diff --git a/appveyor.yml b/appveyor.yml
index b14230a0555f35c4608632cb8c853f30920f9381..0efc9af32cb4e257365245a9fd9fa51708e2fefe 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -17,6 +17,7 @@ install:
   - rustup-init.exe -y --default-host %TARGET%
   - set PATH=%PATH%;C:\Users\appveyor\.cargo\bin
   - if defined MSYS2_BITS set PATH=%PATH%;C:\msys64\mingw%MSYS2_BITS%\bin
+  - if defined MSYS2_BITS for %%I in (crt2.o dllcrt2.o libmsvcrt.a) do xcopy /Y "C:\msys64\mingw%MSYS_BITS%\%ARCH%-w64-mingw32\lib\%%I" "C:\Program Files (x86)\Rust\lib\rustlib\%TARGET%\lib"
   - rustc -V
   - cargo -V
 
diff --git a/libc-test/build.rs b/libc-test/build.rs
index 555aee30c886a5d61518fde05d964134be9a7b25..7006c03b00556592c1a9ddc6b193e01ae42efc87 100644
--- a/libc-test/build.rs
+++ b/libc-test/build.rs
@@ -473,6 +473,11 @@ fn test_windows(target: &str) {
         }
     });
 
+    cfg.skip_roundtrip(move |s| match s {
+        "dirent" | "statfs" | "utsname" | "utmpx" => true,
+        _ => false,
+    });
+
     cfg.generate("../src/lib.rs", "main.rs");
 }
 
@@ -1641,6 +1646,11 @@ fn test_freebsd(target: &str) {
         (struct_ == "sigaction" && field == "sa_sigaction")
     });
 
+    cfg.skip_roundtrip(move |s| match s {
+        "dirent" | "statfs" | "utsname" | "utmpx" => true,
+        _ => false,
+    });
+
     cfg.generate("../src/lib.rs", "main.rs");
 }