crt: crt_handler: Skip processing of unwind calls in __mingw_SEH_error_handler

__mingw_SEH_error_handler is processing only exceptions, not unwinds.

Co-authored-by: LIU Hao <lh_mouse@126.com>
Signed-off-by: LIU Hao <lh_mouse@126.com>

mingw-w64-crt/crt/crt_handler.c

diff --git a/mingw-w64-crt/crt/crt_handler.c b/mingw-w64-crt/crt/crt_handler.c
index 636b901..190b900 100644
--- a/mingw-w64-crt/crt/crt_handler.c
+++ b/mingw-w64-crt/crt/crt_handler.c
@@ -85,6 +85,9 @@
   void (*old_handler) (int);
   int reset_fpu = 0;
 
+  if (ExceptionRecord->ExceptionFlags & EXCEPTION_UNWINDING)
+    return ExceptionContinueSearch;
+
   switch (ExceptionRecord->ExceptionCode)
     {
     case EXCEPTION_ACCESS_VIOLATION: