[lldb/Symbol] Fix null-deref in TypeList::Dump

medismailben · medismailben · commit 564b8a7be606 · 2022-08-17T14:36:59.000-07:00
This patch should just a crash caused by a null pointer dereferencing
when dumping a type. It makes sure that the pointer is valid.

rdar://97455134

Signed-off-by: Med Ismail Bennani &lt;medismail.bennani@gmail.com&gt;
diff --git a/lldb/source/Symbol/TypeList.cpp b/lldb/source/Symbol/TypeList.cpp
@@ -92,9 +92,9 @@ void TypeList::ForEach(
 }
 
 void TypeList::Dump(Stream *s, bool show_context) {
-  for (iterator pos = m_types.begin(), end = m_types.end(); pos != end; ++pos) {
-    pos->get()->Dump(s, show_context);
-  }
+  for (iterator pos = m_types.begin(), end = m_types.end(); pos != end; ++pos)
+    if (Type *t = pos->get())
+      t->Dump(s, show_context);
 }
 
 void TypeList::RemoveMismatchedTypes(const char *qualified_typename,

Original file line number	Diff line number	Diff line change
`@@ -92,9 +92,9 @@ void TypeList::ForEach(`
`92`	`92`	`}`
`93`	`93`
`94`	`94`	`void TypeList::Dump(Stream *s, bool show_context) {`
`95`		`- for (iterator pos = m_types.begin(), end = m_types.end(); pos != end; ++pos) {`
`96`		`- pos->get()->Dump(s, show_context);`
`97`		`- }`
	`95`	`+ for (iterator pos = m_types.begin(), end = m_types.end(); pos != end; ++pos)`
	`96`	`+ if (Type *t = pos->get())`
	`97`	`+ t->Dump(s, show_context);`
`98`	`98`	`}`
`99`	`99`
`100`	`100`	`void TypeList::RemoveMismatchedTypes(const char *qualified_typename,`