Fix locking for printing error messages.

unittest/IceParseInstsTest.cpp

 //===- unittest/IceParseInstsTest.cpp - test instruction errors -----------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include "llvm/ADT/STLExtras.h"
@@ skipping 45 matching lines @@
             "%p0, i32 @f0);\n"
             "Error(66:4): Invalid relative value id: 100 (Must be <= 4)\n",
             DumpMunger.getLinesWithSubstring("66:4"));
 
   // Show that we get appropriate error when parsing in Subzero.
   IceTest::SubzeroBitcodeMunger Munger(
       BitcodeRecords, array_lengthof(BitcodeRecords), Terminator);
   EXPECT_FALSE(Munger.runTest("Nonexistent call arg"));
   EXPECT_EQ("Error(66:4): Invalid function record: <34 0 4 2 100>\n",
             Munger.getTestResults());
+
+  // Show that we generate a fatal error when not allowing error recovery.
+  Munger.Flags.setAllowErrorRecovery(false);
+  EXPECT_DEATH(
+      Munger.runTest("Nonexistent call arg"),
+      ".*ERROR: Unable to continue.*");
 }
 
 /// Test how we recognize alignments in alloca instructions.
 TEST(IceParseInstsTests, AllocaAlignment) {
   const uint64_t BitcodeRecords[] = {
     1, naclbitc::BLK_CODE_ENTER, naclbitc::MODULE_BLOCK_ID, 2, Terminator,
     1,   naclbitc::BLK_CODE_ENTER, naclbitc::TYPE_BLOCK_ID_NEW, 2, Terminator,
     3,     naclbitc::TYPE_CODE_NUMENTRY, 4, Terminator,
     3,     naclbitc::TYPE_CODE_INTEGER, 32, Terminator,
     3,     naclbitc::TYPE_CODE_VOID, Terminator,
@@ skipping 348 matching lines @@
             Munger.getTestResults());
   EXPECT_FALSE(DumpMunger.runTestForAssembly("Bad Store alignment 30", Align30,
                                              array_lengthof(Align30)));
   EXPECT_EQ(
       "    store float %p1, float* %p0, align 0;\n"
       "Error(62:4): store: Illegal alignment for float. Expects: 1 or 4\n",
       DumpMunger.getLinesWithSubstring("store"));
 }
 
 } // end of anonymous namespace