Fix verifier for GlobalAliases to avoid recursing into global initializers.

The verifier follows GlobalAlias operands so that it can detect cycles of
alias definitions. It was doing this in a way that caused it to also recurse
through initializers for the GlobalValue aliasees, and it would fail when
an initializer refers to a global that is a declaration and not a definition.
This patch causes it to stop recursing when it hits a global definition.
<rdar://problem/17277451>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210734 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 0 deletions

diff --git a/lib/IR/Verifier.cpp b/lib/IR/Verifier.cpp
index b66bd06401..d1c7f7d25c 100644
--- a/lib/IR/Verifier.cpp
+++ b/lib/IR/Verifier.cpp
@@ -493,6 +493,10 @@ void Verifier::visitAliaseeSubExpr(SmallPtrSet<const GlobalAlias *, 4> &Visited,
 
       Assert1(!GA2->mayBeOverridden(), "Alias cannot point to a weak alias",
               &GA);
+    } else {
+      // Only continue verifying subexpressions of GlobalAliases.
+      // Do not recurse into global initializers.
+      return;
     }
   }