BSD variables not declared? (jdk8 & jdk 9 builds)

[David Holmes]

On 14/04/2015 5:24 PM, Magnus Ihse Bursie wrote:
> On 2015-04-12 17:01, Martijn Verburg wrote:
>> Hi all,
>>
>> On Mac OS X 10.10.2 using gcc 4.8 run make clean images
>>
>> When compiling either jdk8 or jdk9 from scratch I get the following BSD
>> undefined errors:
>>
>> Compiling
>> /Users/karianna/Documents/workspace/AdoptOpenJDK_projects/jdk8/hotspot/src/os/bsd/vm/os_bsd.cpp
>>
>> /Users/karianna/Documents/workspace/AdoptOpenJDK_projects/jdk8/hotspot/src/os/bsd/vm/os_bsd.cpp:1150:7:
>>
>> error: "__FreeBSD__" is not defined [-Werror=undef]
>>   #elif __FreeBSD__
>>         ^
>> /Users/karianna/Documents/workspace/AdoptOpenJDK_projects/jdk8/hotspot/src/os/bsd/vm/os_bsd.cpp:1152:7:
>>
>> error: "__OpenBSD__" is not defined [-Werror=undef]
>>   #elif __OpenBSD__
>>         ^
>> /Users/karianna/Documents/workspace/AdoptOpenJDK_projects/jdk8/hotspot/src/os/bsd/vm/os_bsd.cpp:1154:7:
>>
>> error: "__NetBSD__" is not defined [-Werror=undef]
>>   #elif __NetBSD__
>
> That sounds strange. Why would an undefined preprocessor variable
> trigger an error? I have never heard about this before.

"-Wundef option causes GCC to warn whenever it encounters an identifier 
which is not a macro in an ‘#if’. "

Hence we should be using

#elif defined(__FreeBSD__)

etc in this context. It may be the compiler normally doesn't look at the 
erroneous else cases, but this compiler does (or else __APPLE__ is not 
defined and so we hit these else cases where we don't normally.) ??

> Since it is in hotspot code, maybe you can get a better response by
> asking on a hotspot list.

Yes looks like a hotspot issue. I filed:

https://bugs.openjdk.java.net/browse/JDK-8077674

Follow ups on hotspot-runtime-dev please.

David

> /Magnus