Re: [PATCH v3] gdb: Change "list ." command's error when no debuginfo is available

[Guinevere Larsen <blarsen@redhat.com>]

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On 5/2/24 04:54, Andrew Burgess wrote:
>> @@ -1274,25 +1276,42 @@ list_command (const char *arg, int from_tty)
>>         /* "list ." lists the default location again.  */
>>         else if (arg[0] == '.')
>>   	{
>> +	  std::optional<const symtab_and_line> cursal;
> I don't see why this needs to be a std::optional.  Along both branches
> of the following if/else we assign cursal a value.

You're right. I think this is a leftover from a previous strategy (or 
just a copy from Simon's email, I honestly can't remember). I've removed 
this locally

In double checking this change, I noticed that I forgot to change the 
test strings to the form suggested by Eli.  Also fixed locally. For 
convenience, this is the change:

diff --git a/gdb/cli/cli-cmds.c b/gdb/cli/cli-cmds.c
index ee3318d7910..d5c8ad33457 100644
--- a/gdb/cli/cli-cmds.c
+++ b/gdb/cli/cli-cmds.c
@@ -1276,16 +1276,16 @@ list_command (const char *arg, int from_tty)
        /* "list ." lists the default location again.  */
        else if (arg[0] == '.')
         {
-         std::optional<const symtab_and_line> cursal;
+         symtab_and_line cursal;
           if (target_has_stack ())
             {
               /* Find the current line by getting the PC of the currently
                  selected frame, and finding the line associated to it.  */
               frame_info_ptr frame = get_selected_frame (nullptr);
               CORE_ADDR curr_pc = get_frame_pc (frame);
-             cursal.emplace (find_pc_line (curr_pc, 0));
+             cursal = find_pc_line (curr_pc, 0);

-             if (cursal->symtab == nullptr)
+             if (cursal.symtab == nullptr)
                 error
                   (_("Insufficient debug info for showing source lines at "
                      "current PC (%s)."), paddress (get_frame_arch (frame),
@@ -1305,12 +1305,12 @@ list_command (const char *arg, int from_tty)
                   error (_("Insufficient debug info for showing source "
                            "lines at default location"));
                 }
-             cursal.emplace (get_current_source_symtab_and_line ());
+             cursal = get_current_source_symtab_and_line ();

-             gdb_assert (cursal->symtab != nullptr);
+             gdb_assert (cursal.symtab != nullptr);
             }

-         list_around_line (arg, *cursal);
+         list_around_line (arg, cursal);

           /* Set the repeat args so just pressing "enter" after using 
"list ."
              will print the following lines instead of the same lines 
again. */
diff --git a/gdb/testsuite/gdb.base/list-dot-nodebug.exp 
b/gdb/testsuite/gdb.base/list-dot-nodebug.exp
index 7c4144da8ab..20050a90245 100644
--- a/gdb/testsuite/gdb.base/list-dot-nodebug.exp
+++ b/gdb/testsuite/gdb.base/list-dot-nodebug.exp
@@ -54,7 +54,7 @@ foreach_with_prefix debug {"none" "some"} {
      }

      gdb_test "list ." \
-       "No debug information available to print source lines.*" \
+       "Insufficient debug info for showing source lines.*" \
         "print before start"

      if { ![runto bar] } {
@@ -62,6 +62,6 @@ foreach_with_prefix debug {"none" "some"} {
      }

      gdb_test "list ." \
-       "No debug information available to print source lines at current 
PC.*" \
+       "Insufficient debug info for showing source lines at current PC.*" \
         "print after start"
  }
diff --git a/gdb/testsuite/gdb.base/list-nodebug.exp 
b/gdb/testsuite/gdb.base/list-nodebug.exp
index 942a282083a..e07fa9e2417 100644
--- a/gdb/testsuite/gdb.base/list-nodebug.exp
+++ b/gdb/testsuite/gdb.base/list-nodebug.exp
@@ -33,8 +33,8 @@ if {![runto_main]} {

  # Check that GDB doesn't crash when we use list . on an inferior with
  # no debug information
-gdb_test "list ." "No debug.*" "first 'list .'"
+gdb_test "list ." "Insufficient debug.*" "first 'list .'"
  # This should be called twice because the first list invocation since
  # printing a frame may take a different codepath, which wouldn't
  # trigger the crash.
-gdb_test "list ." "No debug.*" "second 'list .'"
+gdb_test "list ." "Insufficient debug.*" "second 'list .'"

-- 
Cheers,
Guinevere Larsen
She/Her/Hers

>
> Thanks,
> Andrew