From: Keno Fischer <keno@alumni.harvard.edu>
Date: Thu, 26 Oct 2017 17:31:33 +0000 (+0000)
Subject: [dsymutil] Check AttrInfo.Name validity before using it
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=ea6f05e017653ff7851ffb1e263847cc9e6d7cec;p=llvm

[dsymutil] Check AttrInfo.Name validity before using it

Summary:
This upstreams a patch from the osxcross [1] toolchain.
It appears that llvm-dsymutil crashes at this place during GCC
bootstrap. Adding the check here seems reasonable, since it operates
on arbitrary input DWARF, not necessarily generated by the LLVM
toolchain, and it seems the un-mangled name need not necessarily exist.

Patch by Thomas Pöchtrager

[1] https://github.com/tpoechtrager/osxcross

Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D39336

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316678 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/tools/dsymutil/DwarfLinker.cpp b/tools/dsymutil/DwarfLinker.cpp
index e422bd035cb..b22b7a9dd1a 100644
--- a/tools/dsymutil/DwarfLinker.cpp
+++ b/tools/dsymutil/DwarfLinker.cpp
@@ -2878,7 +2878,8 @@ DIE *DwarfLinker::DIECloner::cloneDIE(
                               Tag == dwarf::DW_TAG_inlined_subroutine);
   } else if (isTypeTag(Tag) && !AttrInfo.IsDeclaration &&
              getDIENames(InputDIE, AttrInfo)) {
-    Unit.addTypeAccelerator(Die, AttrInfo.Name, AttrInfo.NameOffset);
+    if (AttrInfo.Name)
+      Unit.addTypeAccelerator(Die, AttrInfo.Name, AttrInfo.NameOffset);
   }
 
   // Determine whether there are any children that we want to keep.