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[PATCH v2] fixed inherit_abstract_dies infinite recursive call


From: linzj <linzj@ucweb.com>

    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 | 7 +++++++
 2 files changed, 15 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..c226a52 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;
@@ -8013,6 +8015,10 @@ process_imported_unit_die (struct die_info *die, struct dwarf2_cu *cu)
 static void
 process_die (struct die_info *die, struct dwarf2_cu *cu)
 {
+  /* Only process those who are not in process.  */
+  if (die->in_process)
+    return;
+  die->in_process = 1;
   switch (die->tag)
     {
     case DW_TAG_padding:
@@ -8100,6 +8106,7 @@ process_die (struct die_info *die, struct dwarf2_cu *cu)
       new_symbol (die, NULL, cu);
       break;
     }
+    die->in_process = 0;
 }
 
 /* DWARF name computation.  */
-- 
1.8.3.2


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