[libcxxabi] r256322 - Fix PR25898 - Check for incomplete pointers types in can_catch(...)

[Eric Fiselier via cfe-commits]

Author: ericwf
Date: Wed Dec 23 00:35:25 2015
New Revision: 256322

URL: http://llvm.org/viewvc/llvm-project?rev=256322&view=rev
Log:
Fix PR25898 - Check for incomplete pointers types in can_catch(...)

Added:
    libcxxabi/trunk/test/incomplete_type.sh.cpp
Modified:
    libcxxabi/trunk/src/private_typeinfo.cpp

Modified: libcxxabi/trunk/src/private_typeinfo.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/private_typeinfo.cpp?rev=256322&r1=256321&r2=256322&view=diff
==============================================================================
--- libcxxabi/trunk/src/private_typeinfo.cpp (original)
+++ libcxxabi/trunk/src/private_typeinfo.cpp Wed Dec 23 00:35:25 2015
@@ -34,9 +34,12 @@
 // 
 // _LIBCXX_DYNAMIC_FALLBACK is currently off by default.
 
+
+#include <string.h>
+
+
 #ifdef _LIBCXX_DYNAMIC_FALLBACK
 #include "abort_message.h"
-#include <string.h>
 #include <sys/syslog.h>
 #endif
 
@@ -57,31 +60,19 @@ namespace __cxxabiv1
 
 #pragma GCC visibility push(hidden)
 
-#ifdef _LIBCXX_DYNAMIC_FALLBACK
-
 inline
 bool
 is_equal(const std::type_info* x, const std::type_info* y, bool use_strcmp)
 {
+#ifndef _WIN32
     if (!use_strcmp)
         return x == y;
     return strcmp(x->name(), y->name()) == 0;
-}
-
-#else  // !_LIBCXX_DYNAMIC_FALLBACK
-
-inline
-bool
-is_equal(const std::type_info* x, const std::type_info* y, bool)
-{
-#ifndef _WIN32
-    return x == y;
 #else
     return (x == y) || (strcmp(x->name(), y->name()) == 0);
-#endif    
+#endif
 }
 
-#endif  // _LIBCXX_DYNAMIC_FALLBACK
 
 // __shim_type_info
 
@@ -351,8 +342,17 @@ bool
 __pbase_type_info::can_catch(const __shim_type_info* thrown_type,
                              void*&) const
 {
-    return is_equal(this, thrown_type, false) ||
-           is_equal(thrown_type, &typeid(std::nullptr_t), false);
+    if (is_equal(thrown_type, &typeid(std::nullptr_t), false)) return true;
+    bool use_strcmp = this->__flags & (__incomplete_class_mask |
+                                       __incomplete_mask);
+    if (!use_strcmp) {
+        const __pbase_type_info* thrown_pbase = dynamic_cast<const __pbase_type_info*>(
+                thrown_type);
+        if (!thrown_pbase) return false;
+        use_strcmp = thrown_pbase->__flags & (__incomplete_class_mask |
+                                              __incomplete_mask);
+    }
+    return is_equal(this, thrown_type, use_strcmp);
 }
 
 #ifdef __clang__

Added: libcxxabi/trunk/test/incomplete_type.sh.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/test/incomplete_type.sh.cpp?rev=256322&view=auto
==============================================================================
--- libcxxabi/trunk/test/incomplete_type.sh.cpp (added)
+++ libcxxabi/trunk/test/incomplete_type.sh.cpp Wed Dec 23 00:35:25 2015
@@ -0,0 +1,83 @@
+//===------------------------- incomplete_type.cpp --------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// http://mentorembedded.github.io/cxx-abi/abi.html#rtti-layout
+
+// Two abi::__pbase_type_info objects can always be compared for equality
+// (i.e. of the types represented) or ordering by comparison of their name
+// NTBS addresses. In addition, unless either or both have either of the
+// incomplete flags set, equality can be tested by comparing the type_info
+// addresses.
+
+// RUN: %cxx %compile_flags -c %s -o %t.one.o
+// RUN: %cxx %compile_flags -c %s -o %t.two.o -DTU_ONE
+// RUN: %cxx %link_flags -o %t.exe %t.one.o %t.two.o
+// RUN: %t.exe
+
+#include <stdio.h>
+#include <cassert>
+#include <typeinfo>
+
+struct NeverDefined;
+void ThrowNeverDefined();
+
+struct IncompleteAtThrow;
+void ThrowIncomplete();
+std::type_info const& ReturnTypeInfoIncomplete();
+
+struct CompleteAtThrow;
+void ThrowComplete();
+std::type_info const& ReturnTypeInfoComplete();
+
+void ThrowNullptr();
+
+#ifndef TU_ONE
+
+void ThrowNeverDefined() { throw (int NeverDefined::*)nullptr; }
+
+void ThrowIncomplete() { throw (int IncompleteAtThrow::*)nullptr; }
+std::type_info const& ReturnTypeInfoIncomplete() { return typeid(int IncompleteAtThrow::*); }
+
+struct CompleteAtThrow {};
+void ThrowComplete() { throw (int CompleteAtThrow::*)nullptr; }
+std::type_info const& ReturnTypeInfoComplete() { return typeid(int CompleteAtThrow::*); }
+
+void ThrowNullptr() { throw nullptr; }
+
+#else
+
+struct IncompleteAtThrow {};
+
+int main() {
+  assert(ReturnTypeInfoIncomplete() != typeid(int IncompleteAtThrow::*));
+  try {
+    ThrowIncomplete();
+  } catch (int IncompleteAtThrow::*) {}
+
+  assert(ReturnTypeInfoComplete() != typeid(int CompleteAtThrow::*));
+  try {
+    ThrowComplete();
+  } catch (int CompleteAtThrow::*) {}
+
+#if __cplusplus >= 201103L
+  // Catch nullptr as complete type
+  try {
+    ThrowNullptr();
+  } catch (int IncompleteAtThrow::*) {}
+
+  // Catch nullptr as an incomplete type
+  try {
+    ThrowNullptr();
+  } catch (int CompleteAtThrow::*) {}
+  // Catch nullptr as a type that is never complete.
+  try {
+    ThrowNeverDefined();
+  } catch (int NeverDefined::*) {}
+#endif
+}
+#endif