
does this unconditionally for all memory breakpoints, and questions
whether memory_remove_breakpoint should be changed to do this for all
breakpoints. Possibly yes, though I'm not certain, hence this
baby-steps patch.
Comments?
Tested on x86_64 Fedora 17, native and gdbserver.
gdb/
2014-04-15 Pedro Alves <palves@redhat.com>
* breakpoint.c (insert_bp_location): Tolerate errors if the
breakpoint is set in a user-loaded objfile.
(remove_breakpoint_1): Likewise. If the breakpoint is set in a
user-loaded objfile is a memory breakpoint, validate it before
uninsertion.
(disable_breakpoints_in_freed_objfile): Skip non-OBJF_USERLOADED
objfiles. Don't clear the location's inserted flag.
* mem-break.c (memory_validate_breakpoint): New function.
* objfiles.c (userloaded_objfile_contains_address_p): New
function.
* objfiles.h (userloaded_objfile_contains_address_p): Declare.
* target.h (memory_validate_breakpoint): New declaration.
gdb/testsuite/
2014-04-15 Pedro Alves <palves@redhat.com>
* gdb.base/break-unload-file.c: New file.
* gdb.base/break-unload-file.exp: New file.
* gdb.base/sym-file-lib.c (baz): New function.
* gdb.base/sym-file-loader.c (struct segment) <mapped_size>: New
field.
(load): Store the segment's mapped size.
(unload): New function.
(unload_shlib): New function.
* gdb.base/sym-file-loader.h (unload_shlib): New declaration.
* gdb.base/sym-file-main.c (main): Unload, and reload the library,
set a breakpoint at baz, and call it.
* gdb.base/sym-file.exp: New tests for stale breakpoint
instructions.
---
gdb/breakpoint.c | 47 +++++++++--
gdb/mem-break.c | 33 ++++++++
gdb/objfiles.c | 16 ++++
gdb/objfiles.h | 7 ++
gdb/target.h | 6 ++
gdb/testsuite/gdb.base/break-unload-file.c | 35 +++++++++
gdb/testsuite/gdb.base/break-unload-file.exp | 112 +++++++++++++++++++++++++++
gdb/testsuite/gdb.base/sym-file-lib.c | 6 ++
gdb/testsuite/gdb.base/sym-file-loader.c | 28 +++++++
gdb/testsuite/gdb.base/sym-file-loader.h | 4 +
gdb/testsuite/gdb.base/sym-file-main.c | 26 ++++++-
gdb/testsuite/gdb.base/sym-file.exp | 49 +++++++++++-
12 files changed, 358 insertions(+), 11 deletions(-)
create mode 100644 gdb/testsuite/gdb.base/break-unload-file.c
create mode 100644 gdb/testsuite/gdb.base/break-unload-file.exp
diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index f777a4a..8c14bb1 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -2648,7 +2648,9 @@ insert_bp_location (struct bp_location *bl,
target doesn't define error codes), so we must treat
generic errors as memory errors. */
if ((bp_err == GENERIC_ERROR || bp_err == MEMORY_ERROR)
- && solib_name_from_address (bl->pspace, bl->address))
+ && (solib_name_from_address (bl->pspace, bl->address)
+ || userloaded_objfile_contains_address_p (bl->pspace,
+ bl->address)))
{
/* See also: disable_breakpoints_in_shlibs. */
bl->shlib_disabled = 1;
@@ -3778,7 +3780,27 @@ remove_breakpoint_1 (struct bp_location *bl, insertion_state_t is)
|| !(section_is_overlay (bl->section)))
{
/* No overlay handling: just remove the breakpoint. */
- val = bl->owner->ops->remove_location (bl);
+
+ /* If we're trying to uninsert a memory breakpoint that we
+ know is set in a dynamic object that is marked
+ shlib_disabled, then either the dynamic object was
+ removed with remove-symbol-file or with
+ "nosharedlibrary". In the former case, we don't know
+ whether another dynamic object might have loaded over the
+ breakpoint's address -- the user might well let us know
+ about it next with add-symbol-file (the whole point of
+ OBJF_USERLOADED is letting the user manually maintain a
+ list of dynamically loaded objects). Check if the
+ breakpoint is still inserted in memory, to avoid
+ overwriting wrong code with stale saved shadow contents.
+ HW breakpoints are independent of poking at memory and
+ must always be removed. */
+ if (bl->shlib_disabled
+ && bl->target_info.shadow_len != 0
+ && !memory_validate_breakpoint (bl->gdbarch, &bl->target_info))
+ val = 0;
+ else
+ val = bl->owner->ops->remove_location (bl);
}
else
{
@@ -3823,10 +3845,15 @@ remove_breakpoint_1 (struct bp_location *bl, insertion_state_t is)
}
}
- /* In some cases, we might not be able to remove a breakpoint
- in a shared library that has already been removed, but we
- have not yet processed the shlib unload event. */
- if (val && solib_name_from_address (bl->pspace, bl->address))
+ /* In some cases, we might not be able to remove a breakpoint in
+ a shared library that has already been removed, but we have
+ not yet processed the shlib unload event. Similarly for an
+ unloaded add-symbol-file object - the user might not yet have
+ had the chance to remove-symbol-file it. */
+ if (val && (bl->shlib_disabled
+ || solib_name_from_address (bl->pspace, bl->address)
+ || userloaded_objfile_contains_address_p (bl->pspace,
+ bl->address)))
val = 0;
if (val)
@@ -7666,7 +7693,7 @@ disable_breakpoints_in_freed_objfile (struct objfile *objfile)
/* If the file is a shared library not loaded by the user then
solib_unloaded was notified and disable_breakpoints_in_unloaded_shlib
was called. In that case there is no need to take action again. */
- if ((objfile->flags & OBJF_SHARED) && !(objfile->flags & OBJF_USERLOADED))
+ if ((objfile->flags & OBJF_USERLOADED) == 0)
return;
ALL_BREAKPOINTS (b)
@@ -7698,7 +7725,11 @@ disable_breakpoints_in_freed_objfile (struct objfile *objfile)
if (is_addr_in_objfile (loc_addr, objfile))
{
loc->shlib_disabled = 1;
- loc->inserted = 0;
+ /* At this point, we don't know whether the object was
+ unmapped from the inferior or not, so leave the
+ inserted flag alone. We'll handle failure to
+ uninsert quietly, in case the object was indeed
+ unmapped. */
mark_breakpoint_location_modified (loc);
diff --git a/gdb/mem-break.c b/gdb/mem-break.c
index 1a057df..5371bd0 100644
--- a/gdb/mem-break.c
+++ b/gdb/mem-break.c
@@ -89,3 +89,36 @@ memory_remove_breakpoint (struct target_ops *ops, struct gdbarch *gdbarch,
{
return gdbarch_memory_remove_breakpoint (gdbarch, bp_tgt);
}
+
+int
+memory_validate_breakpoint (struct gdbarch *gdbarch,
+ struct bp_target_info *bp_tgt)
+{
+ CORE_ADDR addr = bp_tgt->placed_address;
+ const gdb_byte *bp;
+ int val;
+ int bplen;
+ gdb_byte old_contents[BREAKPOINT_MAX];
+ struct cleanup *cleanup;
+ int ret;
+
+ /* Determine appropriate breakpoint contents and size for this
+ address. */
+ bp = gdbarch_breakpoint_from_pc (gdbarch, &addr, &bplen);
+
+ if (bp == NULL
+ || bp_tgt->placed_size != bplen)
+ return 0;
+
+ /* Make sure we see the memory breakpoints. */
+ cleanup = make_show_memory_breakpoints_cleanup (1);
+ val = target_read_memory (addr, old_contents, bplen);
+
+ /* If our breakpoint is no longer at the address, this means that
+ the program modified the code on us, so it is wrong to put back
+ the old value. */
+ ret = (val == 0 && memcmp (bp, old_contents, bplen) == 0);
+
+ do_cleanups (cleanup);
+ return ret;
+}
diff --git a/gdb/objfiles.c b/gdb/objfiles.c
index e212c70..81bbf24 100644
--- a/gdb/objfiles.c
+++ b/gdb/objfiles.c
@@ -1453,6 +1453,22 @@ is_addr_in_objfile (CORE_ADDR addr, const struct objfile *objfile)
return 0;
}
+int
+userloaded_objfile_contains_address_p (struct program_space *pspace,
+ CORE_ADDR address)
+{
+ struct objfile *objfile;
+
+ ALL_PSPACE_OBJFILES (pspace, objfile)
+ {
+ if ((objfile->flags & OBJF_USERLOADED) != 0
+ && is_addr_in_objfile (address, objfile))
+ return 1;
+ }
+
+ return 0;
+}
+
/* The default implementation for the "iterate_over_objfiles_in_search_order"
gdbarch method. It is equivalent to use the ALL_OBJFILES macro,
searching the objfiles in the order they are stored internally,
diff --git a/gdb/objfiles.h b/gdb/objfiles.h
index dc06c7b..6684278 100644
--- a/gdb/objfiles.h
+++ b/gdb/objfiles.h
@@ -515,6 +515,13 @@ extern void objfiles_changed (void);
extern int is_addr_in_objfile (CORE_ADDR addr, const struct objfile *objfile);
+/* Return true if ADDRESS maps into one of the sections of the
+ userloaded ("add-symbol-file") objfiles of PSPACE and false
+ otherwise. */
+
+extern int userloaded_objfile_contains_address_p (struct program_space *pspace,
+ CORE_ADDR address);
+
/* This operation deletes all objfile entries that represent solibs that
weren't explicitly loaded by the user, via e.g., the add-symbol-file
command. */
diff --git a/gdb/target.h b/gdb/target.h
index d7c6c3d..492ecb5 100644
--- a/gdb/target.h
+++ b/gdb/target.h
@@ -2110,6 +2110,12 @@ extern int memory_remove_breakpoint (struct target_ops *, struct gdbarch *,
extern int memory_insert_breakpoint (struct target_ops *, struct gdbarch *,
struct bp_target_info *);
+/* Check whether the memory at the breakpoint's placed address still
+ contains the expected breakpoint instruction. */
+
+extern int memory_validate_breakpoint (struct gdbarch *gdbarch,
+ struct bp_target_info *bp_tgt);
+
extern int default_memory_remove_breakpoint (struct gdbarch *,
struct bp_target_info *);
diff --git a/gdb/testsuite/gdb.base/break-unload-file.c b/gdb/testsuite/gdb.base/break-unload-file.c
new file mode 100644
index 0000000..b0524f2
--- /dev/null
+++ b/gdb/testsuite/gdb.base/break-unload-file.c
@@ -0,0 +1,35 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2014 Free Software Foundation, Inc.
+
+ 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/>. */
+
+void
+foo (void)
+{
+}
+
+void
+bar (void)
+{
+}
+
+int
+main (void)
+{
+ foo ();
+ bar ();
+
+ return 0;
+}
diff --git a/gdb/testsuite/gdb.base/break-unload-file.exp b/gdb/testsuite/gdb.base/break-unload-file.exp
new file mode 100644
index 0000000..c3ef6a8
--- /dev/null
+++ b/gdb/testsuite/gdb.base/break-unload-file.exp
@@ -0,0 +1,112 @@
+# Copyright 2014 Free Software Foundation, Inc.
+
+# 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/>. */
+
+# Test that "file" doesn't leave stale breakpoints planted in the
+# target.
+
+standard_testfile
+
+if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} {
+ return -1
+}
+
+if ![runto_main] then {
+ fail "Can't run to main"
+ return 0
+}
+
+# Run the test proper. ALWAYS_INSERT determines whether
+# always-inserted mode is on/off, and BREAK_COMMAND is the break
+# command being tested.
+#
+proc test_break { always_inserted break_command } {
+ global gdb_prompt binfile
+
+ with_test_prefix "always-inserted $always_inserted: $break_command" {
+ clean_restart $binfile
+
+ if ![runto_main] then {
+ fail "Can't run to main"
+ return
+ }
+
+ delete_breakpoints
+
+ gdb_test_no_output "set breakpoint always-inserted $always_inserted"
+
+ gdb_test "$break_command foo" ".*reakpoint .* at .*"
+
+ # Remove the file, while the breakpoint above is inserted in a
+ # function in the main objfile. GDB used to have a bug where
+ # it would mark the breakpoint as uninserted, but actually
+ # would leave it inserted in the target.
+ set test "file"
+ gdb_test_multiple "file" $test {
+ -re "Are you sure you want to change the file. .*y or n. $" {
+ send_gdb "y\n"
+ exp_continue
+ }
+ -re "Discard symbol table from `.*'? .y or n. $" {
+ send_gdb "y\n"
+ exp_continue
+ }
+ -re "No symbol file now\\.\r\n$gdb_prompt $" {
+ pass $test
+ }
+ }
+
+ gdb_test "info break" "y.*PENDING.*foo"
+
+ # Now delete the breakpoint from GDB's tables, to make sure
+ # GDB doesn't reinsert it, masking the bug (with the bug, on
+ # re-insert, GDB would fill the shadow buffer with a
+ # breakpoint instruction).
+ set test "delete"
+ gdb_test_multiple $test $test {
+ -re ".*y or n. $" {
+ send_gdb "y\n"
+ exp_continue
+ }
+ -re "$gdb_prompt $" {
+ pass $test
+ }
+ }
+
+ # Re-add symbols back.
+ set test "file \$binfile"
+ gdb_test_multiple "file $binfile" $test {
+ -re "Are you sure you want to change the file. .*y or n. $" {
+ send_gdb "y\n"
+ exp_continue
+ }
+ -re "Reading symbols from.*done.*$gdb_prompt $" {
+ pass $test
+ }
+ }
+
+ # Run to another function now. With the bug, GDB would trip
+ # on a spurious trap at foo.
+ gdb_test "b bar" ".*reakpoint .* at .*"
+ gdb_test "continue" "Breakpoint .*, bar .*"
+ }
+}
+
+# While it doesn't trigger the original bug this is a regression test
+# for, test with breakpoint always-inserted off for extra coverage.
+foreach always_inserted { "off" "on" } {
+ foreach break_command { "break" "hbreak" } {
+ test_break $always_inserted $break_command
+ }
+}
diff --git a/gdb/testsuite/gdb.base/sym-file-lib.c b/gdb/testsuite/gdb.base/sym-file-lib.c
index d0c8847..67ac9ad 100644
--- a/gdb/testsuite/gdb.base/sym-file-lib.c
+++ b/gdb/testsuite/gdb.base/sym-file-lib.c
@@ -24,3 +24,9 @@ foo (int a)
{
return a; /* gdb break at foo */
}
+
+extern int
+baz (int a)
+{
+ return a; /* gdb break at baz */
+}
diff --git a/gdb/testsuite/gdb.base/sym-file-loader.c b/gdb/testsuite/gdb.base/sym-file-loader.c
index d10065e..0b0039d 100644
--- a/gdb/testsuite/gdb.base/sym-file-loader.c
+++ b/gdb/testsuite/gdb.base/sym-file-loader.c
@@ -60,6 +60,7 @@ sizeof ((hdr)->field) == sizeof (Elf_Addr) ? *(Elf_Addr *) (hdr)->field : \
struct segment
{
uint8_t *mapped_addr;
+ size_t mapped_size;
Elf_External_Phdr *phdr;
struct segment *next;
};
@@ -101,6 +102,7 @@ load (uint8_t *addr, Elf_External_Phdr *phdr, struct segment *tail_seg)
{
struct segment *seg = NULL;
uint8_t *mapped_addr = NULL;
+ size_t mapped_size = 0;
void *from = NULL;
void *to = NULL;
@@ -110,6 +112,7 @@ load (uint8_t *addr, Elf_External_Phdr *phdr, struct segment *tail_seg)
mapped_addr = (uint8_t *) mmap ((void *) GETADDR (phdr, p_vaddr),
GET (phdr, p_memsz), perm,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+ mapped_size = GET (phdr, p_memsz);
from = (void *) (addr + GET (phdr, p_offset));
to = (void *) mapped_addr;
@@ -122,6 +125,7 @@ load (uint8_t *addr, Elf_External_Phdr *phdr, struct segment *tail_seg)
return 0;
seg->mapped_addr = mapped_addr;
+ seg->mapped_size = mapped_size;
seg->phdr = phdr;
seg->next = 0;
@@ -173,6 +177,30 @@ get_origin (void)
return self_path;
}
+/* Unload/unmap a segment. */
+
+static void
+unload (struct segment *seg)
+{
+ munmap (seg->mapped_addr, seg->mapped_size);
+ free (seg);
+}
+
+void
+unload_shlib (struct library *lib)
+{
+ struct segment *seg, *next_seg;
+
+ for (seg = lib->segments; seg != NULL; seg = next_seg)
+ {
+ next_seg = seg->next;
+ unload (seg);
+ }
+
+ close (lib->fd);
+ free (lib);
+}
+
/* Mini shared library loader. No reallocation
is performed for the sake of simplicity. */
diff --git a/gdb/testsuite/gdb.base/sym-file-loader.h b/gdb/testsuite/gdb.base/sym-file-loader.h
index c6b1af3..7798a40 100644
--- a/gdb/testsuite/gdb.base/sym-file-loader.h
+++ b/gdb/testsuite/gdb.base/sym-file-loader.h
@@ -25,6 +25,10 @@ struct library;
struct library *load_shlib (const char *file);
+/* Unload a library. */
+
+void unload_shlib (struct library *lib);
+
/* Lookup the address of FUNC. */
int lookup_function (struct library *lib, const char *func, void **addr);
diff --git a/gdb/testsuite/gdb.base/sym-file-main.c b/gdb/testsuite/gdb.base/sym-file-main.c
index b48a1c2..b6e36df 100644
--- a/gdb/testsuite/gdb.base/sym-file-main.c
+++ b/gdb/testsuite/gdb.base/sym-file-main.c
@@ -42,6 +42,8 @@ main (int argc, const char *argv[])
char *text_addr = NULL;
int (*pbar) () = NULL;
int (*pfoo) (int) = NULL;
+ int (*pbaz) () = NULL;
+ int i;
lib = load_shlib (file);
if (lib == NULL)
@@ -64,8 +66,28 @@ main (int argc, const char *argv[])
(*pfoo) (2);
- /* Notify GDB to remove the symbol file. */
+ /* Unload the library, invalidating all memory breakpoints. */
+ unload_shlib (lib);
+
+ /* Notify GDB to remove the symbol file. Also check that GDB
+ doesn't complain that it can't remove breakpoints from the
+ unmapped library. */
gdb_remove_symbol_file (text_addr);
- return 0;
+ /* Reload the library. */
+ lib = load_shlib (file); /* reload lib here */
+ if (lib == NULL)
+ return 1;
+
+ if (get_text_addr (lib, (void **) &text_addr) != 0)
+ return 1;
+
+ gdb_add_symbol_file (text_addr, file);
+
+ if (lookup_function (lib, "baz", (void *) &pbaz) != 0)
+ return 1;
+
+ (*pbaz) ();
+
+ return 0; /* end here */
}
diff --git a/gdb/testsuite/gdb.base/sym-file.exp b/gdb/testsuite/gdb.base/sym-file.exp
index c87c3c7..48fb193 100644
--- a/gdb/testsuite/gdb.base/sym-file.exp
+++ b/gdb/testsuite/gdb.base/sym-file.exp
@@ -27,6 +27,7 @@
# 11) 'info files' must not display ${lib_basename}, anymore.
# 12) Check that the breakpoints at foo and bar are pending.
# 13) Check that the execution can continue without error.
+# 14) Regression test for a stale breakpoints bug.
if {![is_elf_target]} {
return 0
@@ -159,4 +160,50 @@ gdb_test "info breakpoints 4" \
"breakpoint at bar is pending"
# 13) Check that the execution can continue without error.
-gdb_continue_to_end
+set lnum_reload [gdb_get_line_number "reload lib here"]
+gdb_breakpoint $lnum_reload
+gdb_continue_to_breakpoint reload ".*${srcfile}:$lnum_reload.*"
+
+# 14) Regression test for a stale breakpoints bug. Check whether
+# unloading symbols manually without the program actually unloading
+# the library, when breakpoints are inserted doesn't leave stale
+# breakpoints behind.
+with_test_prefix "stale bkpts" {
+ # Force breakpoints always inserted.
+ gdb_test_no_output "set breakpoint always-inserted on"
+
+ # Get past the library reload.
+ gdb_continue_to_breakpoint gdb_add_symbol_file
+
+ # Load the library's symbols.
+ gdb_test "add-symbol-file ${lib_syms} addr" \
+ "Reading symbols from .*${lib_syms}\\.\\.\\.done\\." \
+ "add-symbol-file ${lib_basename}.so addr" \
+ "add symbol table from file \".*${lib_syms}\"\
+at.*\\(y or n\\) " \
+ "y"
+
+ # Set a breakpoint at baz, in the library.
+ gdb_breakpoint baz
+
+ gdb_test "info breakpoints 7" ".*y.*0x.*in baz.*" \
+ "breakpoint at baz is resolved"
+
+ # Unload symbols manually without the program actually unloading
+ # the library.
+ gdb_test "remove-symbol-file -a addr" \
+ "" \
+ "remove-symbol-file -a addr" \
+ "Remove symbol table from file \".*${lib_basename}\\.so\"\\?\
+.*\\(y or n\\) " \
+ "y"
+
+ gdb_test "info breakpoints 7" ".*PENDING.*" \
+ "breakpoint at baz is pending"
+
+ # Check that execution can continue without error. If GDB leaves
+ # breakpoints behind, we'll get back a spurious SIGTRAP.
+ set lnum_end [gdb_get_line_number "end here"]
+ gdb_breakpoint $lnum_end
+ gdb_continue_to_breakpoint "end here" ".*end here.*"
+}
--
1.7.11.7