Question

由于某些未知原因，我的libmysqlclient.a在我的CentOS 7中消失了。然后我的程序出现了链接器错误，说无法找到libmysqlclient。

然后我发现我的mysql-devel包已经消失了：

yum info mysql-devel
yum install mysql-devel

以下是回复：

Loaded plugins: fastestmirror
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 * updates: repo.virtualhosting.hk
Package MariaDB-devel-10.2.5-1.el7.centos.x86_64 already installed and latest version

所以我想也许我应该使用libmariadbclient，但是当我用libmariadbclient链接我的程序时，它有链接错误：

/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x191): undefined reference to `CRYPTO_num_locks'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1aa): undefined reference to `CRYPTO_THREADID_set_callback'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1b6): undefined reference to `CRYPTO_set_locking_callback'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1bb): undefined reference to `SSL_library_init'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1c7): undefined reference to `SSL_load_error_strings'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1cc): undefined reference to `OPENSSL_add_all_algorithms_noconf'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x2b4): undefined reference to `CRYPTO_set_locking_callback'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x2bb): undefined reference to `CRYPTO_set_id_callback'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x2df): undefined reference to `CRYPTO_num_locks'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x340): undefined reference to `EVP_cleanup'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x345): undefined reference to `CRYPTO_cleanup_all_ex_data'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x34a): undefined reference to `ERR_free_strings'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x351): undefined reference to `CONF_modules_free'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_init':
(.text+0x3e1): undefined reference to `SSLv23_client_method'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `my_cb_threadid':
(.text+0x1e): undefined reference to `CRYPTO_THREADID_set_numeric'
/usr/lib64//libmariadbclient.a(ma_compress.c.o): In function `_mariadb_compress_alloc':
(.text+0x5d): undefined reference to `compress'
/usr/lib64//libmariadbclient.a(ma_compress.c.o): In function `_mariadb_uncompress':
(.text+0x191): undefined reference to `uncompress'
collect2: error: ld returned 1 exit status

我一直在使用libmysqlclient连接我的MariaDB 10.1，并且最近一直在尝试从源代码构建它，但由于OpenSSL 1.1版本的问题而失败了。在这里你看到我的另一篇文章：

Error "incomplete type MD5_CONTEXT" with MariaDB 10.2 and Openssl 1.1.0e

所以我很困惑为什么mysqlclient.a消失了，我应该使用哪个lib。

有人可以帮忙吗？

谢谢！

Answer 1

尝试使用＆＃34; -lmariadbclient ＆＃34;编译我的程序时遇到了类似的问题。（在apt-get update -lmysqlclient 停止工作之后）。我使用的Makefile是：

g++ -std=c++11 *.cpp ../common/*.cpp ../common/*.c -o myprogram -I.. -ldl -Wstack-protector -fstack-protector-all -pthread -ggdb -lmariadbclient -Wwrite-strings -lssl -lcrypto -lz -fPIC

我读了那些命令＆＃34; -lssl -lcrypto -lz ＆＃34;必须添加以修复这些错误，但我把它们放在错误的地方（在lmariadbclient之前）。当我在＆＃34; -lmariadbclient ＆＃34;之后添加它们时我终于能够编译我的程序了：

 mysql --version
 mysql  Ver 15.1 Distrib 10.2.7-MariaDB, for debian-linux-gnu (x86_64) using readline 5.2

更新22.07.2017：

我最近尝试在新的Linux Mint 18.2上编译我的程序。不幸的是我得到了相同的编译错误，我无法使用旧方法修复它：

MariaDB版本：

/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x189): undefined reference to `CRYPTO_num_locks'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1a4): undefined reference to `CRYPTO_THREADID_set_callback'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1b0): undefined reference to `CRYPTO_set_locking_callback'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1b5): undefined reference to `SSL_library_init'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1c1): undefined reference to `SSL_load_error_strings'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1c6): undefined reference to `OPENSSL_add_all_algorithms_noconf'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x2a4): undefined reference to `CRYPTO_set_locking_callback'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x2ab): undefined reference to `CRYPTO_set_id_callback'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x2cf): undefined reference to `CRYPTO_num_locks'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x330): undefined reference to `EVP_cleanup'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x335): undefined reference to `CRYPTO_cleanup_all_ex_data'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x33a): undefined reference to `ERR_free_strings'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x33f): undefined reference to `CONF_modules_free'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_init':
(.text+0x3c1): undefined reference to `SSLv23_client_method'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `my_cb_threadid':
(.text+0x1e): undefined reference to `CRYPTO_THREADID_set_numeric'

编译错误：

g++ -std=c++11 *.cpp ../common/*.cpp ../common/*.c -o myprogram -I.. -ldl -Wstack-protector -fstack-protector-all -pthread -ggdb -lmariadb -Wwrite-strings -lssl -lcrypto -lz -fPIC

我设法通过更改＆＃34; -lmariadbclient ＆＃34;来解决问题。 to：＆＃34; -lmariadb ＆＃34;。之后，我能够编译我的程序，没有错误。我不确定这个解决方案是否适用于所有人，但值得尝试：）

我的最终Makefile是：

{{1}}

祝你好运！

哪个lib用？ libmariadbclient还是libmysqlclient？

1 个答案: