Need reviewer - jdk7u-osx Mac sanity check fixes

[Mike Swingler]

On Dec 20, 2011, at 8:43 AM, Kelly O'Hair wrote:

> On Dec 19, 2011, at 11:39 PM, Alex Strange wrote:
> 
>>> If you are restricting your builders to Mac OS X 10.7 now, you can actually cut over to using clang soon, since it has no known bugs compiling the JDK (right Alex? I'm not completely hallucinating this right?)
>>> 
>>> Regards,
>>> Mike Swingler
>>> Apple Inc.
>> Clang works fine to compile jdk. However, the build for hotspot is very unclean and prints thousands of warnings, because clang enables more warnings by default than gcc. I resorted to building with "clang -w" as printing all the warnings actually resulted in a slower compile time than using llvm-gcc.
>> 
>> Cleaning the build up will take some work, but you should look into it as Clang is a much faster compiler and uses a newer version of the compiler backend.
> 
> Please don't fall into the trap of 'it compiles fine'. I'm all for using the latest and greatest compilers,
> but when it comes to building something like hotspot, just be very very careful.
> The fact that clang uses a newer compiler backend make me even more nervous for hotspot and everyone's
> code generation playing well together at runtime.

Of course, it needs to be tested - but Apple has a demonstrated history of not letting any legacy technologies live on for long, and I want to ensure that JDK8 is on a supported compiler when it comes time to ship. Changing compilers mid-product cycle is never fun.

Regards,
Mike Swingler
Apple Inc.