Index: docs/LangRef.rst
===================================================================
--- docs/LangRef.rst
+++ docs/LangRef.rst
@@ -1524,9 +1524,7 @@
     result (or decides to unwind an exception) based strictly on its arguments,
     without dereferencing any pointer arguments or otherwise accessing
     any mutable state (e.g. memory, control registers, etc) visible to
-    caller functions. It does not write through any pointer arguments
-    (including ``byval`` arguments) and never changes any state visible
-    to callers. This means while it cannot unwind exceptions by calling
+    caller functions. This means while it cannot unwind exceptions by calling
     the ``C++`` exception throwing methods (since they write to memory), there may
     be non-``C++`` mechanisms that throw exceptions without writing to LLVM
     visible memory.
Index: lib/IR/Verifier.cpp
===================================================================
--- lib/IR/Verifier.cpp
+++ lib/IR/Verifier.cpp
@@ -1523,12 +1523,6 @@
          "'readnone and readonly' are incompatible!",
          V);
 
-  Assert(!(Attrs.hasAttribute(Attribute::ReadNone) &&
-           Attrs.hasAttribute(Attribute::WriteOnly)),
-         "Attributes "
-         "'readnone and writeonly' are incompatible!",
-         V);
-
   Assert(!(Attrs.hasAttribute(Attribute::ReadOnly) &&
            Attrs.hasAttribute(Attribute::WriteOnly)),
          "Attributes "
@@ -1660,10 +1654,6 @@
            Attrs.hasFnAttribute(Attribute::ReadOnly)),
          "Attributes 'readnone and readonly' are incompatible!", V);
 
-  Assert(!(Attrs.hasFnAttribute(Attribute::ReadNone) &&
-           Attrs.hasFnAttribute(Attribute::WriteOnly)),
-         "Attributes 'readnone and writeonly' are incompatible!", V);
-
   Assert(!(Attrs.hasFnAttribute(Attribute::ReadOnly) &&
            Attrs.hasFnAttribute(Attribute::WriteOnly)),
          "Attributes 'readonly and writeonly' are incompatible!", V);
Index: test/Verifier/writeonly.ll
===================================================================
--- test/Verifier/writeonly.ll
+++ test/Verifier/writeonly.ll
@@ -1,13 +1,7 @@
 ; RUN: not llvm-as %s -o /dev/null 2>&1 | FileCheck %s
 
-declare void @a() readnone writeonly
-; CHECK: Attributes {{.*}} are incompatible
-
 declare void @b() readonly writeonly
 ; CHECK: Attributes {{.*}} are incompatible
 
-declare void @c(i32* readnone writeonly %p)
-; CHECK: Attributes {{.*}} are incompatible
-
 declare void @d(i32* readonly writeonly %p)
 ; CHECK: Attributes {{.*}} are incompatible