diff --git a/patches/bdwgc_pre.local.patch b/patches/bdwgc_pre.local.patch
index dfb7f7a..2021312 100644
--- a/patches/bdwgc_pre.local.patch
+++ b/patches/bdwgc_pre.local.patch
@@ -20,12 +20,3 @@
        *-*-mingw*)
          AC_DEFINE(GC_WIN32_PTHREADS)
          # Using pthreads-win32 (or other non-Cygwin pthreads) library.
-@@ -810,7 +814,7 @@
-        [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([
- #         ifdef __CYGWIN__
- #           define _GNU_SOURCE 1
--#         elif defined(__linux__) || defined(__GLIBC__) || defined(__GNU__)
-+#         elif defined(__linux__) || defined(__GLIBC__) || defined(__GNU__) || defined(__midipix__)
- #           define _GNU_SOURCE 1
- #         endif
- #         include <pthread.h>