Index: compiler-rt/lib/fuzzer/FuzzerLoop.cpp
===================================================================
--- compiler-rt/lib/fuzzer/FuzzerLoop.cpp
+++ compiler-rt/lib/fuzzer/FuzzerLoop.cpp
@@ -120,12 +120,21 @@
   }
 }
 
+static void PrintErrorPrefix() {
+  Printf("==%lu== ERROR: libFuzzer: ", GetPid());
+}
+
+static void PrintError(const char *Message) {
+  PrintErrorPrefix();
+  Printf("%s\n", Message);
+}
+
 // Crash on a single malloc that exceeds the rss limit.
 void Fuzzer::HandleMalloc(size_t Size) {
   if (!Options.MallocLimitMb || (Size >> 20) < (size_t)Options.MallocLimitMb)
     return;
-  Printf("==%d== ERROR: libFuzzer: out-of-memory (malloc(%zd))\n", GetPid(),
-         Size);
+  PrintErrorPrefix();
+  Printf("out-of-memory (malloc(%zd))\n", Size);
   Printf("   To change the out-of-memory limit use -rss_limit_mb=<N>\n\n");
   PrintStackTrace();
   DumpCurrentUnit("oom-");
@@ -189,6 +198,7 @@
 
 NO_SANITIZE_MEMORY
 void Fuzzer::DeathCallback() {
+  PrintError("sanitizer terminated fuzz target");
   DumpCurrentUnit("crash-");
   PrintFinalStats();
 }
@@ -220,7 +230,7 @@
 }
 
 void Fuzzer::StaticFileSizeExceedCallback() {
-  Printf("==%lu== ERROR: libFuzzer: file size exceeded\n", GetPid());
+  PrintError("file size exceeded");
   exit(1);
 }
 
@@ -228,7 +238,7 @@
   if (EF->__sanitizer_acquire_crash_state &&
       !EF->__sanitizer_acquire_crash_state())
     return;
-  Printf("==%lu== ERROR: libFuzzer: deadly signal\n", GetPid());
+  PrintError("deadly signal");
   PrintStackTrace();
   Printf("NOTE: libFuzzer has rudimentary signal handlers.\n"
          "      Combine libFuzzer with AddressSanitizer or similar for better "
@@ -245,7 +255,7 @@
   if (EF->__sanitizer_acquire_crash_state &&
       !EF->__sanitizer_acquire_crash_state())
     return;
-  Printf("==%lu== ERROR: libFuzzer: fuzz target exited\n", GetPid());
+  PrintError("fuzz target exited");
   PrintStackTrace();
   Printf("SUMMARY: libFuzzer: fuzz target exited\n");
   DumpCurrentUnit("crash-");
@@ -295,8 +305,8 @@
     Printf("       and the timeout value is %d (use -timeout=N to change)\n",
            Options.UnitTimeoutSec);
     DumpCurrentUnit("timeout-");
-    Printf("==%lu== ERROR: libFuzzer: timeout after %d seconds\n", GetPid(),
-           Seconds);
+    PrintErrorPrefix();
+    Printf("timeout after %d seconds\n", Seconds);
     PrintStackTrace();
     Printf("SUMMARY: libFuzzer: timeout\n");
     PrintFinalStats();
@@ -308,9 +318,8 @@
   if (EF->__sanitizer_acquire_crash_state &&
       !EF->__sanitizer_acquire_crash_state())
     return;
-  Printf(
-      "==%lu== ERROR: libFuzzer: out-of-memory (used: %zdMb; limit: %zdMb)\n",
-      GetPid(), GetPeakRSSMb(), Options.RssLimitMb);
+  PrintErrorPrefix();
+  Printf("out-of-memory (used: %zdMb; limit: %zdMb)\n", GetPeakRSSMb(), Options.RssLimitMb);
   Printf("   To change the out-of-memory limit use -rss_limit_mb=<N>\n\n");
   PrintMemoryProfile();
   DumpCurrentUnit("oom-");
@@ -513,10 +522,9 @@
 }
 
 void Fuzzer::CrashOnOverwrittenData() {
-  Printf("==%d== ERROR: libFuzzer: fuzz target overwrites it's const input\n",
-         GetPid());
+  PrintError("fuzz target overwrites its const input");
   DumpCurrentUnit("crash-");
-  Printf("SUMMARY: libFuzzer: out-of-memory\n");
+  Printf("SUMMARY: libFuzzer: input overwritten\n");
   _Exit(Options.ErrorExitCode); // Stop right now.
 }