Merge pull request #307 from dissimiral/master

Fix docs

Author: gribozavr

docs/DebuggingTheCompiler.rst

@@ -37,7 +37,7 @@ Here is how to dump the IR after the main phases of the swift compiler
 #. **Performance SIL passes**. To print the SIL after the complete SIL
    optimization pipeline::
 
-    swiftc -emit-sil -O file-swift
+    swiftc -emit-sil -O file.swift
 
 #. **IRGen**. To print the LLVM IR after IR generation::