Update README.md

bin/README.md

@@ -0,0 +1,30 @@
+# The Odin Programming Language
+
+## Setup
+
+Odin only supports x86-64 at the moment (64-bit), relies on LLVM for code generation and an external linker.
+
+In addition, the following platform-specific steps are necessary:
+
+- Windows
+    * Have Visual Studio installed (MSVC 2010 or later, for the linker)
+    * Have a copy of `opt.exe` and `llc.exe` in `Odin/bin`. Pre-built Windows binaries can be found [here](https://github.com/odin-lang/Odin/releases/tag/llvm-windows) and *must* be explicitly copied
+    * Open a valid command prompt:
+        * **Basic:** run the `x64 Native Tools Command Prompt for VS2017` shortcut bundled with VS 2017, or
+        * **Advanced:** run `vcvarsall.bat x64` from a blank `cmd` session
+
+- MacOS
+    * Have LLVM explicitly installed (`brew install llvm`)
+    * Have XCode installed (version X.X or later, for linking)
+    * Make sure the LLVM binaries and the linker are added to your `$PATH` environmental variable
+
+- GNU/Linux
+    * Have LLVM installed (opt/llc)
+    * Have Clang installed (version X.X or later, for linking)
+    * Make sure the LLVM binaries and the linker are added to your `$PATH` environmental variable
+
+Then build the compiler by calling `build.bat` (Windows) or `make` (Linux/MacOS). This will automatically run the demo program if successful.
+
+**Notes for Linux:**: The compiler currently relies on the `core` and `shared` library collection being relative to the compiler executable. Installing the compiler in the usual sense (to `/usr/local/bin` or similar) is therefore not as straight forward as you need to make sure the mentioned libraries are available. As a result, it is recommended to simply explicitly invoke the compiler with `/path/to/odin` in your preferred build system, or add `/path/to/odin` to `$PATH`.
+
+Please read the [Getting Started Guide](https://github.com/odin-lang/Odin/wiki#getting-started-with-odin) for more information.