try to flush stdio in the crash handler

dm/DM.cpp

Index: dm/DM.cpp
diff --git a/dm/DM.cpp b/dm/DM.cpp
index d8421c95b062915d45262904e6c7a6866f28274a..3a7ba77a3dd56867766c5738b6d2a46f52dbc191 100644
--- a/dm/DM.cpp
+++ b/dm/DM.cpp
@@ -185,6 +185,7 @@ static std::atomic<bool> in_signal_handler{false};
             }
             info("\n");
             print_status();
+            fflush(stdout);
         }
         // Execute default exception handler... hopefully, exit.
         return EXCEPTION_EXECUTE_HANDLER;
@@ -214,6 +215,7 @@ static std::atomic<bool> in_signal_handler{false};
                     for (int i = 0; i < count; i++) {
                         info("    %s\n", symbols[i]);
                     }
+                    fflush(stdout);
                 }
                 _Exit(sig);
             });