gdb, infcmd: support jump command in multi-inferior case

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.

This is done by having the jump_command function use
decode_line_with_current_source rather than
decode_line_with_last_displayed, which makes sense,
the *_current_source function always looks up a location based on the
current thread's location -- if a user is asking the current thread to
jump, then surely their destination should be relative to where the
current thread is located.

Then, inside decode_line_with_current_source, the call to
decode_line_1 is updated to pass through the current program_space,
which will limit the returned locations to those in the current
program space.

Approved-By: Andrew Burgess <aburgess@redhat.com>

3 files changed, 98 insertions, 88 deletions

diff --git a/gdb/infcmd.c b/gdb/infcmd.c
index 15702f8..96c5fea 100644
--- a/gdb/infcmd.c
+++ b/gdb/infcmd.c
@@ -1068,7 +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);
+    = decode_line_with_current_source (arg, DECODE_LINE_FUNFIRSTLINE);
   if (sals.size () != 1)
     {
       /* If multiple sal-objects were found, try dropping those that aren't
diff --git a/gdb/linespec.c b/gdb/linespec.c
index 7d969f3..afa9eb4 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);
diff --git a/gdb/testsuite/gdb.base/jump.exp b/gdb/testsuite/gdb.base/jump.exp
index 032c4a62..63eec8a 100644
--- a/gdb/testsuite/gdb.base/jump.exp
+++ b/gdb/testsuite/gdb.base/jump.exp
@@ -18,99 +18,108 @@ 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]} {
+    return -1
+}
 
-# Start with a fresh gdb
+# General testing of the 'jump' command.  GDB is already started.
+# There might be multiple inferior in the current debug session, in
+# which case, the relevant inferior is already selected.
+proc do_tests {} {
+    # 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}
+set num_inferiors 1
+if {![use_gdb_stub]} {
+    set num_inferiors 2
+}
 
+# Run to main, add inferiors if needed.
 if {![runto_main]} {
-  return -1
+    return -1
 }
-
-# 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 $expect_out(1,string)
-	pass "break before jump to non-call"
+for {set inf 2} {$inf <= $num_inferiors} {incr inf} {
+    # 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 <= $num_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