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[PATCH v2] fixed inherit_abstract_dies infinite recursive call
- From: manjian2006 at gmail dot com
- To: gdb-patches at sourceware dot org, tromey at redhat dot com, brobecker at adacore dot com
- Cc: linzj <linzj at ucweb dot com>
- Date: Tue, 21 Jan 2014 18:38:25 +0800
- Subject: [PATCH v2] fixed inherit_abstract_dies infinite recursive call
- Authentication-results: sourceware.org; auth=none
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