diff --git a/llvm/lib/AsmParser/LLParser.cpp b/llvm/lib/AsmParser/LLParser.cpp
--- a/llvm/lib/AsmParser/LLParser.cpp
+++ b/llvm/lib/AsmParser/LLParser.cpp
@@ -2597,6 +2597,8 @@
         return tokError("basic block pointers are invalid");
       if (Result->isVoidTy())
         return tokError("pointers to void are invalid - use i8* instead");
+      if (Result->isOpaquePointerTy())
+        return tokError("ptr* is invalid - use ptr instead");
       if (!PointerType::isValidElementType(Result))
         return tokError("pointer to this type is invalid");
       Result = PointerType::getUnqual(Result);
diff --git a/llvm/test/Assembler/invalid-opaque-ptr-addrspace.ll b/llvm/test/Assembler/invalid-opaque-ptr-addrspace.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Assembler/invalid-opaque-ptr-addrspace.ll
@@ -0,0 +1,7 @@
+; RUN: not llvm-as < %s -disable-output 2>&1 | FileCheck %s
+
+; CHECK: ptr* is invalid - use ptr instead
+define void @f(ptr addrspace(3) %a) {
+    %b = bitcast ptr addrspace(3) %a to ptr addrspace(3)*
+    ret void
+}
diff --git a/llvm/test/Assembler/invalid-opaque-ptr.ll b/llvm/test/Assembler/invalid-opaque-ptr.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Assembler/invalid-opaque-ptr.ll
@@ -0,0 +1,7 @@
+; RUN: not llvm-as < %s -disable-output 2>&1 | FileCheck %s
+
+; CHECK: ptr* is invalid - use ptr instead
+define void @f(ptr %a) {
+    %b = bitcast ptr %a to ptr*
+    ret void
+}