[PATCH] Add section about clang-cl to UsersManual.rst

[Reid Kleckner]

================
Comment at: docs/UsersManual.rst:48
@@ -47,1 +47,3 @@
+Clang also provides an alternative driver, :ref:`clang-cl`, that is designed
+to be compatible with Visual Studio's compiler.
 
----------------
"the Visual C++ compiler, cl.exe"?

I always get the terminology wrong in conversation, but I think for the docs we should probably refer mostly to Visual C++ instead of Visual Studio, which most people consider to refer to the IDE.  There are more instances below.

================
Comment at: docs/UsersManual.rst:1441-1442
@@ +1440,4 @@
+
+Options that are not known to clang-cl will cause errors. If they are spelled with a
+leading ``/``, they will be mistaken for a filename:
+
----------------
Maybe we should fix that.  I think I needed this hack in LLVMOption to avoid breaking things on Linux, since '/' is in the set of option prefixes, even though no flag with a / prefix is recognized in the normal clang driver.

================
Comment at: docs/UsersManual.rst:1414
@@ +1413,3 @@
+
+clang-cl is an alternative Clang driver, designed for compatibility with
+Visual Studio's compiler, cl.exe.
----------------
Most people reasonably expect that "driver" means "kernel device driver", and not "helper to drive compilation".  Maybe "is an alternative command line interface for clang"?  I think any further use of the word driver will be obvious from context.


http://llvm-reviews.chandlerc.com/D1881