Linker Issue

james_b · 12-19-2011, 04:47 PM

Hiya,

I'm trying to build the MySQL Connector/C++ on Oracle Linux and gcc.

Code:

$ g++ --version
g++ (GCC) 4.4.5 20110214 (Red Hat 4.4.5-6)

$ cmake .
(snip)
-- MySQL Library dir: /usr/lib64
(snip)

$ make clean
$ make
(snip...)
/usr/bin/ld: cannot find -lmysqlclient_r
collect2: ld returned 1 exit status

I'm fairly new to cmake and gcc, but this seems to be saying it can't find the libmysqlclient_r library.

I can verify that libmysqlclient_r.a is in /usr/lib64/mysql, not /usr/lib64/. Is there anyway I can pass this directory to cmake and/or ld so that it finds the library?

Any suggestions are much appreciated!

Cheers

dwhitney67 · 12-20-2011, 10:07 AM

Try something like:

Code:

LDFLAGS=-L/usr/lib64/mysql make

If this does not work, then take a peek at the Makefile to see what variable is used to store the -L/usr/lib64 path. Then check to see if it is assigned using a "+=" (versus a mere "="). If the variable name is different from LDFLAGS, then substitute the proper name within the command above.

You may also want to read the following (which I was able to Google): http://www.vtk.org/Wiki/CMake:How_To_Find_Libraries

hj1967 · 12-20-2011, 10:10 AM

Quote:

Originally Posted by james_b

Hiya,

I'm trying to build the MySQL Connector/C++ on Oracle Linux and gcc.

Code:

$ g++ --version
g++ (GCC) 4.4.5 20110214 (Red Hat 4.4.5-6)

$ cmake .
(snip)
-- MySQL Library dir: /usr/lib64
(snip)

$ make clean
$ make
(snip...)
/usr/bin/ld: cannot find -lmysqlclient_r
collect2: ld returned 1 exit status

I'm fairly new to cmake and gcc, but this seems to be saying it can't find the libmysqlclient_r library.

I can verify that libmysqlclient_r.a is in /usr/lib64/mysql, not /usr/lib64/. Is there anyway I can pass this directory to cmake and/or ld so that it finds the library?

Any suggestions are much appreciated!

Cheers

You can use the -L/<path> option to tell the linker to look in other directies.
The commandline will look like:

g_+ -o myprog myprog.o -L/usr/lib64/mysql -lmysqlclient

I don't know cmake but it should be possible to use specify the -Lpath in the cmake file.