Index: COFF/Writer.cpp
===================================================================
--- COFF/Writer.cpp
+++ COFF/Writer.cpp
@@ -1158,6 +1158,12 @@
   // against absolute symbols. See applySecIdx in Chunks.cpp..
   DefinedAbsolute::NumOutputSections = OutputSections.size();
 
+  bool OrigExitEarly = errorHandler().ExitEarly;
+  // Don't exit when reaching the error count limit while running multiple
+  // parallel threads; the thread that exits will try to close the output buffer
+  // that other threads still may be touching.
+  errorHandler().ExitEarly = false;
+
   uint8_t *Buf = Buffer->getBufferStart();
   for (OutputSection *Sec : OutputSections) {
     uint8_t *SecBuf = Buf + Sec->getFileOff();
@@ -1169,6 +1175,11 @@
     for_each(parallel::par, Sec->getChunks().begin(), Sec->getChunks().end(),
              [&](Chunk *C) { C->writeTo(SecBuf); });
   }
+
+  errorHandler().ExitEarly = OrigExitEarly;
+  if (errorHandler().ExitEarly &&
+      errorHandler().ErrorCount >= errorHandler().ErrorLimit)
+    exitLld(1);
 }
 
 void Writer::writeBuildId() {