Re: BUG #12275: configure incorrectly tests libxml2 version

Alvaro Herrera <alvherre@2ndquadrant.com> writes:
> greg.davidson@gmail.com wrote:
>> I had to comment out the libxml2 version check to get 9.4.0 to build.
>> Perhaps it's because of the suffix on the version number?
>> $ ./configure --with-libxml --with-libxslt --enable-debug --enable-cassert
>> \
>> --with-tcl --with-tclconfig=/usr/lib/tcl8.6 --prefix=/usr/local/pgsql-9.4.0
>> ...
>> checking for xmlSaveToBuffer in -lxml2... no
>> configure: error: library 'xml2' (version >= 2.6.23) is required for XML
>> support

> I have 2.9.1 Debian-packaged here, and it works fine for me.  config.log
> says:

> configure:8767: checking for xmlSaveToBuffer in -lxml2
> configure:8801: result: yes

There is no version check as such in the test; it's just looking to see if
xmlSaveToBuffer() links successfully.  The complaint message is worded
like that because xmlSaveToBuffer() didn't exist before 2.6.23.

> I don't have the :i386 packages installed here; maybe your compiler is
> picking up those instead of the amd64 ones.

That or some other link failure seems like the probable cause.  Looking
into config.log to see what error messages the underlying tools printed
would probably be helpful.

            regards, tom lane