centos gcc编译 mysql 问题发现

一点点来：

编译不通过非常郁闷

20.7.16.1. Problems Linking to the MySQL Client Library

When linking with the C API, the following errors may occur on some systems:

gcc -g -o client test.o -L/usr/local/lib/mysql \                        -lmysqlclient -lsocket -lnslUndefined        first referenced symbol          in filefloor            /usr/local/lib/mysql/libmysqlclient.a(password.o)ld: fatal: Symbol referencing errors. No output written to client

If this happens on your system, you must include the math library by adding -lm to the end of the compile/link line.

Linking with the single-threaded library (libmysqlclient) may lead to linker errors related topthread symbols. When using the single-threaded library, please compile your client withMYSQL_CLIENT_NO_THREADS defined. This can be done on the command line by using the-D option to the compiler, or in your source code before including the MySQL header files. This define should not be used when building for use with the thread-safe client library (libmysqlclient_r).

When you are linking an application program to use the MySQL client library, you might get undefined reference errors for symbols that start withmysql_, such as those shown here:

/tmp/ccFKsdPa.o: In function `main':/tmp/ccFKsdPa.o(.text+0xb): undefined reference to `mysql_init'/tmp/ccFKsdPa.o(.text+0x31): undefined reference to `mysql_real_connect'/tmp/ccFKsdPa.o(.text+0x57): undefined reference to `mysql_real_connect'/tmp/ccFKsdPa.o(.text+0x69): undefined reference to `mysql_error'/tmp/ccFKsdPa.o(.text+0x9a): undefined reference to `mysql_close'

You should be able to solve this problem by adding -Ldir_path -lmysqlclientat the end of your link command, where dir_path represents the path name of the directory where the client library is located. To determine the correct directory, try this command:

shell> mysql_config --libs

The output from mysql_config might indicate other libraries that should be specified on the link command as well.

If you get undefined reference errors for the uncompress or compress function, add -lz to the end of your link command and try again.

If you get undefined reference errors for a function that should exist on your system, such asconnect, check the manual page for the function in question to determine which libraries you should add to the link command.

You might get undefined reference errors such as the following for functions that don't exist on your system:

mf_format.o(.text+0x201): undefined reference to `__lxstat'

This usually means that your MySQL client library was compiled on a system that is not 100% compatible with yours. In this case, you should download the latest MySQL source distribution and compile MySQL yourself. SeeSection 2.17, “Installing MySQL from Source”.

You might get undefined reference errors at runtime when you try to execute a MySQL program. If these errors specify symbols that start withmysql_ or indicate that the mysqlclient library can't be found, it means that your system can't find the sharedlibmysqlclient.so library. The fix for this is to tell your system to search for shared libraries where the library is located. Use whichever of the following methods is appropriate for your system:

• Add the path to the directory where libmysqlclient.so is located to theLD_LIBRARY_PATH environment variable.

• Add the path to the directory where libmysqlclient.so is located to theLD_LIBRARY environment variable.

• Copy libmysqlclient.so to some directory that is searched by your system, such as/lib, and update the shared library information by executingldconfig.

Another way to solve this problem is by linking your program statically with the-static option, or by removing the dynamic MySQL libraries before linking your code. Before trying the second method, you should be sure that no other programs are using the dynamic libraries.

我的问题是在红色和紫色那两个地方搞定到，我装到是64位到linux ，新人看两一点make就去搞这个玩意直接悲剧了……还好mysql官网有类似的到问题

 

部分转自：http://dev.mysql.com/doc/refman/5.0/en/c-api-linking-problems.html