diff --git a/src/library/scala/StringContext.scala b/src/library/scala/StringContext.scala
index b4660590ebc4..43f4a39cb3cc 100644
--- a/src/library/scala/StringContext.scala
+++ b/src/library/scala/StringContext.scala
@@ -389,7 +389,7 @@ object StringContext {
 
   protected[scala] def processUnicode(str: String): String =
     str indexOf "\\" match {
-      case i if i == -1 || i >= (str.length() - 5)  => str
+      case i if i == -1 || i >= (str.length() - 5) => str
       case i => replaceU(str, i)
     }
 
@@ -438,27 +438,28 @@ object StringContext {
       if (next >= 0) {
         //require(str(next) == '\\')
         if (next > i) b.append(str, i, next)
-          var idx = next + 1
-          if (idx >= len) {
-            b.toString()
-          }
-          else {
-            val (ch, advance) = str(idx) match {
-              case 'u'  => readUEscape(str, idx)
-              case chr  => {
-                b.append('\\')
-                (chr, 1)
-              }
+        var idx = next + 1
+        if (idx >= len) {
+          if (idx == len) b.append('\\')
+          b.toString()
+        }
+        else {
+          val (ch, advance) = str(idx) match {
+            case 'u'  => readUEscape(str, idx)
+            case chr  => {
+              b.append('\\')
+              (chr, 1)
             }
-            idx += advance
-            b append ch
-            loop(idx, str.indexOf('\\', idx))
           }
-        } else {
-          if (i < len) b.append(str, i, len)
-          b.toString
+          idx += advance
+          b.append(ch)
+          loop(idx, str.indexOf('\\', idx))
         }
+      } else {
+        if (i < len) b.append(str, i, len)
+        b.toString()
       }
+    }
     loop(0, first)
   }
 
diff --git a/test/files/pos/t11966.scala b/test/files/pos/t11966.scala
new file mode 100644
index 000000000000..2e9632a34869
--- /dev/null
+++ b/test/files/pos/t11966.scala
@@ -0,0 +1,7 @@
+// scalac: -Werror -deprecation
+//
+object Test {
+  val original = """\/ \/ /\"""
+  val minimal = """\1234\"""
+  val alternative = raw"\1234\"
+}
\ No newline at end of file
diff --git a/test/files/run/literals.scala b/test/files/run/literals.scala
index 6e7bae64c677..c569436231f0 100644
--- a/test/files/run/literals.scala
+++ b/test/files/run/literals.scala
@@ -28,11 +28,11 @@ object Test {
     check_success("'\\u005f' == '_'", '\u005f', '_')
 
     //unicode escapes escape in interpolations
-    check_success("bleh", s"\u0024", "$")
-    check_success("bleh", s"""\u0024""", "$")
+    check_success("""s"\\u0024" == "$"""", s"\u0024", "$")
+    check_success("s\"\"\"\\u0024\"\"\" == \"$\"", s"""\u0024""", "$")
 
 
-    //Int#asInstanceOf[Char] gets the char at the codepont
+    //Int#asInstanceOf[Char] gets the char at the codepoint
     check_success("65.asInstanceOf[Char] == 'A'", 65.asInstanceOf[Char], 'A')
     
     // boolean