How do upgrade GWT in Eclipse

How do upgrade GWT in Eclipse

• Download the GWT SDK(s) you need from https://developers.google.com/web-toolkit/versions
• Extract it anywhere you like
• In Eclipse Preferences > Google > Web Toolkit, use the "Add..." button and navigate to the GWT SDK directory
• Then, in each Eclipse project's properties page (Project > Properties > Google > Web Toolkit), you can choose one of your installed SDKs.  

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Eclipse (ADT) crash Failed to write core dump. Core dumps have been disabled

I found my problem here: how to fix “Failed to write core dump. Core dumps have been disabled” error while running java and here: Eclipse crashing on startup and here: Eclipse continue crash