diff --git a/test/test-main.cc b/test/test-main.cc
index f4f2e789..036394cd 100644
--- a/test/test-main.cc
+++ b/test/test-main.cc
@@ -28,11 +28,17 @@
 #include <gtest/gtest.h>
 
 #ifdef _WIN32
+# include <windows.h>
 # include <crtdbg.h>
 #endif
 
 int main(int argc, char **argv) {
 #ifdef _WIN32
+  // Don't display any error dialogs. This also suppresses message boxes
+  // on assertion failures in MinGW where _set_error_mode/CrtSetReportMode
+  // doesn't help.
+  SetErrorMode(SEM_FAILCRITICALERRORS | SEM_NOGPFAULTERRORBOX |
+    SEM_NOOPENFILEERRORBOX);
   // Disable message boxes on assertion failures.
   _CrtSetReportMode(_CRT_ERROR, _CRTDBG_MODE_FILE | _CRTDBG_MODE_DEBUG);
   _CrtSetReportFile(_CRT_ERROR, _CRTDBG_FILE_STDERR);