Merge pull request rust-lang#4271 from tgross35/fix-cherry-pick

[0.2] Re-add the test for `primitive_types`

Author: tgross35

libc-test/Cargo.toml

@@ -88,3 +88,8 @@ harness = true
 name = "semver"
 path = "test/semver.rs"
 harness = false
+
+[[test]]
+name = "primitive_types"
+path = "test/primitive_types.rs"
+harness = true