[binutils-gdb] Fix failure to find member of a typedef base class

[Weimin Pan <wmpan at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=bf2977b5f3d25779cdc06ba79c05244d70bd8b59

commit bf2977b5f3d25779cdc06ba79c05244d70bd8b59
Author: Weimin Pan <weimin.pan@oracle.com>
Date:   Mon Jun 18 21:15:13 2018 +0000

    Fix failure to find member of a typedef base class
    
    The test case below demonstrates the problem, as described in this PR's Comment 5:
    
    typedef struct {
            int x;
    } A;
    
    struct C : A {
            int y;
    };
    
    int main()
    {
            C c;
            return 55;
    }
    
    $ gdb a.out
    (gdb) ptype C::x
    Internal error: non-aggregate type to value_struct_elt_for_reference
    
    In value_struct_elt_for_reference(), need to call check_typedef() on
    the aggregate type to handle the case of *curtype being ptr->typedef.
    
    Tested on x86_64-linux. No regressions.

Diff:
---
 gdb/ChangeLog                         |  6 ++++++
 gdb/testsuite/ChangeLog               |  8 +++++++
 gdb/testsuite/gdb.cp/typedef-base.cc  | 30 +++++++++++++++++++++++++++
 gdb/testsuite/gdb.cp/typedef-base.exp | 39 +++++++++++++++++++++++++++++++++++
 gdb/valops.c                          |  2 +-
 5 files changed, 84 insertions(+), 1 deletion(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 4fc6cf5..7b108bf 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -970,6 +970,12 @@
 	* symfile.c (addr_info_make_relative): Likewise.
 	* thread.c (value_in_thread_stack_temporaries): Likewise.
 
+2018-06-12  Weimin Pan  <weimin.pan@oracle.com>
+
+	PR gdb/16841
+	* valops.c (value_struct_elt_for_reference): Call check_typedef on
+	aggregate type to get its real type before accessing it.
+
 2018-05-29  Weimin Pan  <weimin.pan@oracle.com>
 
 	* minsyms.h (lookup_minimal_symbol_and_objfile): Remove declaration.
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 173ee2b..a812061 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,4 @@
+<<<<<<< HEAD
 2018-06-18  Tom de Vries  <tdevries@suse.de>
 
 	* gdb.ada/bp_inlined_func.exp: Allow 5 breakpoint locations.
@@ -95,6 +96,13 @@
 
 	* gdb.base/endian.exp: New test.
 	* gdb.base/endian.c: New test source.
+=======
+2018-06-12  Weimin Pan  <weimin.pan@oracle.com>
+
+	PR gdb/16841
+	* gdb.cp/typedef-base.cc: New file.
+	* gdb.cp/typedef-base.exp: New file.
+>>>>>>> Fix failure to find member of a typedef base class
 
 2018-05-24  Andrew Burgess  <andrew.burgess@embecosm.com>
 
diff --git a/gdb/testsuite/gdb.cp/typedef-base.cc b/gdb/testsuite/gdb.cp/typedef-base.cc
new file mode 100644
index 0000000..f54ed10
--- /dev/null
+++ b/gdb/testsuite/gdb.cp/typedef-base.cc
@@ -0,0 +1,30 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2018 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/>.  */
+
+typedef struct {
+  int x;
+} A;
+
+struct C : A {
+  int y;
+};
+
+int main()
+{
+  C c;
+  return 55;
+}
diff --git a/gdb/testsuite/gdb.cp/typedef-base.exp b/gdb/testsuite/gdb.cp/typedef-base.exp
new file mode 100644
index 0000000..2e8ca8c
--- /dev/null
+++ b/gdb/testsuite/gdb.cp/typedef-base.exp
@@ -0,0 +1,39 @@
+# Copyright 2018 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/>.
+#
+# Make sure that inheritance through a typedef is well handled.
+
+if { [skip_cplus_tests] } { continue }
+
+standard_testfile .cc
+
+if [get_compiler_info "c++"] {
+    return -1
+}
+
+if {[prepare_for_testing "failed to prepare" $testfile $srcfile {debug c++}]} {
+    return -1
+}
+
+clean_restart $testfile
+
+if ![runto_main] {
+    untested "could not run to main"
+    return -1
+}
+
+gdb_test "ptype C::x" \
+         "type = int" \
+         "ptype typedef base struct member"
diff --git a/gdb/valops.c b/gdb/valops.c
index 9337457..9bdbf22 100644
--- a/gdb/valops.c
+++ b/gdb/valops.c
@@ -3343,7 +3343,7 @@ value_struct_elt_for_reference (struct type *domain, int offset,
 				int want_address,
 				enum noside noside)
 {
-  struct type *t = curtype;
+  struct type *t = check_typedef (curtype);
   int i;
   struct value *v, *result;