Update README for Eclipse setup

1 files changed, 10 insertions, 3 deletions

diff --git a/src/eclipse/README.md b/src/eclipse/README.md
index 03c7403b04..a0152faa86 100644
--- a/src/eclipse/README.md
+++ b/src/eclipse/README.md
@@ -6,8 +6,8 @@ The following points describe how to get Scala to run in Eclipse. Please also ta
 0. Import all projects into a [very recent version of Scala IDE for Eclipse](http://scala-ide.org/download/nightly.html) by choosing `File/Import Existing Projects`
 and navigate to `scala/src/eclipse`. Check all projects and click ok.
 
-0. You need to define a `path variable` inside Eclipse. Define `SCALA_BASEDIR` in 
-`Preferences/General/Workspace/Linked Resources`. The value should be the absolute 
+0. You need to define a `path variable` inside Eclipse. Define `SCALA_BASEDIR` in
+`Preferences/General/Workspace/Linked Resources`. The value should be the absolute
 path to your Scala checkout. All paths in the project files are relative to this one,
 so nothing will work before you do so.
 
@@ -29,7 +29,7 @@ JDK. The Scala library uses such APIs, so you'd see this error:
         Access restriction: The method compareAndSwapObject(Object, long, Object, Object)
         from the type Unsafe is not accessible due to restriction on required library.
 
-  You can *fix* it by allowing calls to restricted APIs in `Java/Compiler/Errors/Warnings/Deprecated and Restricted API` 
+  You can *fix* it by allowing calls to restricted APIs in `Java/Compiler/Errors/Warnings/Deprecated and Restricted API`
 settings.
 
 0. Project files are tracked by Git, so adding them to `.gitignore` won't prevent them
@@ -42,6 +42,13 @@ consider them unchanged:
 
         git update-index --no-assume-unchanged `find src/eclipse -iname .classpath -or -iname .project`
 
+0. The 2.12, sources of Scala need to be built with a 2.12 version of the compiler. One can configure a 2.12 Scala installation
+in Eclipse. In order to do this, go to `Window -> Preferences -> Scala -> Installations` and add a 2.12 installation. You can
+either download a prepackaged version of 2.12 from the Scala homepage or you add the Scala installation that is part of the
+`build/pack/lib` directory. The latter is required in case you absolutely need to depend on a nightly build of the compiler to
+compile the compiler itself. Once the 2.12 Scala installation is created you need to select all Scala projects, do a right click
+and select `Scala -> Set the Scala installation` where you have to choose the newly created 2.12 Scala installation.
+
 If it doesn’t compile
 =====================