mysql_config --libs gives incorrect output on Centos7

[Roel Van de Paar]

$ mysql_config --libs
-L/usr/lib64 -lmysqlclient -lpthread -lm -lrt -lssl -lcrypto -ldl

But, when you try and compile some C program using `mysql_config --libs` as part of the gcc call, it fails. Reason (after much digging) is that the output above is wrong, it should instead read:

-L/usr/lib64/mysql -lmysqlclient -lpthread -lm -lrt -lssl -lcrypto -ldl

As this is where the client libs are;

$ ls /usr/lib64/mysql
libmysqlclient.a libmysqlclient_r.a libmysqlservices.a

Not sure how widespread this is in other Centos releaes etc.

This makes compiling programs with Percona Server client statically linked very difficult (it took Sergei & me about 1+ hours to work it out together), so this bug is high prio to aid client adoption.

Workaround is to do something like `mysql_config --libs | sed 's|lib64|lib64/mysql|'` instead.

Setup for testing;
sudo yum install http://www.percona.com/downloads/percona-release/redhat/0.1-3/percona-release-0.1-3.noarch.rpm
sudo yum install Percona-Server-devel-56 Percona-Server-client-56 Percona-Server-shared-56

Background:
https://dev.mysql.com/doc/refman/5.6/en/c-api-building-clients.html

[Roel Van de Paar (roel11)]

Previous releases of Centos should also be checked for the libperconaserverlcient implementation. In that case, the above may still apply (re: additional subdir), but additionally also the -lmysqlclient output of mysql_config should represent the correct client lib instead.

[Roel Van de Paar (roel11)]

If the -l client lib is indeed incorrect, it is one more reason to revert to standard client lib name imho.

[Roel Van de Paar (roel11)]

For upstream, the files are also in lib64/mysql. Yet, -lmysqlclient works fine without problems there.

[Roel Van de Paar (roel11)]

Mariadb otoh fixes the same with using subdir.

$ mysql_config --libs
-L/usr/lib64/mysql -lmysqlclient -lpthread -lz -lm -lssl -lcrypto -ldl