[libcxx] [test] Add a specific XFAIL for a MinGW env failure that is fixed in Clang 14

This issue only occurs when linked statically in MinGW configurations,
and has been fixed for Clang 14 by https://reviews.llvm.org/D109651.

Differential Revision: https://reviews.llvm.org/D112214

Author: mstorsjo

libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/F.pass.cpp

@@ -16,6 +16,12 @@
 
 // UNSUPPORTED: sanitizer-new-delete
 
+// This fails on MinGW when statically linked, if built with Clang 13 or older.
+// (It's fixed in the upcoming Clang 14, by https://reviews.llvm.org/D109651.)
+// Prior to the fix, when statically linked, the unwind info for the two
+// (default and overridden) operator new implementations clash.
+// XFAIL: target={{.+}}-windows-gnu && !windows-dll && clang-13
+
 #include <thread>
 #include <new>
 #include <atomic>