From: Sergio Durigan Junior <sergiodj@redhat.com>

Subject: [PATCH] Fix for PR c++/15203 and PR c++/15210
Date: Sat, 09 Mar 2013 02:50:49 -0300 (5 days, 4 hours, 57 minutes ago)
Message-ID: <m3a9qdnmti.fsf@redhat.com>

Hi,

This bug was reported internally at our Bugzilla, along with a proposed
fix.  After talking to Keith about it, he investigated and came up with
another patch needed to really fix the issue on CVS HEAD.

The first part of the fix is the patch to cp-namespace.c.  It handles
the case when we are accessing a static variable inside a function
(inside a class) by the full linespec (is it right, Keith?).  E.g.:

    class foo
    {
    public:
        int bar()
        {
            static int var = 0;
        }
    };

And then, printing the value of `var':

    (gdb) print 'foo::bar()::var'

GDB would fall in an internal_error:

    gdb/cp-namespace.c:816: internal-error: cp_lookup_nested_symbol called on a non-aggregate type.

This is because `cp_lookup_nested_symbol' is not handling the case when
TYPE_CODE is either _FUNC or _METHOD.  This patch fixes it by returning
NULL in this case.

The second part of the fix is the patch to elfread.c.  It is needed
because the BSF_GNU_UNIQUE flag was added to some symbols in
<http://sourceware.org/ml/binutils/2009-06/msg00016.html>.  Because of
that, (still) the command:

    (gdb) print 'foo::bar()::var'

where `var' is a static variable returns:

    "No symbol "foo::bar()::var" in current context."

So with the second patch applied the command finally DTRT:

    (gdb) print 'foo::bar()::var'
    $1 = 0

This may not be the ideal solution, according to Keith it would be good
to implement productions on c-exp.y in order to recognize
CLASS::FUNCTION::VARIABLE, but it is a solution which works with what we
have today.

I regtested it in Fedora 17 x86_64 with -m64 and -m32, including
gdbserver, without regressions.

gdb/:
2013-03-14  Keith Seitz  <keiths@redhat.com>
	    Alan Matsuoka  <alanm@redhat.com>

	PR c++/15203
	PR c++/15210
	* cp-namespace.c (cp_lookup_nested_symbol): Handle TYPE_CODE_FUNC and
	TYPE_CODE_METHOD.
	* elfread.c (elf_symtab_read): Handle BSF_GNU_UNIQUE for certain
	symbols.

gdb/testsuite/:
2013-03-14  Sergio Durigan Junior  <sergiodj@redhat.com>

	PR c++/15203
	PR c++/15210
	* gdb.cp/m-static.cc (keepalive_int): New function.
	(gnu_obj_1::method): New variable `sintvar', call `keepalive_int'.
	* gdb.cp/m-static.exp: New test for `sintvar'.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 4d608f5..2d911aa 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,13 @@
+2013-03-14  Keith Seitz  <keiths@redhat.com>
+           Alan Matsuoka  <alanm@redhat.com>
+
+       PR c++/15203
+       PR c++/15210
+       * cp-namespace.c (cp_lookup_nested_symbol): Handle TYPE_CODE_FUNC and
+       TYPE_CODE_METHOD.
+       * elfread.c (elf_symtab_read): Handle BSF_GNU_UNIQUE for certain
+       symbols.
+
 2013-03-14  Yao Qi  <yao@codesourcery.com>
 
        * tracepoint.c (tfile_write_status): Write 'stop_desc' of trace

diff --git a/gdb/cp-namespace.c b/gdb/cp-namespace.c
index 279021e..add4ccb 100644 (file)
--- a/gdb/cp-namespace.c
+++ b/gdb/cp-namespace.c
@@ -812,6 +812,11 @@ cp_lookup_nested_symbol (struct type *parent_type,
           base classes.  */
        return find_symbol_in_baseclass (parent_type, nested_name, block);
       }
+
+    case TYPE_CODE_FUNC:
+    case TYPE_CODE_METHOD:
+      return NULL;
+
     default:
       internal_error (__FILE__, __LINE__,
                      _("cp_lookup_nested_symbol called "

diff --git a/gdb/elfread.c b/gdb/elfread.c
index 6ab3a6a..14952b8 100644 (file)
--- a/gdb/elfread.c
+++ b/gdb/elfread.c
@@ -357,7 +357,8 @@ elf_symtab_read (struct objfile *objfile, int type,
        }
       else if (sym->flags & BSF_SECTION_SYM)
        continue;
-      else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK))
+      else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK
+                            | BSF_GNU_UNIQUE))
        {
          struct minimal_symbol *msym;
 
@@ -413,7 +414,7 @@ elf_symtab_read (struct objfile *objfile, int type,
            }
          else if (sym->section->flags & SEC_CODE)
            {
-             if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
+             if (sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_GNU_UNIQUE))
                {
                  if (sym->flags & BSF_GNU_INDIRECT_FUNCTION)
                    ms_type = mst_text_gnu_ifunc;
@@ -443,7 +444,7 @@ elf_symtab_read (struct objfile *objfile, int type,
            }
          else if (sym->section->flags & SEC_ALLOC)
            {
-             if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
+             if (sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_GNU_UNIQUE))
                {
                  if (sym->section->flags & SEC_LOAD)
                    {

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index f4863a1..8dac760 100644 (file)
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2013-03-14  Sergio Durigan Junior  <sergiodj@redhat.com>
+
+       PR c++/15203
+       PR c++/15210
+       * gdb.cp/m-static.cc (keepalive_int): New function.
+       (gnu_obj_1::method): New variable `sintvar', call `keepalive_int'.
+       * gdb.cp/m-static.exp: New test for `sintvar'.
+
 2013-03-14  Yao Qi  <yao@codesourcery.com>
 
        * gdb.trace/tstatus.exp (run_trace_experiment): Save the output

diff --git a/gdb/testsuite/gdb.cp/m-static.cc b/gdb/testsuite/gdb.cp/m-static.cc
index 8472988..eadbdfc 100644 (file)
--- a/gdb/testsuite/gdb.cp/m-static.cc
+++ b/gdb/testsuite/gdb.cp/m-static.cc
@@ -3,6 +3,7 @@
 enum region { oriental, egyptian, greek, etruscan, roman };
 
 void keepalive(bool *var) { }
+void keepalive_int (int *var) { }
 
 // Test one.
 class gnu_obj_1
@@ -21,8 +22,11 @@ public:
 
   long method ()
   {
+    static int sintvar = 4;
     static bool svar = true;
+
     keepalive (&svar);
+    keepalive_int (&sintvar);
     return key2;
   }
 };

diff --git a/gdb/testsuite/gdb.cp/m-static.exp b/gdb/testsuite/gdb.cp/m-static.exp
index ae4b2ad..5d1cb8b 100644 (file)
--- a/gdb/testsuite/gdb.cp/m-static.exp
+++ b/gdb/testsuite/gdb.cp/m-static.exp
@@ -52,6 +52,11 @@ gdb_continue_to_breakpoint "end of constructors"
 
 # One.
 
+# simple object, static const int, accessing via 'class::method::variable'
+# Regression test for PR c++/15203 and PR c++/15210
+gdb_test "print 'gnu_obj_1::method()::sintvar'" "\\$\[0-9\]+ = 4" \
+    "simple object, static const int, accessing via 'class::method::variable"
+
 # simple object, static const bool
 gdb_test "print test1.test" "\\$\[0-9\]* = true" "simple object, static const bool"