RFR: 8216385: ZGC: Fix building without C2

[Per Liden]

On 01/08/2019 09:43 PM, Aleksey Shipilev wrote:
> On 1/8/19 9:40 PM, Aleksey Shipilev wrote:
>> Just built it with "--with-debug-level=fastdebug --disable-precompiled-headers
>> --with-jvm-features=-compiler2", and it breaks:
>>
>> /home/shade/jdk-jdk/src/hotspot/os_cpu/linux_x86/gc/z/zArguments_linux_x86.cpp:31:5: error:
>> "COMPILER2" is not defined [-Werror=undef]
>>   #if COMPILER2
>>       ^~~~~~~~~
>>
>> It should be #ifdef, not #if...
> 
> ...and no need for additional #include, it seems to get there through build flags, not through
> utilities/macros.hpp.

Doh! You're right of course.

http://cr.openjdk.java.net/~pliden/8216385/webrev.1

/Per

> 
> -Aleksey
>