Hi all, We recently had an error in production which was hard to reproduce, hard to debug, and turned out to be a bug in an extension. One of the oddest symptoms was that the PHP code seemed to run to completion, but the request was never logged by Apache.
The only thing logged was the words "zend_mm_heap corrupted", in the Apache error log. As far as I can see, this ultimately comes from zend_mm_panic [1], which (on non-Windows non-debug builds) is simply: fprintf(stderr, "%s\n", message); exit(1); Frustratingly, this error: - Doesn't contain a timestamp - Doesn't contain any context of where the error happened (not even a hint that this happened during shutdown rather than execution) - Doesn't mention PHP, or look like the messages PHP would normally log - Doesn't log to the PHP error log - Doesn't register as an error in Apache itself The server in question was running PHP as an Apache module in pre-fork mode; in that configuration, stderr gets slurped into the Apache error log without annotation, and the exit(1) silently terminates the connection and logs nothing. I suspect this is one of those last-ditch errors where there is a risk of causing further errors if global data is accessed, but is there any way this message can be improved, at least to format it more like other PHP errors? [1] https://github.com/php/php-src/blob/1154f6f70a3e4ee083f1bc42d83c190ad68f3862/Zend/zend_alloc.c#L348 Regards, -- Rowan Collins [IMSoP]
