RFR (S): 8211394: CHECK_ must be used in the rhs of an assignment statement within a block (original) (raw)

David Holmes david.holmes at oracle.com
Sun Oct 7 22:08:34 UTC 2018


Bug: https://bugs.openjdk.java.net/browse/JDK-8211394 webrev: http://cr.openjdk.java.net/~dholmes/8211394/webrev/

If a CHECK_ macro is used on a function call that is part of a return statement i.e.

return foo(CHECK_NULL);

then it expands into an unreachable if-statement that checks the exception state:

return foo(); if (EXCEPTION_OCCURRED) return NULL;

This is obviously a programming error, but unfortunately not something our often pedantic compilers complain about.

There are two ways to fix:

  1. Convert to assignment:

T* t = foo(CHECK_NULL); return t;

  1. If the method is local and its exception behaviour easily discernible and matches the expected behaviour, then change CHECK_ to THREAD

return foo(THREAD);

Both fixes are applied as appropriate. As per the bug report I also revisited an earlier fix in this area - JDK-8062808 - and made adjustments.

Thanks, David



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