[libFuzzer] in fork mode, make sure the child stats are always collected. This should fix the flakiness in fork-ubsan.test

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk/lib/fuzzer@358726 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CMakeLists.txt b/CMakeLists.txt
index aa62995..f473910 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -66,6 +66,7 @@
 endif()
 
 append_list_if(COMPILER_RT_HAS_OMIT_FRAME_POINTER_FLAG -fno-omit-frame-pointer LIBFUZZER_CFLAGS)
+append_list_if(True -fexceptions LIBFUZZER_CFLAGS)
 
 if (CMAKE_CXX_FLAGS MATCHES "fsanitize-coverage")
   list(APPEND LIBFUZZER_CFLAGS -fno-sanitize-coverage=trace-pc-guard,edge,trace-cmp,indirect-calls,8bit-counters)
diff --git a/FuzzerFork.cpp b/FuzzerFork.cpp
index 3d85beb..9d338aa 100644
--- a/FuzzerFork.cpp
+++ b/FuzzerFork.cpp
@@ -150,6 +150,9 @@
   }
 
   void RunOneMergeJob(FuzzJob *Job) {
+    auto Stats = ParseFinalStatsFromLog(Job->LogPath);
+    NumRuns += Stats.number_of_executed_units;
+
     Vector<SizedFile> TempFiles, MergeCandidates;
     // Read all newly created inputs and their feature sets.
     // Choose only those inputs that have new features.
@@ -189,8 +192,6 @@
           PrintPC("  NEW_FUNC: %p %F %L\n", "",
                   TPC.GetNextInstructionPc(TE->PC));
 
-    auto Stats = ParseFinalStatsFromLog(Job->LogPath);
-    NumRuns += Stats.number_of_executed_units;
     if (!FilesToAdd.empty() || Job->ExitCode != 0)
       Printf("#%zd: cov: %zd ft: %zd corp: %zd exec/s %zd "
              "oom/timeout/crash: %zd/%zd/%zd time: %zds\n", NumRuns,