base/SOURCES/gdb-implicit-this.patch

Index: gdb-7.6.1/gdb/c-exp.y
===================================================================
--- gdb-7.6.1.orig/gdb/c-exp.y	2013-11-09 17:29:19.336729300 +0100
+++ gdb-7.6.1/gdb/c-exp.y	2013-11-09 17:29:21.935727454 +0100
@@ -2890,6 +2890,30 @@ classify_inner_name (const struct block
     {
     case LOC_BLOCK:
     case LOC_LABEL:
+      {
+	struct field_of_this_result fot;
+
+	/* We might have erroneously found a constructor where we wanted
+	   a type name.  The trick is ascertaining what the user wanted.
+	   If cp_lookup_nested_symbol found a constructor, but it is for a
+	   different type than CONTEXT, then this is really a type, not a
+	   constructor.  Look for the type and return that.  */
+	memset (&fot, 0, sizeof (fot));
+	check_field (type, copy, &fot);
+	if (fot.fn_field != NULL
+	    && TYPE_FN_FIELD_CONSTRUCTOR (fot.fn_field->fn_fields, 0)
+	    && !types_equal (type, fot.type))
+	  {
+	    struct symbol *sym;
+
+	    sym = lookup_symbol (copy, block, STRUCT_DOMAIN, NULL);
+	    if (sym != NULL)
+	      {
+		yylval.tsym.type = SYMBOL_TYPE (sym);
+		return TYPENAME;
+	      }
+	  }
+      }
       return ERROR;
 
     case LOC_TYPEDEF:
Index: gdb-7.6.1/gdb/symtab.c
===================================================================
--- gdb-7.6.1.orig/gdb/symtab.c	2013-11-09 17:29:19.338729298 +0100
+++ gdb-7.6.1/gdb/symtab.c	2013-11-09 17:29:21.936727453 +0100
@@ -1260,7 +1260,7 @@ lookup_language_this (const struct langu
    return 1 if the component named NAME from the ultimate target
    structure/union is defined, otherwise, return 0.  */
 
-static int
+int
 check_field (struct type *type, const char *name,
 	     struct field_of_this_result *is_a_field_of_this)
 {
Index: gdb-7.6.1/gdb/symtab.h
===================================================================
--- gdb-7.6.1.orig/gdb/symtab.h	2013-11-09 17:29:19.339729298 +0100
+++ gdb-7.6.1/gdb/symtab.h	2013-11-09 17:27:11.329820268 +0100
@@ -1318,4 +1318,9 @@ void iterate_over_symbols (const struct
 struct cleanup *demangle_for_lookup (const char *name, enum language lang,
 				     const char **result_name);
 
+/* See comment in symtab.c.  */
+
+int check_field (struct type *type, const char *name,
+		 struct field_of_this_result *is_a_field_of_this);
+
 #endif /* !defined(SYMTAB_H) */
Index: gdb-7.6.1/gdb/valops.c
===================================================================
--- gdb-7.6.1.orig/gdb/valops.c	2013-11-09 17:29:19.340729297 +0100
+++ gdb-7.6.1/gdb/valops.c	2013-11-09 17:28:02.417784136 +0100
@@ -3401,10 +3401,35 @@ value_struct_elt_for_reference (struct t
 	    return value_from_longest
 	      (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
 	       offset + (TYPE_FIELD_BITPOS (t, i) >> 3));
-	  else if (noside == EVAL_AVOID_SIDE_EFFECTS)
+	  else if (noside != EVAL_NORMAL)
 	    return allocate_value (TYPE_FIELD_TYPE (t, i));
 	  else
-	    error (_("Cannot reference non-static field \"%s\""), name);
+	    {
+	      /* Try to evaluate NAME as a qualified name with implicit
+		 this pointer.  In this case, attempt to return the
+		 equivalent to `this->*(&TYPE::NAME)'.  */
+	      v = value_of_this_silent (current_language);
+	      if (v != NULL)
+		{
+		  struct value *ptr;
+		  long mem_offset;
+		  struct type *type, *tmp;
+
+		  ptr = value_aggregate_elt (domain, name, NULL, 1, noside);
+		  type = check_typedef (value_type (ptr));
+		  gdb_assert (type != NULL
+			      && TYPE_CODE (type) == TYPE_CODE_MEMBERPTR);
+		  tmp = lookup_pointer_type (TYPE_DOMAIN_TYPE (type));
+		  v = value_cast_pointers (tmp, v, 1);
+		  mem_offset = value_as_long (ptr);
+		  tmp = lookup_pointer_type (TYPE_TARGET_TYPE (type));
+		  result = value_from_pointer (tmp,
+					       value_as_long (v) + mem_offset);
+		  return value_ind (result);
+		}
+
+	      error (_("Cannot reference non-static field \"%s\""), name);
+	    }
 	}
     }
 
Index: gdb-7.6.1/gdb/testsuite/gdb.cp/impl-this.cc
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ gdb-7.6.1/gdb/testsuite/gdb.cp/impl-this.cc	2013-11-09 17:29:21.938727452 +0100
@@ -0,0 +1,96 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2013 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/>.  */
+
+#ifdef DEBUG
+#include <stdio.h>
+#endif
+
+class A
+{
+public:
+  int i;
+  int z;
+  A () : i (1), z (10) {}
+};
+
+class B : public virtual A
+{
+public:
+  int i;
+  B () : i (2) {}
+};
+
+class C : public virtual A
+{
+public:
+  int i;
+  int c;
+  C () : i (3), c (30) {}
+};
+
+class D : public B, public C
+{
+public:
+  int i;
+  int x;
+  D () : i (4), x (40) {}
+
+#ifdef DEBUG
+#define SUM(X)					\
+  do						\
+    {						\
+      sum += (X);				\
+      printf ("" #X " = %d\n", (X));		\
+    }						\
+  while (0)
+#else
+#define SUM(X) sum += (X)
+#endif
+
+int
+f (void)
+  {
+    int sum = 0;
+
+    SUM (i);
+    SUM (D::i);
+    SUM (D::B::i);
+    SUM (B::i);
+    SUM (D::C::i);
+    SUM (C::i);
+    SUM (D::B::A::i);
+    SUM (B::A::i);
+    SUM (A::i);
+    SUM (D::C::A::i);
+    SUM (C::A::i);
+    SUM (D::x);
+    SUM (x);
+    SUM (D::C::c);
+    SUM (C::c);
+    SUM (c);
+
+    return sum;
+  }
+};
+
+int
+main (void)
+{
+  D d;
+
+  return d.f ();
+}
Index: gdb-7.6.1/gdb/testsuite/gdb.cp/impl-this.exp
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ gdb-7.6.1/gdb/testsuite/gdb.cp/impl-this.exp	2013-11-09 17:29:21.939727451 +0100
@@ -0,0 +1,89 @@
+# Copyright 2013 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/>.
+
+# This file is part of the gdb testsuite
+
+# Test expressions which assume an implicit "this" with a qualified
+# name.
+
+if {[skip_cplus_tests]} { continue }
+
+standard_testfile .cc
+
+if {[prepare_for_testing $testfile.exp $testfile $srcfile {debug c++}]} {
+    return -1
+}
+
+# First test expressions when there is no context.
+gdb_test "print i" "No symbol \"i\" in current context."
+gdb_test "print D::i" "Cannot reference non-static field \"i\""
+gdb_test "print D::B::i" "Cannot reference non-static field \"i\""
+gdb_test "print B::i" "Cannot reference non-static field \"i\""
+gdb_test "print D::C::i" "Cannot reference non-static field \"i\""
+gdb_test "print C::i" "Cannot reference non-static field \"i\""
+gdb_test "print D::B::A::i" "Cannot reference non-static field \"i\""
+gdb_test "print B::A::i" "Cannot reference non-static field \"i\""
+gdb_test "print A::i" "Cannot reference non-static field \"i\""
+gdb_test "print D::C::A::i" "Cannot reference non-static field \"i\""
+gdb_test "print C::A::i" "Cannot reference non-static field \"i\""
+gdb_test "print D::x" "Cannot reference non-static field \"x\""
+gdb_test "print x" "No symbol \"x\" in current context."
+gdb_test "print D::C::c" "Cannot reference non-static field \"c\""
+gdb_test "print C::c" "Cannot reference non-static field \"c\""
+gdb_test "print c" "No symbol \"c\" in current context."
+
+# Run to D::f.
+if {![runto_main]} {
+    perror "couldn't run to main"
+    continue
+}
+
+gdb_breakpoint "D::f"
+gdb_continue_to_breakpoint "run to D::f"
+
+# Now test valid expressions in the class hierarchy for D.
+gdb_test "print i" "= 4"
+gdb_test "print D::i" "= 4"
+gdb_test "print D::B::i" "= 2"
+gdb_test "print B::i" "= 2"
+gdb_test "print D::C::i" "= 3"
+gdb_test "print C::i" "= 3"
+gdb_test "print D::B::A::i" "= 1"
+gdb_test "print B::A::i" "= 1"
+gdb_test "print A::i" "= 1"
+gdb_test "print D::C::A::i" "= 1"
+gdb_test "print C::A::i" "= 1"
+gdb_test "print D::x" "= 40"
+gdb_test "print x" "= 40"
+gdb_test "print D::C::c" "= 30"
+gdb_test "print C::c" "= 30"
+gdb_test "print c" "= 30"
+
+# Test some invalid expressions
+gdb_test "print D::B::c" "There is no field named c"
+gdb_test "print D::B::A::c" "There is no field named c"
+gdb_test "print D::C::A::c" "There is no field named c"
+gdb_test "print B::c" "There is no field named c"
+gdb_test "print B::A::c" "There is no field named c"
+gdb_test "print C::A::c" "There is no field named c"
+gdb_test "print D::B::x" "There is no field named x"
+gdb_test "print D::B::A::x" "There is no field named x"
+gdb_test "print B::x" "There is no field named x"
+gdb_test "print B::A::x" "There is no field named x"
+gdb_test "print D::C::x" "There is no field named x"
+gdb_test "print C::x" "There is no field named x"
+gdb_test "print D::C::A::x" "There is no field named x"
+gdb_test "print C::A::x" "There is no field named x"
+