[llvm] r224563 - [Object] Don't crash on empty export lists.

[Juergen Ributzka]

Author: ributzka
Date: Thu Dec 18 20:31:01 2014
New Revision: 224563

URL: http://llvm.org/viewvc/llvm-project?rev=224563&view=rev
Log:
[Object] Don't crash on empty export lists.

Summary: This fixes the exports iterator if the export list is empty.

Reviewers: Bigcheese, kledzik

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D6732

Added:
    llvm/trunk/test/Object/Inputs/macho-no-exports.dylib   (with props)
    llvm/trunk/test/Object/objdump-export-list.test
Modified:
    llvm/trunk/lib/Object/MachOObjectFile.cpp

Modified: llvm/trunk/lib/Object/MachOObjectFile.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Object/MachOObjectFile.cpp?rev=224563&r1=224562&r2=224563&view=diff
==============================================================================
--- llvm/trunk/lib/Object/MachOObjectFile.cpp (original)
+++ llvm/trunk/lib/Object/MachOObjectFile.cpp Thu Dec 18 20:31:01 2014
@@ -1640,7 +1640,10 @@ void ExportEntry::moveNext() {
 iterator_range<export_iterator> 
 MachOObjectFile::exports(ArrayRef<uint8_t> Trie) {
   ExportEntry Start(Trie);
-  Start.moveToFirst();
+  if (Trie.size() == 0)
+    Start.moveToEnd();
+  else
+    Start.moveToFirst();
 
   ExportEntry Finish(Trie);
   Finish.moveToEnd();

Added: llvm/trunk/test/Object/Inputs/macho-no-exports.dylib
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/Inputs/macho-no-exports.dylib?rev=224563&view=auto
==============================================================================
Binary files llvm/trunk/test/Object/Inputs/macho-no-exports.dylib (added) and llvm/trunk/test/Object/Inputs/macho-no-exports.dylib Thu Dec 18 20:31:01 2014 differ

Propchange: llvm/trunk/test/Object/Inputs/macho-no-exports.dylib
------------------------------------------------------------------------------
    svn:executable = *

Added: llvm/trunk/test/Object/objdump-export-list.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/objdump-export-list.test?rev=224563&view=auto
==============================================================================
--- llvm/trunk/test/Object/objdump-export-list.test (added)
+++ llvm/trunk/test/Object/objdump-export-list.test Thu Dec 18 20:31:01 2014
@@ -0,0 +1,4 @@
+RUN: llvm-objdump -exports-trie %p/Inputs/macho-no-exports.dylib | FileCheck %s
+
+; Test that we don't crash with an empty export list.
+CHECK: macho-no-exports.dylib: file format Mach-O 64-bit x86-64