[PATCH V3] fixed inherit_abstract_dies infinite recursive call

[manjian2006@gmail.com]

From: linzj <linzj@ucweb.com>

    Reset the die's in_process bit using cleanup facility.
>>    ChangeLog added.
>>    Please Joel Brobecker <brobecker@adacore.com> helps with the testcases.
>> >>     The c++ code causing the problem is:
>> >> 
>> >>         // Integer variants of certain metrics, used for HTML rendering.
>> >>         int ascent(FontBaseline baselineType = AlphabeticBaseline) const
>> >>         {
>> >>             if (baselineType == AlphabeticBaseline)
>> >>                 return lroundf(m_ascent);
>> >>             return height() - height() / 2;
>> >>         }
>> >> 
>> >>         int height(FontBaseline baselineType = AlphabeticBaseline) const
>> >>         {
>> >>             return ascent(baselineType) + descent(baselineType);
>> >>         }
>> >> 
>> >>     As you can see,ascent(0x5816d55) calls height(0x5812c1b),and height calls
>> >>     ascent(0x5816d55) recursivly.And the compiler  generates these dwarf code
>> >>     representing this relationship preciously.
>> >> 
>> >>     A dwarf die may have the following relationship:
>> >>     564860c<-----------------------------
>> >>       |                                 |
>> >>       |(abstract origin)                |
>> >>       |                                 |
>> >>       V                                 |
>> >>     5816d55                             | (abstract origin)
>> >>       |                                 |
>> >>       |(child)                          |
>> >>       |                                 |
>> >>       V                                 |
>> >>       ...                               |
>> >>     5812c34------------------------------
>> >>     So inherit_abstract_dies may results in infinite recursive call.
>> >>     A bit field call in_process has been add to struct die_info to fix this problem.
>> >>     process_die would first check if a die is in processing state, if so,just return.
>> >>     Then in_process bit is set.Before process_die returns,this bit field is unset.
---
 ChangeLog        |  8 ++++++++
 gdb/dwarf2read.c | 19 +++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 9b1cbfa..c17af8d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2013-01-20  lin Zuojian  <manjian2006@gmail.com>
+	* gdb/dwarf2read.c(struct die_info): Add a
+	bit to form a bitmap to avoid visit twice
+	when process_die.
+	* gdb/dwarf2read.c(process_die): Test in_process
+	bit to avoid visit twice.Set in_process bit 
+	before doing actual jobs.Unset in_process bit
+	before process_die returns.
 2013-12-19  Keven Boell  <keven.boell@intel.com>
 
 	* cp-namespace.c (cp_lookup_nested_symbol): Enable
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 7ca527d..cf27283 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -1224,6 +1224,8 @@ struct die_info
     /* True if we're presently building the full type name for the
        type derived from this DIE.  */
     unsigned char building_fullname : 1;
+    /* True if this die is in process.  */
+    unsigned char in_process : 1;
 
     /* Abbrev number */
     unsigned int abbrev;
@@ -8008,11 +8010,27 @@ process_imported_unit_die (struct die_info *die, struct dwarf2_cu *cu)
     }
 }
 
+/* Reset the in_process bit of a die.  */
+static void
+reset_die_in_process(void *arg)
+{
+  struct die_info *die = arg;
+  die->in_process = 0;
+}
+
 /* Process a die and its children.  */
 
 static void
 process_die (struct die_info *die, struct dwarf2_cu *cu)
 {
+  /* The in process bit of a die's cleanup.  */
+  struct cleanup * in_process;
+
+  /* Only process those who are not in process.  */
+  if (die->in_process)
+    return;
+  die->in_process = 1;
+  in_process = make_cleanup(reset_die_in_process,die);
   switch (die->tag)
     {
     case DW_TAG_padding:
@@ -8100,6 +8118,7 @@ process_die (struct die_info *die, struct dwarf2_cu *cu)
       new_symbol (die, NULL, cu);
       break;
     }
+    do_cleanups(in_process);
 }
 \f
 /* DWARF name computation.  */
-- 
1.8.3.2