add todo for ALLOW_LLVM_CL

src/IceBuildDefs.h

 //===- subzero/src/IceBuildDefs.h - Translator build defines ----*- C++ -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 59 matching lines @@
  if you don't build that variant, you don't even know if the code would
  compile unless you build with that variant.
 
   **/
 
 namespace BuildDefs {
 
 // The ALLOW_* etc. symbols must be #defined to zero or non-zero.
 constexpr bool dump() { return ALLOW_DUMP; }
 /// Return true if ALLOW_LLVM_CL is defined as a non-zero value
+// TODO(stichnot): this ALLOW_LLVM_CL is a TBD option which will
+// allow for replacement of llvm:cl command line processor with a
+// smaller footprint version for Subzero.
 constexpr bool llvmCl() { return ALLOW_LLVM_CL; }
 /// Return true if ALLOW_LLVM_IR is defined as a non-zero value
 constexpr bool llvmIr() { return ALLOW_LLVM_IR; }
 /// Return true if ALLOW_LLVM_IR_AS_INPUT is defined as a non-zero value
 constexpr bool llvmIrAsInput() { return ALLOW_LLVM_IR_AS_INPUT; }
 /// Return true if ALLOW_MINIMAL_BUILD is defined as a non-zero value
 constexpr bool minimal() { return ALLOW_MINIMAL_BUILD; }
 
 /// Return true if NDEBUG is defined
 constexpr bool asserts() {
@@ skipping 19 matching lines @@
   return true;
 #else  // !ALLOW_EXTRA_VALIDATION
   return false;
 #endif // !ALLOW_EXTRA_VALIDATION
 }
 
 } // end of namespace BuildDefs
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICEBUILDDEFS_H