There is no longer any reason to use #define USDT1 for the solaris implementation. Solaris 10 supports USDT2.
This is the first step to removing the USDT1 macros altogether (JDK-7102470).
            
This is the first step to removing the USDT1 macros altogether (
- relates to
- 
                    JDK-8034080 Remove the USDT1 dtrace code from Hotspot -           
- Resolved
 
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- 
                    JDK-8032462 Change the linux SDT implementation to use USDT2 instead of USDT1 -           
- Resolved
 
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- 
                    JDK-7102470 RFE: USDT1 versus USDT2 ifdefing should be revisited -           
- Closed
 
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