The problem was manifestated only with BIT columns and only when more than
one row was fetched. The problem was coming from the fact that in pre-7.0
times mysqlnd was using a no-copy optimization. This optimization kept the
strings (and also the BIT mask equivalents as strings) in the packet and the
zval referred to them. 7.0+ zvals cannot use no-copy and always copy. Because
of this the allocated memory for the packet was reduced by 1 by the person who
ported the driver, but the starting address of the bit area wasn't reduced.
Because of this the bit_area started at wrong address and the length decoded
wrong.
If this does not break the Unix system somehow, I'll be amazed. This should get most of it out, apologies for any errors this may cause on non-Windows ends which I cannot test atm.
MYSQL_OPT_READ_TIMEOUT was never a macro in mysqlnd but an enum value.
So this never actually worked correctly. mysqlnd provides these so it is
safe to have them when mysqlnd used.
The reason was that after the big refactoring of mysqlnd at the end of
last year code that is initializing the error_info structure in the
result set was not added. It existed already for connections and PS.
The code that segfaults is hit only with MariaDB because MariaDB sends
full metadata about the EXPLAIN query + EOF packet and only then it sends
an error packet. MySQL doesn't do that but sends directly an error which
is caught (by different code path). As errors during execution (which means
after sending meta) are pretty rare there was no test case of MySQL to
catch it.
These are either in debug code (fix them), commented out (drop
them) or in dead compatibility macros (drop them).
One usage was in php_stream_get_from_zval(), which we have not used
since at least PHP 5.2 and, judging from the fact that nobody
complained about it causing compile errors in PHP 7, nobody else
uses it either, so drop it.
There are still remaining uses in mysqli embedded and odbc birdstep.
These probably need to be dropped outright.
PHP_VERSION_ID
PHP_API_VERSION
ZEND_MODULE_API_NO
PHP_MAJOR_VERSION, PHP_MINOR_VERSION
ZEND_ENGINE_2
I've left litespeed alone, as it seems to genuinely maintain support
for many PHP versions.
