Support dynamically computed convenience variables in get_internalvar_integer

When using $_thread in info threads to showonly the current thread,
you get this error:
```
(gdb) info thread $_thread
Convenience variable must have integer value.
Args must be numbers or '$' variables.
```

It's because $_thread is a dynamically computed convenience
variable, which isn't supported yet by get_internalvar_integer.

Now the output looks like this:
```
(gdb) info threads $_thread
  Id   Target Id           Frame
* 1    Thread 10640.0x2680 main () at C:/src/repos/binutils-gdb.git/gdb/testsuite/gdb.base/gdbvars.c:21
```

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=17600
Approved-By: Tom Tromey <tom@tromey.com>

diff --git a/gdb/testsuite/gdb.base/gdbvars.exp b/gdb/testsuite/gdb.base/gdbvars.exp
index cb6656c176f648354b1e428680db992ae187960c..d4b2860de7f3dda439e37edbfbcc346a40230fee 100644 (file)
--- a/gdb/testsuite/gdb.base/gdbvars.exp
+++ b/gdb/testsuite/gdb.base/gdbvars.exp
@@ -158,6 +158,11 @@ proc test_with_program {} {
        "Set a new convenience variable to a program variable"
     gdb_test "print /x \$prog_var" " = $hex" \
        "Print contents of new convenience variable of program variable"
+
+    # Test $_thread/$_inferior convenience variables in various commands.
+    gdb_test "info threads \$_thread" "\\* 1 .* main.*"
+    gdb_test "info inferiors \$_inferior" "\\* 1 .* process.*"
+    gdb_test "break foo_int thread \$_thread" "Breakpoint \[0-9\]*.*"
 }
 
 gdb_test_no_output "set print sevenbit-strings"

diff --git a/gdb/thread.c b/gdb/thread.c
index c0ed64e5f8bb4915ab8518d66c4d3e07c562c49d..85bdbaa6cd8b84bacac1c78389ceb2acf372467a 100644 (file)
--- a/gdb/thread.c
+++ b/gdb/thread.c
@@ -1129,6 +1129,10 @@ print_thread_info_1 (struct ui_out *uiout, const char *requested_threads,
 
        for (thread_info *tp : all_threads ())
          {
+           /* In case REQUESTED_THREADS contains $_thread.  */
+           if (current_thread != nullptr)
+             switch_to_thread (current_thread);
+
            if (!should_print_thread (requested_threads, default_inf_num,
                                      global_ids, pid, tp))
              continue;
@@ -1176,6 +1180,10 @@ print_thread_info_1 (struct ui_out *uiout, const char *requested_threads,
          if (tp == current_thread && tp->state == THREAD_EXITED)
            current_exited = true;
 
+         /* In case REQUESTED_THREADS contains $_thread.  */
+         if (current_thread != nullptr)
+           switch_to_thread (current_thread);
+
          if (!should_print_thread (requested_threads, default_inf_num,
                                    global_ids, pid, tp))
            continue;

diff --git a/gdb/value.c b/gdb/value.c
index 1a3985582ba569ef75ee6f3d1924b9dbae9ec974..e9308b04f933214b539178cfb9bc529f2a8839c1 100644 (file)
--- a/gdb/value.c
+++ b/gdb/value.c
@@ -2119,6 +2119,21 @@ get_internalvar_integer (struct internalvar *var, LONGEST *result)
        }
     }
 
+  if (var->kind == INTERNALVAR_MAKE_VALUE)
+    {
+      struct gdbarch *gdbarch = get_current_arch ();
+      struct value *val
+       = (*var->u.make_value.functions->make_value) (gdbarch, var,
+                                                     var->u.make_value.data);
+      struct type *type = check_typedef (val->type ());
+
+      if (type->code () == TYPE_CODE_INT)
+       {
+         *result = value_as_long (val);
+         return 1;
+       }
+    }
+
   return 0;
 }