Handle the static link in FrameDecorator

A co-worker requested that the DAP scope for a nested function's frame
also show the variables from outer frames.  DAP doesn't directly
support this notion, so this patch arranges to put these variables
into the inner frames "Locals" scope.

I chose to do this only for DAP.  For CLI and MI, gdb currently does
not do this, so this preserves the behavior.

Note that an earlier patch (see commit 4a1311ba) removed some code
that seemed to do something similar.  However, that code did not
actually work.

2 files changed, 123 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.dap/ada-nested.exp b/gdb/testsuite/gdb.dap/ada-nested.exp
new file mode 100644
index 0000000..1a02f4f
--- /dev/null
+++ b/gdb/testsuite/gdb.dap/ada-nested.exp
@@ -0,0 +1,91 @@
+# Copyright 2023 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/>.
+
+# Check the scope of a nested function.
+
+load_lib ada.exp
+load_lib dap-support.exp
+
+require allow_ada_tests allow_dap_tests
+
+standard_ada_testfile prog
+
+if {[gdb_compile_ada "${srcfile}" "${binfile}" executable \
+	 {debug additional_flags=-gnata}] != ""} {
+    return -1
+}
+
+if {[dap_launch $binfile] == ""} {
+    return
+}
+
+set line [gdb_get_line_number "STOP"]
+set obj [dap_check_request_and_response "set breakpoint" \
+	     setBreakpoints \
+	     [format {o source [o path [%s]] \
+			  breakpoints [a [o line [i %d]]]} \
+		  [list s $srcfile] $line]]
+set fn_bpno [dap_get_breakpoint_number $obj]
+
+dap_check_request_and_response "start inferior" configurationDone
+
+dap_wait_for_event_and_check "stopped at breakpoint" stopped \
+    "body reason" breakpoint \
+    "body hitBreakpointIds" $fn_bpno
+
+set bt [lindex [dap_check_request_and_response "backtrace" stackTrace \
+		    {o threadId [i 1]}] \
+	    0]
+set frame_id [dict get [lindex [dict get $bt body stackFrames] 0] id]
+
+set scopes [dap_check_request_and_response "get scopes" scopes \
+		[format {o frameId [i %d]} $frame_id]]
+set scopes [dict get [lindex $scopes 0] body scopes]
+
+# This is what the implementation does, so we can assume it, but check
+# just in case something changes.
+lassign $scopes args locals _ignore
+gdb_assert {[dict get $args name] == "Arguments"} "argument scope"
+gdb_assert {[dict get $locals name] == "Locals"} "local scope"
+
+gdb_assert {[dict get $locals namedVariables] == 3} "two locals"
+
+set num [dict get $locals variablesReference]
+set refs [lindex [dap_check_request_and_response "fetch variables" \
+		      "variables" \
+		      [format {o variablesReference [i %d] count [i 3]} \
+			   $num]] \
+	      0]
+
+foreach var [dict get $refs body variables] {
+    set name [dict get $var name]
+
+    switch $name {
+	"i" {
+	    gdb_assert {[dict get $var value] == "1"} "check value of i"
+	}
+	"x" {
+	    gdb_assert {[dict get $var value] == "12"} "check value of x"
+	}
+	"outer_arg" {
+	    gdb_assert {[dict get $var value] == "1"} "check value of outer_arg"
+	}
+	default {
+	    fail "unknown variable $name"
+	}
+    }
+}
+
+dap_shutdown
diff --git a/gdb/testsuite/gdb.dap/ada-nested/prog.adb b/gdb/testsuite/gdb.dap/ada-nested/prog.adb
new file mode 100644
index 0000000..6b38835
--- /dev/null
+++ b/gdb/testsuite/gdb.dap/ada-nested/prog.adb
@@ -0,0 +1,32 @@
+--  Copyright 2023 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/>.
+
+procedure Foo is
+   X  : Integer := 12;
+
+   procedure Outer (Outer_Arg : Integer) is
+      procedure Bump (Stride : Integer) is
+      begin
+         X := X + Stride;          -- STOP
+      end;
+   begin
+      Bump (Outer_Arg);
+   end;
+
+begin
+   for I in 1 .. 20 loop
+      Outer (1);
+   end loop;
+end Foo;