Index: lib/Fuzzer/FuzzerDriver.cpp
===================================================================
--- lib/Fuzzer/FuzzerDriver.cpp
+++ lib/Fuzzer/FuzzerDriver.cpp
@@ -567,7 +567,7 @@
   F->Loop();
 
   if (Flags.verbosity)
-    Printf("Done %d runs in %zd second(s)\n", F->getTotalNumberOfRuns(),
+    Printf("Done %zu runs in %zu second(s)\n", F->getTotalNumberOfRuns(),
            F->secondsSinceProcessStartUp());
   F->PrintFinalStats();
 
Index: lib/Fuzzer/FuzzerLoop.cpp
===================================================================
--- lib/Fuzzer/FuzzerLoop.cpp
+++ lib/Fuzzer/FuzzerLoop.cpp
@@ -344,14 +344,14 @@
       csvHeaderPrinted = true;
       Printf("runs,block_cov,bits,cc_cov,corpus,execs_per_sec,tbms,reason\n");
     }
-    Printf("%zd,%zd,%zd,%zd,%zd,%zd,%s\n", TotalNumberOfRuns,
+    Printf("%zu,%zd,%zd,%zd,%zd,%zd,%s\n", TotalNumberOfRuns,
            MaxCoverage.BlockCoverage, MaxCoverage.CounterBitmapBits,
            MaxCoverage.CallerCalleeCoverage, Corpus.size(), ExecPerSec, Where);
   }
 
   if (!Options.Verbosity)
     return;
-  Printf("#%zd\t%s", TotalNumberOfRuns, Where);
+  Printf("#%zu\t%s", TotalNumberOfRuns, Where);
   if (MaxCoverage.BlockCoverage)
     Printf(" cov: %zd", MaxCoverage.BlockCoverage);
   if (size_t N = TPC.GetTotalPCCoverage())
@@ -390,7 +390,7 @@
     Corpus.PrintStats();
   if (!Options.PrintFinalStats) return;
   size_t ExecPerSec = execPerSec();
-  Printf("stat::number_of_executed_units: %zd\n", TotalNumberOfRuns);
+  Printf("stat::number_of_executed_units: %zu\n", TotalNumberOfRuns);
   Printf("stat::average_exec_per_sec:     %zd\n", ExecPerSec);
   Printf("stat::new_units_added:          %zd\n", NumberOfNewUnitsAdded);
   Printf("stat::slowest_unit_time_sec:    %zd\n", TimeOfLongestUnitInSeconds);