--- origsrc/compiler-rt-8.0.1.src/cmake/config-ix.cmake	2019-08-27 21:25:49.733158500 -0400
+++ src/compiler-rt-8.0.1.src/cmake/config-ix.cmake	2019-08-27 21:59:59.356608500 -0400
@@ -37,6 +37,18 @@ if (COMPILER_RT_HAS_NODEFAULTLIBS_FLAG)
   elseif (COMPILER_RT_HAS_GCC_LIB)
     list(APPEND CMAKE_REQUIRED_LIBRARIES gcc)
   endif ()
+  if (CYGWIN)
+    # Cygwin requires quite a few "C" runtime libraries in order for basic
+    # programs to link successfully with -nodefaultlibs.
+    if (COMPILER_RT_USE_BUILTINS_LIBRARY)
+      set(CYGWIN_RUNTIME ${COMPILER_RT_BUILTINS_LIBRARY})
+    else ()
+      set(CYGWIN_RUNTIME gcc_s gcc)
+    endif()
+    set(CYGWIN_LIBRARIES ${MINGW_RUNTIME} cygwin advapi32
+                        shell32 user32 kernel32 ${CYGWIN_RUNTIME})
+    list(APPEND CMAKE_REQUIRED_LIBRARIES ${CYGWIN_LIBRARIES})
+  endif()
   if (MINGW)
     # Mingw64 requires quite a few "C" runtime libraries in order for basic
     # programs to link successfully with -nodefaultlibs.