Fix error reporting in the PNaCl bitcode reader.

tools/pnacl-benchmark/pnacl-benchmark.cpp

 //===-- pnacl-benchmark.cpp -----------------------------------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // pnacl-benchmark: various benchmarking tools for the PNaCl LLVM toolchain.
@@ skipping 27 matching lines @@
 
 using namespace llvm;
 
 
 static cl::opt<std::string>
 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
 
 static cl::opt<unsigned>
 NumRuns("num-runs", cl::desc("Number of runs"), cl::init(1));
 
+static cl::opt<bool>
+VerboseErrors(
+    "verbose-parse-errors",
+    cl::desc("Print out more descriptive PNaCl bitcode parse errors"),
+    cl::init(false));
+
 /// Used in a lexical block to measure and report the block's execution time.
 ///
 /// \param N block name
 /// \param InputSize optional size of input operated upon. If given, the
 ///                  throughput will be reported as well in MB/sec.
 class TimingOperationBlock {
 public:
   TimingOperationBlock(StringRef N, size_t InputSize=0)
     : InputSize(InputSize) {
     outs() << "Timing: " << N << "... ";
@@ skipping 137 matching lines @@
     TimingOperationBlock T("Running bitcode analysis", BufSize);
 
     AnalysisDumpOptions DumpOptions;
     AnalyzeBitcodeInBuffer(FileBuf, nulls(), DumpOptions);
   }
 
   // Actual LLVM IR parsing and formation from the bitcode
   {
     TimingOperationBlock T("LLVM IR parsing", BufSize);
     SMDiagnostic Err;
+    raw_ostream *Verbose = VerboseErrors ? &errs() : nullptr;
     Module *M = NaClParseIRFile(InputFilename, PNaClFormat,
-                                Err, getGlobalContext());
+                                Err, Verbose, getGlobalContext());
 
     if (!M) {
       report_fatal_error("Unable to NaClParseIRFile");
     }
   }
 }
 
 int main(int argc, char **argv) {
   sys::PrintStackTraceOnErrorSignal();
   PrettyStackTraceProgram X(argc, argv);
 
   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
   cl::ParseCommandLineOptions(argc, argv, "pnacl-benchmark\n");
 
   for (unsigned i = 0; i < NumRuns; i++) {
     BenchmarkIRParsing();
   }
 
   return 0;
 }