gdb/gdb-rhbz2152431-label-symbol-value.patch

From FEDORA_PATCHES Mon Sep 17 00:00:00 2001
From: Andrew Burgess <aburgess@redhat.com>
Date: Mon, 19 Dec 2022 15:57:59 +0000
Subject: gdb-rhbz2152431-label-symbol-value.patch

Backport these two upstream commits to fix bug 2152431:

  commit 38665d717a3e65c70e6432243d5eed9728a4888a
  Date:   Mon Dec 12 14:09:40 2022 +0000

      gdb: use gdb_assert not internal_error

And:

  commit c3efaf0afd9d37004c42cdfd3ce0c1bfa979c45e
  Date:   Mon Dec 12 14:05:22 2022 +0000

      gdb: fix crash when getting the value of a label symbol

diff --git a/gdb/findvar.c b/gdb/findvar.c
--- a/gdb/findvar.c
+++ b/gdb/findvar.c
@@ -152,11 +152,7 @@ extract_long_unsigned_integer (const gdb_byte *addr, int orig_len,
 CORE_ADDR
 extract_typed_address (const gdb_byte *buf, struct type *type)
 {
-  if (!type->is_pointer_or_reference ())
-    internal_error (__FILE__, __LINE__,
-		    _("extract_typed_address: "
-		    "type is not a pointer or reference"));
-
+  gdb_assert (type->is_pointer_or_reference ());
   return gdbarch_pointer_to_address (type->arch (), type, buf);
 }
 
@@ -205,11 +201,7 @@ template void store_integer (gdb_byte *addr, int len,
 void
 store_typed_address (gdb_byte *buf, struct type *type, CORE_ADDR addr)
 {
-  if (!type->is_pointer_or_reference ())
-    internal_error (__FILE__, __LINE__,
-		    _("store_typed_address: "
-		    "type is not a pointer or reference"));
-
+  gdb_assert (type->is_pointer_or_reference ());
   gdbarch_address_to_pointer (type->arch (), type, buf, addr);
 }
 
@@ -634,19 +626,32 @@ language_defn::read_var_value (struct symbol *var,
 
     case LOC_LABEL:
       /* Put the constant back in target format.  */
-      v = allocate_value (type);
-      if (overlay_debugging)
-	{
-	  struct objfile *var_objfile = symbol_objfile (var);
-	  addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var),
-					   var->obj_section (var_objfile));
-	  store_typed_address (value_contents_raw (v).data (), type, addr);
-	}
-      else
-	store_typed_address (value_contents_raw (v).data (), type,
-			      SYMBOL_VALUE_ADDRESS (var));
-      VALUE_LVAL (v) = not_lval;
-      return v;
+      {
+	/* Put the constant back in target format.  */
+	if (overlay_debugging)
+	  {
+	    struct objfile *var_objfile = symbol_objfile (var);
+	    addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var),
+					     var->obj_section (var_objfile));
+	  }
+	else
+	  addr = SYMBOL_VALUE_ADDRESS (var);
+
+	/* First convert the CORE_ADDR to a function pointer type, this
+	   ensures the gdbarch knows what type of pointer we are
+	   manipulating when value_from_pointer is called.  */
+	type = builtin_type (symbol_arch (var))->builtin_func_ptr;
+	v = value_from_pointer (type, addr);
+
+	/* But we want to present the value as 'void *', so cast it to the
+	   required type now, this will not change the values bit
+	   representation.  */
+	struct type *void_ptr_type
+	  = builtin_type (symbol_arch (var))->builtin_data_ptr;
+	v = value_cast_pointers (void_ptr_type, v, 0);
+	VALUE_LVAL (v) = not_lval;
+	return v;
+      }
 
     case LOC_CONST_BYTES:
       if (is_dynamic_type (type))
diff --git a/gdb/testsuite/gdb.python/py-label-symbol-value.c b/gdb/testsuite/gdb.python/py-label-symbol-value.c
new file mode 100644
--- /dev/null
+++ b/gdb/testsuite/gdb.python/py-label-symbol-value.c
@@ -0,0 +1,38 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2022 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/>.  */
+
+volatile int global_var = 1;
+
+int
+get_value ()
+{
+  return global_var;
+}
+
+int
+main (void)
+{
+  int value = get_value ();
+  if (value > 0)
+    goto some_label;
+
+  return 1;
+
+ some_label:
+
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.python/py-label-symbol-value.exp b/gdb/testsuite/gdb.python/py-label-symbol-value.exp
new file mode 100644
--- /dev/null
+++ b/gdb/testsuite/gdb.python/py-label-symbol-value.exp
@@ -0,0 +1,39 @@
+# Copyright 2022 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 that GDB handles the user asking for the value of a label
+# symbol (i.e. a symbol for a goto label).
+
+load_lib gdb-python.exp
+standard_testfile
+
+if { [prepare_for_testing "failed to prepare" ${testfile} ${srcfile}] } {
+    return -1
+}
+
+# Skip all tests if Python scripting is not enabled.
+if { [skip_python_tests] } { continue }
+
+if ![runto_main] {
+   return -1
+}
+
+# Use Python to print the value of the 'some_label' symbol.
+gdb_test "python frame = gdb.selected_frame()"
+gdb_test "python frame_pc = frame.pc()"
+gdb_test "python block = gdb.current_progspace().block_for_pc(frame_pc)"
+gdb_test "python symbol,_ = gdb.lookup_symbol('some_label', block, gdb.SYMBOL_LABEL_DOMAIN)"
+gdb_test "python print(str(symbol.value()))" "$hex <main\\+$decimal>"
+gdb_test "python print(str(symbol.value().type))" "void \\*"