摘要
写这篇文章，主要是因为程序编译的时候遇到的两个问题，花费了半天功夫，其实了解Unix下C、C++程序编译运行原理，这两个问题自然迎刃而解。
内容
1. 问题描述
2. C、C++程序编译原理
3. C++动态库与静态库
1. 问题描述
<span style="font-size:14px;">/usr/bin/ld: warning: libdb2dascmn.so.1, needed by ./lib_third/linux/lib64/libdb2.so, not found (try using -rpath or -rpath-link) /usr/bin/ld: warning: libdb2g11n.so.1, needed by ./lib_third/linux/lib64/libdb2.so, not found (try using -rpath or -rpath-link) /usr/bin/ld: warning: libdb2genreg.so.1, needed by ./lib_third/linux/lib64/libdb2.so, not found (try using -rpath or -rpath-link) /usr/bin/ld: warning: libdb2install.so.1, needed by ./lib_third/linux/lib64/libdb2.so, not found (try using -rpath or -rpath-link) /usr/bin/ld: warning: libdb2locale.so.1, needed by ./lib_third/linux/lib64/libdb2.so, not found (try using -rpath or -rpath-link) /usr/bin/ld: warning: libdb2osse.so.1, needed by ./lib_third/linux/lib64/libdb2.so, not found (try using -rpath or -rpath-link) /usr/bin/ld: warning: libdb2osse_db2.so.1, needed by ./lib_third/linux/lib64/libdb2.so, not found (try using -rpath or -rpath-link) /usr/bin/ld: warning: libdb2trcapi.so.1, needed by ./lib_third/linux/lib64/libdb2.so, not found (try using -rpath or -rpath-link) /usr/bin/ld: warning: libstdc++.so.5, needed by ./lib_third/linux/lib64/libdb2.so, may conflict with libstdc++.so.6 ./lib_third/linux/lib64/libdb2.so: undefined reference to `OSSDecimal64FromString(char const*)' ./lib_third/linux/lib64/libdb2.so: undefined reference to `OSSHLibrary::isLoaded()' ./lib_third/linux/lib64/libdb2.so: undefined reference to `OSS_DECIMAL64_NEG_SNAN' ./lib_third/linux/lib64/libdb2.so: undefined reference to `ossLogRC' ./lib_third/linux/lib64/libdb2.so: undefined reference to `sqlnlssplitcp2' ./lib_third/linux/lib64/libdb2.so: undefined reference to `sqlnlsFormatDate' ./lib_third/linux/lib64/libdb2.so: undefined reference to `OSSDecfloat::fromString(char const*, rounding)' ./lib_third/linux/lib64/libdb2.so: undefined reference to `dfpalInit(void*)' ./lib_third/linux/lib64/libdb2.so: undefined reference to `g_pGTCB' ./lib_third/linux/lib64/libdb2.so: undefined reference to `decimal64Minus(decimal64)' ./lib_third/linux/lib64/libdb2.so: undefined reference to `OSSHFile::read(OSSFileReadParam const*, void*, unsigned long*)' ./lib_third/linux/lib64/libdb2.so: undefined reference to `ossComputeMontgomeryInverse32' ./lib_third/linux/lib64/libdb2.so: undefined reference to `sqlnlsschr' ./lib_third/linux/lib64/libdb2.so: undefined reference to `sqloGetEnvLocale' ./lib_third/linux/lib64/libdb2.so: undefined reference to `decimal128FromNumber(decimal128*, decNumber const*, decContext*)' ./lib_third/linux/lib64/libdb2.so: undefined reference to `gtraceEnable' ./lib_third/linux/lib64/libdb2.so: undefined reference to `sqlnlsgetctryinfo' ./lib_third/linux/lib64/libdb2.so: undefined reference to `OSSHFile::sync()' ./lib_third/linux/lib64/libdb2.so: undefined reference to `OSSTrapFile::OSSTrapFile()' ./lib_third/linux/lib64/libdb2.so: undefined reference to `OSS_DECIMAL64_NAN'</span> |
其实这是一个很明显的错误，主要是因为我在有台服务器上编译没有报错，在另外一台服务器上拉下源码编译的时候就报错，两个环境的依赖的第三方库完全相同，Google 一下设置一下LD_LIBRARY_PATH就好了，当时觉得很奇怪，LD_LIBRARY_PATH不是代码运行时候调用动态库的时候需要设置的，为啥编译的也需要设置？还是自己对这个编译器工作原理的理解有偏差。
下面简单介绍下我对编译器工作原理的理解，有什么不对的地方，还希望大家指正。
