RFR: 8080775: Better argument formatting for assert() and friends (original) (raw)

David Lindholm david.lindholm at oracle.com
Tue Sep 22 11:38:52 UTC 2015

Hi,

Please review the following patch which removes the need to use err_msg() or err_msg_res() to format strings that are sent to assert(), guarantee(), fatal() and vm_exit_out_of_memory(). These are now variadic macros. So,

guarantee(_saved_index == _index, err_msg("saved index: %d index: %d", _saved_index, _index));

is replaced by

guarantee(_saved_index == _index, "saved index: %d index: %d", _saved_index, _index);

This change also eliminates the need to choose if the buffer for the formatted string should be allocated on the stack (with err_msg()) or in the resource area (with err_msg_res()). There is no longer any need to allocate this extra buffer, since the va_list is sent all the way down to the functions writing the error to screen or file.

To accommodate for this, VMError is now AllStatic. All patterns of usages of this class was to create a VMError and immediately call report_and_die() on it.

Now, instead of having multiple constructors, there are multiple static VMError::report_and_die().

I have also removed all usages of err_msg() and err_msg_res() in assert(), guarantee(), fatal() and vm_exit_out_of_memory() in this patch. err_msg_res() is completely removed, err_msg() is still used by other functions.

Since we have about 1000 asserts with "" as detailed message, I had to disable the gcc-only warning for empty format strings.

(As a side note, there is also a JBS bug that describes a name change from assert to vmassert in our code. This changeset does not include such a name change, since we have over 19000 asserts in our code. We still have a "#define assert vmassert" just like before).

Bug: https://bugs.openjdk.java.net/browse/JDK-8080775 Webrev: http://cr.openjdk.java.net/~david/JDK-8080775/webrev.00/

Testing: Passed JPRT

Thanks, David

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