[PATCH v3 1/1] gdb, infcmd: Support jump command in multi-inferior case.
Andrew Burgess
aburgess@redhat.com
Wed May 24 17:33:14 GMT 2023
Matti Puputti <matti.puputti@intel.com> writes:
> Fixes the issue where jump failed if multiple inferiors run the same source.
>
> See the below example
>
> $ gdb -q ./simple
> Reading symbols from ./simple...
> (gdb) break 2
> Breakpoint 1 at 0x114e: file simple.c, line 2.
> (gdb) run
> Starting program: /temp/simple
>
> Breakpoint 1, main () at simple.c:2
> 2 int a = 42;
> (gdb) add-inferior
> [New inferior 2]
> Added inferior 2 on connection 1 (native)
> (gdb) inferior 2
> [Switching to inferior 2 [<null>] (<noexec>)]
> (gdb) info inferiors
> Num Description Connection Executable
> 1 process 6250 1 (native) /temp/simple
> * 2 <null> 1 (native)
> (gdb) file ./simple
> Reading symbols from ./simple...
> (gdb) run
> Starting program: /temp/simple
>
> Thread 2.1 "simple" hit Breakpoint 1, main () at simple.c:2
> 2 int a = 42;
> (gdb) info inferiors
> Num Description Connection Executable
> 1 process 6250 1 (native) /temp/simple
> * 2 process 6705 1 (native) /temp/simple
> (gdb) jump 3
> Unreasonable jump request
> (gdb)
>
> In this example, jump fails because the debugger finds two different
> locations, one for each inferior.
> Solution is to limit the search to the current program space.
> ---
> gdb/infcmd.c | 3 +-
> gdb/linespec.c | 7 +-
> gdb/linespec.h | 5 +-
> gdb/testsuite/gdb.base/jump.exp | 177 +++++++++++++++++---------------
> 4 files changed, 103 insertions(+), 89 deletions(-)
>
> diff --git a/gdb/infcmd.c b/gdb/infcmd.c
> index 103899432f7..a79b5d3d4d6 100644
> --- a/gdb/infcmd.c
> +++ b/gdb/infcmd.c
> @@ -1077,7 +1077,8 @@ jump_command (const char *arg, int from_tty)
> error_no_arg (_("starting address"));
>
> std::vector<symtab_and_line> sals
> - = decode_line_with_last_displayed (arg, DECODE_LINE_FUNFIRSTLINE);
> + = decode_line_with_last_displayed (arg, DECODE_LINE_FUNFIRSTLINE,
> + current_program_space);
I wonder if we should stop using decode_line_with_last_displayed here,
and instead use decode_line_with_current_source? It feels like a jump
should always be relative to the current location, rather than what we
happen to have listed.
> if (sals.size () != 1)
> error (_("Unreasonable jump request"));
>
> diff --git a/gdb/linespec.c b/gdb/linespec.c
> index 7d969f37fbf..920fd3d37b7 100644
> --- a/gdb/linespec.c
> +++ b/gdb/linespec.c
> @@ -3231,7 +3231,8 @@ decode_line_with_current_source (const char *string, int flags)
> /* See linespec.h. */
>
> std::vector<symtab_and_line>
> -decode_line_with_last_displayed (const char *string, int flags)
> +decode_line_with_last_displayed (const char *string, int flags,
> + program_space *search_pspace)
> {
> if (string == 0)
> error (_("Empty line specification."));
> @@ -3240,10 +3241,10 @@ decode_line_with_last_displayed (const char *string, int flags)
> current_language);
> std::vector<symtab_and_line> sals
> = (last_displayed_sal_is_valid ()
> - ? decode_line_1 (locspec.get (), flags, NULL,
> + ? decode_line_1 (locspec.get (), flags, search_pspace,
> get_last_displayed_symtab (),
> get_last_displayed_line ())
This change is why I started looking at the details of this patch again.
I'm not sure this change makes sense, I would have expected us to use
get_last_displayed_pspace () here instead of search_pspace, but then it
becomes harder to describe what search_pspace does as it would only be
used below.
It we switch jump to use decode_line_with_current_source then I think
this problem goes away, the changes to decode_line_with_last_displayed
can be dropped.
At the end of this email you'll find a patch that applies on top of your
V3, which implements the change I'm suggesting. This passes all the
'jump' tests I could find in the testsuite, so I think it's fine, but
it would be great to hear your thoughts.
Thanks,
Andrew
> - : decode_line_1 (locspec.get (), flags, NULL, NULL, 0));
> + : decode_line_1 (locspec.get (), flags, search_pspace, NULL, 0));
>
> if (*string)
> error (_("Junk at end of line specification: %s"), string);
> diff --git a/gdb/linespec.h b/gdb/linespec.h
> index d5e7334fe2d..0eb9cb5d9f2 100644
> --- a/gdb/linespec.h
> +++ b/gdb/linespec.h
> @@ -139,10 +139,11 @@ extern std::vector<symtab_and_line> decode_line_with_current_source
> (const char *, int);
>
> /* Given a string, return the line specified by it, using the last displayed
> - codepoint's values as defaults, or nothing if they aren't valid. */
> + codepoint's values as defaults, or nothing if they aren't valid.
> + Limit the search to given program space, if specified. */
>
> extern std::vector<symtab_and_line> decode_line_with_last_displayed
> - (const char *, int);
> + (const char *, int, program_space *search_pspace = nullptr);
>
> /* Does P represent one of the keywords? If so, return
> the keyword. If not, return NULL. */
> diff --git a/gdb/testsuite/gdb.base/jump.exp b/gdb/testsuite/gdb.base/jump.exp
> index 032c4a6279d..4c0d4ed2dbb 100644
> --- a/gdb/testsuite/gdb.base/jump.exp
> +++ b/gdb/testsuite/gdb.base/jump.exp
> @@ -18,99 +18,110 @@ clear_xfail "*-*-*"
>
> standard_testfile .c
>
> -# Build the test case
> -if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug nowarnings}] != "" } {
> - untested "failed to compile"
> - return -1
> - }
> +if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} {
> + return -1
> +}
>
>
> -# Start with a fresh gdb
> +proc do_tests {} {
> + global decimal srcfile
> +
> + # Set a breakpoint on the statement that we're about to jump to.
> + # The statement doesn't contain a function call.
> + set non_call_line [gdb_get_line_number "bp-on-non-call"]
> + gdb_breakpoint "$non_call_line"
> + set bp_on_non_call \
> + [get_integer_valueof "\$bpnum" "INVALID" "bp_on_non_call"]
> +
> + # Can we jump to the statement? Do we stop there?
> + gdb_test "jump $non_call_line" \
> + "Breakpoint ${bp_on_non_call}(\.${decimal})?, .*${srcfile}:$non_call_line.*" \
> + "jump to non-call"
> +
> + # Set a breakpoint on the statement that we're about to jump to.
> + # The statement does contain a function call.
> + set call_line [gdb_get_line_number "bp-on-call"]
> + gdb_breakpoint "$call_line"
> + set bp_on_call [get_integer_valueof "\$bpnum" "INVALID" "bp_on_call"]
> +
> + # Can we jump to the statement? Do we stop there?
> + gdb_test "jump $call_line" \
> + "Breakpoint ${bp_on_call}(\.${decimal})?, .*${srcfile}:$call_line.*" \
> + "jump to call"
> +
> + # If we disable the breakpoint at the function call, and then
> + # if we jump to that statement, do we not stop there, but at
> + # the following breakpoint?
> + gdb_test_no_output "disable $bp_on_call" "disable breakpoint on call"
> +
> + gdb_test "jump $call_line" \
> + "Breakpoint ${bp_on_non_call}(\.${decimal})?, .*${srcfile}:$non_call_line.*" \
> + "jump to call with disabled breakpoint"
> +
> + # Disable the breakpoint at the non-function call, so it won't hit
> + # if do_test is called again.
> + gdb_test_no_output "disable ${bp_on_non_call}" "disable bp_on_non_call"
> +
> + # Verify that GDB responds gracefully to the "jump" command without
> + # an argument.
> + gdb_test "jump" "Argument required .starting address.*" \
> + "jump without argument disallowed"
> +
> + # Verify that GDB responds gracefully to the "jump" command with
> + # trailing junk.
> + gdb_test "jump $call_line 100" \
> + "malformed linespec error: unexpected number, \"100\"" \
> + "jump with trailing argument junk"
> +
> + # Verify that GDB responds gracefully to a request to jump out of
> + # the current function. (Note that this will very likely cause the
> + # inferior to die. Be prepared to rerun the inferior, if further
> + # testing is desired.)
> + # Try it both ways: confirming and not confirming the jump.
> + set out_line [gdb_get_line_number "out-of-func"]
> + gdb_test "jump $out_line" \
> + "Not confirmed.*" \
> + "aborted jump out of current function" \
> + "Line $out_line is not in `main'. Jump anyway.*y or n. $" \
> + "n"
> +
> + gdb_test "jump $out_line" \
> + "Continuing at.*" \
> + "jump out of current function" \
> + "Line $out_line is not in `main'. Jump anyway.*y or n. $" \
> + "y"
> +}
>
> -clean_restart ${binfile}
>
> -if {![runto_main]} {
> - return -1
> +set inferiors 1
> +if {![use_gdb_stub]} {
> + set inferiors 2
> }
>
> -# Set a breakpoint on the statement that we're about to jump to.
> -# The statement doesn't contain a function call.
> -#
> -set bp_on_non_call 0
> -set non_call_line [gdb_get_line_number "bp-on-non-call"]
> -gdb_test_multiple "break $non_call_line" "break before jump to non-call" {
> - -re "\[Bb\]reakpoint (${decimal}) at ${hex}: file .*${srcfile}, line $non_call_line.*$gdb_prompt $" {
> - set bp_on_non_call $expect_out(1,string)
> - pass "break before jump to non-call"
> +# Run to main, add inferiors if needed.
> +for {set inf 1} {$inf <= $inferiors} {incr inf} {
> + if {$inf != 1} {
> + # Start a new inferior, and run it with the same executable.
> + gdb_test "add-inferior -exec ${binfile}" \
> + "Added inferior ${inf}.*" \
> + "add inferior ${inf} with -exec "
> + gdb_test "inferior ${inf}" \
> + "Switching to inferior ${inf} .*" \
> + "switch to inferior ${inf}"
> + }
> + if {![runto_main]} {
> + return -1
> }
> }
>
> -# Can we jump to the statement? Do we stop there?
> -#
> -gdb_test "jump $non_call_line" "Breakpoint ${decimal}, .*${srcfile}:$non_call_line.*" \
> - "jump to non-call"
> -
> -# Set a breakpoint on the statement that we're about to jump to.
> -# The statement does contain a function call.
> -#
> -set bp_on_call 0
> -set call_line [gdb_get_line_number "bp-on-call"]
> -gdb_test_multiple "break $call_line" "break before jump to call" {
> - -re "\[Bb\]reakpoint (${decimal}) at ${hex}: file .*${srcfile}, line $call_line.*$gdb_prompt $" {
> - set bp_on_call $expect_out(1,string)
> - pass "break before jump to call"
> +# Run tests on all inferiors.
> +for {set inf 1} {$inf <= $inferiors} {incr inf} {
> + with_test_prefix "inferior $inf" {
> + # Switch to the target inferior.
> + gdb_test "inferior $inf" ".*Switching to inferior $inf .*"
> + # Run the tests.
> + do_tests
> }
> }
>
> -# Can we jump to the statement? Do we stop there?
> -#
> -gdb_test "jump $call_line" \
> - "Breakpoint ${decimal}, .*${srcfile}:$call_line.*" \
> - "jump to call"
> -
> -# If we disable the breakpoint at the function call, and then
> -# if we jump to that statement, do we not stop there, but at
> -# the following breakpoint?
> -#
> -gdb_test_no_output "disable $bp_on_call" "disable breakpoint on call"
> -
> -gdb_test "jump $call_line" "Breakpoint ${decimal}, .*${srcfile}:$non_call_line.*" \
> - "jump to call with disabled breakpoint"
> -
> -# Verify that GDB responds gracefully to the "jump" command without
> -# an argument.
> -#
> -gdb_test "jump" "Argument required .starting address.*" \
> - "jump without argument disallowed"
> -
> -
> -# Verify that GDB responds gracefully to the "jump" command with
> -# trailing junk.
> -#
> -gdb_test "jump $call_line 100" \
> - "malformed linespec error: unexpected number, \"100\"" \
> - "jump with trailing argument junk"
> -
> -
> -# Verify that GDB responds gracefully to a request to jump out of
> -# the current function. (Note that this will very likely cause the
> -# inferior to die. Be prepared to rerun the inferior, if further
> -# testing is desired.)
> -#
> -# Try it both ways: confirming and not confirming the jump.
> -#
> -
> -set out_line [gdb_get_line_number "out-of-func"]
> -gdb_test "jump $out_line" \
> - "Not confirmed.*" \
> - "aborted jump out of current function" \
> - "Line $out_line is not in `main'. Jump anyway.*y or n. $" \
> - "n"
> -
> -gdb_test "jump $out_line" \
> - "Continuing at.*" \
> - "jump out of current function" \
> - "Line $out_line is not in `main'. Jump anyway.*y or n. $" \
> - "y"
> -
> gdb_exit
> --
> 2.25.1
>
> Intel Deutschland GmbH
> Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
> Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
> Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva
> Chairperson of the Supervisory Board: Nicole Lau
> Registered Office: Munich
> Commercial Register: Amtsgericht Muenchen HRB 186928
---
diff --git a/gdb/infcmd.c b/gdb/infcmd.c
index 1be72ed09f0..1d10e2908ca 100644
--- a/gdb/infcmd.c
+++ b/gdb/infcmd.c
@@ -1068,8 +1068,7 @@ jump_command (const char *arg, int from_tty)
error_no_arg (_("starting address"));
std::vector<symtab_and_line> sals
- = decode_line_with_last_displayed (arg, DECODE_LINE_FUNFIRSTLINE,
- current_program_space);
+ = decode_line_with_current_source (arg, DECODE_LINE_FUNFIRSTLINE);
if (sals.size () != 1)
error (_("Unreasonable jump request"));
diff --git a/gdb/linespec.c b/gdb/linespec.c
index 920fd3d37b7..9f03a4b3604 100644
--- a/gdb/linespec.c
+++ b/gdb/linespec.c
@@ -3220,7 +3220,8 @@ decode_line_with_current_source (const char *string, int flags)
location_spec_up locspec = string_to_location_spec (&string,
current_language);
std::vector<symtab_and_line> sals
- = decode_line_1 (locspec.get (), flags, NULL, cursal.symtab, cursal.line);
+ = decode_line_1 (locspec.get (), flags, cursal.pspace, cursal.symtab,
+ cursal.line);
if (*string)
error (_("Junk at end of line specification: %s"), string);
@@ -3231,8 +3232,7 @@ decode_line_with_current_source (const char *string, int flags)
/* See linespec.h. */
std::vector<symtab_and_line>
-decode_line_with_last_displayed (const char *string, int flags,
- program_space *search_pspace)
+decode_line_with_last_displayed (const char *string, int flags)
{
if (string == 0)
error (_("Empty line specification."));
@@ -3241,10 +3241,10 @@ decode_line_with_last_displayed (const char *string, int flags,
current_language);
std::vector<symtab_and_line> sals
= (last_displayed_sal_is_valid ()
- ? decode_line_1 (locspec.get (), flags, search_pspace,
+ ? decode_line_1 (locspec.get (), flags, NULL,
get_last_displayed_symtab (),
get_last_displayed_line ())
- : decode_line_1 (locspec.get (), flags, search_pspace, NULL, 0));
+ : decode_line_1 (locspec.get (), flags, NULL, NULL, 0));
if (*string)
error (_("Junk at end of line specification: %s"), string);
diff --git a/gdb/linespec.h b/gdb/linespec.h
index 0eb9cb5d9f2..c0eef7894d9 100644
--- a/gdb/linespec.h
+++ b/gdb/linespec.h
@@ -143,7 +143,7 @@ extern std::vector<symtab_and_line> decode_line_with_current_source
Limit the search to given program space, if specified. */
extern std::vector<symtab_and_line> decode_line_with_last_displayed
- (const char *, int, program_space *search_pspace = nullptr);
+ (const char *, int);
/* Does P represent one of the keywords? If so, return
the keyword. If not, return NULL. */
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