Index: include/clang/Basic/DiagnosticSemaKinds.td
===================================================================
--- include/clang/Basic/DiagnosticSemaKinds.td
+++ include/clang/Basic/DiagnosticSemaKinds.td
@@ -293,6 +293,9 @@
           "static data member of %2|"
           "field of %2}1">,
   InGroup<Shadow>, DefaultIgnore;
+  
+def error_inoutput_conflict_with_clobber : Error<
+  "asm-specifier for input or output variable conflicts with asm clobber list">;
 
 // C++ using declarations
 def err_using_requires_qualname : Error<
Index: lib/CodeGen/CGStmt.cpp
===================================================================
--- lib/CodeGen/CGStmt.cpp
+++ lib/CodeGen/CGStmt.cpp
@@ -1763,6 +1763,8 @@
   std::string InOutConstraints;
   std::vector<llvm::Value*> InOutArgs;
   std::vector<llvm::Type*> InOutArgTypes;
+  std::vector<std::pair<std::string,clang::SourceLocation> > InputVars;
+  std::vector<std::pair<std::string, clang::SourceLocation> > OutputVars;
 
   // An inline asm can be marked readonly if it meets the following conditions:
   //  - it doesn't have any sideeffects
@@ -1781,6 +1783,7 @@
                                           getTarget());
 
     const Expr *OutExpr = S.getOutputExpr(i);
+    SourceLocation source = OutExpr->getLocStart();
     OutExpr = OutExpr->IgnoreParenNoopCasts(getContext());
 
     OutputConstraint = AddVariableConstraints(OutputConstraint, *OutExpr,
@@ -1859,6 +1862,7 @@
       InOutArgTypes.push_back(Arg->getType());
       InOutArgs.push_back(Arg);
     }
+    OutputVars.push_back(std::pair<std::string,SourceLocation>(OutputConstraint,source));
   }
 
   // If this is a Microsoft-style asm blob, store the return registers (EAX:EDX)
@@ -1877,6 +1881,7 @@
 
   for (unsigned i = 0, e = S.getNumInputs(); i != e; i++) {
     const Expr *InputExpr = S.getInputExpr(i);
+    SourceLocation source = InputExpr->getLocStart();
 
     TargetInfo::ConstraintInfo &Info = InputConstraintInfos[i];
 
@@ -1934,6 +1939,7 @@
     ArgTypes.push_back(Arg->getType());
     Args.push_back(Arg);
     Constraints += InputConstraint;
+    InputVars.push_back(std::pair<std::string, SourceLocation>(InputConstraint, source));
   }
 
   // Append the "input" part of inout constraints last.
@@ -1958,6 +1964,17 @@
     Constraints += "~{";
     Constraints += Clobber;
     Constraints += '}';
+    std::string ClobberP = std::string("{");
+    ClobberP += Clobber;
+    ClobberP += "}";
+    for (std::vector<std::pair<std::string,SourceLocation> >::iterator it = OutputVars.begin(); it != OutputVars.end(); ++it){
+      if (ClobberP == it->first)
+        CGM.getDiags().Report(it->second, diag::error_inoutput_conflict_with_clobber);
+    }
+    for (std::vector<std::pair<std::string, SourceLocation> >::iterator it = InputVars.begin(); it != InputVars.end(); ++it){
+      if (ClobberP == it->first)
+        CGM.getDiags().Report(it->second, diag::error_inoutput_conflict_with_clobber);
+    }
   }
 
   // Add machine specific clobbers