Compile error with Xcode 6.3.1

[Christian Thalinger]

This is a known issue and was fixed in 9:

https://bugs.openjdk.java.net/browse/JDK-8077364 <https://bugs.openjdk.java.net/browse/JDK-8077364>

Graal people use the COMPILER_WARNINGS_FATAL variable to ignore these.

> On Apr 24, 2015, at 10:28 AM, Renze Torensma <renzetorensma at gmail.com> wrote:
> 
> I tried compiling Graal today with the jdk1.8.0_45 on OSX 10.10.3 with Xcode 6.3.1 installed, and got some compiler errors:
> 
> */filebuff.cpp:109:8: error: 'this' pointer cannot be null in well-defined C++ code; pointer may be assumed to always convert to true [-Werror,-Wundefined-bool-conversion]
> 
>  if( !this ) return NULL;      // The empty buffer region
> 
>      ~^~~~
> 
> */filebuff.cpp:122:8: error: 'this' pointer cannot be null in well-defined C++ code; pointer may be assumed to always convert to true [-Werror,-Wundefined-bool-conversion]
> 
>  if( !this ) return br;        // Merging into nothing
> 
>      ~^~~~
> 
> */filebuff.cpp:244:8: error: 'this' pointer cannot be null in well-defined C++ code; pointer may be assumed to always convert to true [-Werror,-Wundefined-bool-conversion]
> 
>  if( !this ) return;           // Nothing to print
> 
>      ~^~~~
> 
> 3 errors generated.
> 
> */formssel.cpp:3393:8: error: 'this' pointer cannot be null in well-defined C++ code; pointer may be assumed to always convert to true [-Werror,-Wundefined-bool-conversion]
> 
>  if( !this ) return;
> 
>      ~^~~~
> 
> 1 error generated.
> 
> It seems like this error is introduced by clang 6.1 which is bundled with Xcode 6.3: https://bugs.openjdk.java.net/browse/JDK-8077364?page=com.atlassian.streams.streams-jira-plugin:activity-stream-issue-tab