Index: llvm/lib/IR/StructuralHash.cpp
===================================================================
--- llvm/lib/IR/StructuralHash.cpp
+++ llvm/lib/IR/StructuralHash.cpp
@@ -58,8 +58,9 @@
   }
 
   void update(const GlobalVariable &GV) {
-    // used/compiler.used don't affect analyses.
-    if (GV.getName() == "llvm.compiler.used" || GV.getName() == "llvm.used")
+    // Declarations and used/compiler.used don't affect analyses.
+    if (GV.isDeclaration() || GV.getName() == "llvm.compiler.used" ||
+        GV.getName() == "llvm.used")
       return;
     hash(23456); // Global header
     hash(GV.getValueType()->getTypeID());
Index: llvm/test/Transforms/StripDeadPrototypes/remove-global-variable-declaration.ll
===================================================================
--- /dev/null
+++ llvm/test/Transforms/StripDeadPrototypes/remove-global-variable-declaration.ll
@@ -0,0 +1,9 @@
+; RUN: opt -passes=strip-dead-prototypes -S -verify-analysis-invalidation < %s | FileCheck %s
+
+; The declaration of the unused global variable @.str should be removed without
+; getting any error from -verify-analysis-invalidation.
+
+; CHECK-NOT: @.str
+
+@.str = external constant [15 x i16]
+