diff --git a/lib/nimbase.h b/lib/nimbase.h
index 40ea6c66a..266b84b09 100644
--- a/lib/nimbase.h
+++ b/lib/nimbase.h
@@ -91,10 +91,25 @@ __clang__
 #  define NIM_CONST  const
 #endif
 
-#if (defined(WIN32) || defined(_WIN32) || defined(__WIN32__))
-#  define NIM_THREADVAR __declspec(thread)
-#else
+/*
+  NIM_THREADVAR declaration based on
+  http://stackoverflow.com/questions/18298280/how-to-declare-a-variable-as-thread-local-portably
+*/
+#if __STDC_VERSION__ >= 201112 && !defined __STDC_NO_THREADS__
+#  define NIM_THREADVAR _Thread_local
+#elif defined _WIN32 && ( \
+       defined _MSC_VER || \
+       defined __ICL || \
+       defined __DMC__ || \
+       defined __BORLANDC__ )
+#  define NIM_THREADVAR __declspec(thread) 
+/* note that ICC (linux) and Clang are covered by __GNUC__ */
+#elif defined __GNUC__ || \
+       defined __SUNPRO_C || \
+       defined __xlC__
 #  define NIM_THREADVAR __thread
+#else
+#  error "Cannot define NIM_THREADVAR"
 #endif
 
 /* --------------- how int64 constants should be declared: ----------- */
diff --git a/lib/pure/collections/sets.nim b/lib/pure/collections/sets.nim
index aa4919884..20f73ded3 100644
--- a/lib/pure/collections/sets.nim
+++ b/lib/pure/collections/sets.nim
@@ -18,7 +18,7 @@
 ## that ``=`` performs a copy of the set.
 
 import
-  os, hashes, math
+  hashes, math
 
 {.pragma: myShallow.}
 when not defined(nimhygiene):
diff --git a/lib/pure/uri.nim b/lib/pure/uri.nim
index abb1a462d..f0a3796a5 100644
--- a/lib/pure/uri.nim
+++ b/lib/pure/uri.nim
@@ -255,13 +255,13 @@ proc `/`*(x: Uri, path: string): Uri =
   ## Examples:
   ##
   ## .. code-block::
-  ##   let foo = parseUri("http://example.com/foo/bar") / parseUri("/baz")
+  ##   let foo = parseUri("http://example.com/foo/bar") / "/baz"
   ##   assert foo.path == "/foo/bar/baz"
   ##
-  ##   let bar = parseUri("http://example.com/foo/bar") / parseUri("baz")
+  ##   let bar = parseUri("http://example.com/foo/bar") / "baz"
   ##   assert bar.path == "/foo/bar/baz"
   ##
-  ##   let bar = parseUri("http://example.com/foo/bar/") / parseUri("baz")
+  ##   let bar = parseUri("http://example.com/foo/bar/") / "baz"
   ##   assert bar.path == "/foo/bar/baz"
   result = x
   if result.path[result.path.len-1] == '/':