diff --git a/lldb/source/Utility/ReproducerInstrumentation.cpp b/lldb/source/Utility/ReproducerInstrumentation.cpp
index 473786ef4d3e..0b74acaacb7e 100644
--- a/lldb/source/Utility/ReproducerInstrumentation.cpp
+++ b/lldb/source/Utility/ReproducerInstrumentation.cpp
@@ -8,6 +8,7 @@
 
 #include "lldb/Utility/ReproducerInstrumentation.h"
 #include "lldb/Utility/Reproducer.h"
+#include <stdio.h>
 
 using namespace lldb_private;
 using namespace lldb_private::repro;
@@ -47,6 +48,10 @@ bool Registry::Replay(llvm::StringRef buffer) {
   Log *log = GetLogIfAllCategoriesSet(LIBLLDB_LOG_API);
 #endif
 
+  // Disable buffering stdout so that we approximate the way things get flushed
+  // during an interactive session.
+  setvbuf(stdout, nullptr, _IONBF, 0);
+
   Deserializer deserializer(buffer);
   while (deserializer.HasData(1)) {
     unsigned id = deserializer.Deserialize<unsigned>();