As I hinted in my original bug report, the MapServer community has
long maintained that the PHP/MapScript extension is most stable when
PHP is configured to run in CGI mode. I have a link to the MapServer
Wiki that very clearly corroborates this. See here:
The relevant quote from the Wiki is as follows:
Due to some thread-safety problems (and some heritage from PHP3 in the
php_mapscript.c code), PHPMapScript versions 3.5 (and 3.6-dev at
least) will produce intermittent errors and crashes when used under
PHP configured as an Apache DSO or as an ISAPI module.
The workaround (until we rework the PHPMapScript code) is to configure
your PHP as a CGI and then things will work just fine.
As far as I know, and I have been following the mapserver-users
mailing list for a few years now, the above-quoted advice still
applies to the current version of MapServer (5.0.0, as I write this).
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