debug 2

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delivers the latest stable versions of essential GCC C, C++, Fortran, and supporting development
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About GCC version, recommend to use the latest version,
wihle adding new features to compiler, it may introduce some ABI changes and new defects(especially c++11)
if we use a third-party lib complied with gcc of a different version, sometimes it may cause link failure(backwards compatibility).
https://gcc.gnu.org/onlinedocs/libstdc++/manual/abi.html (part 3)
https://gcc.gnu.org/wiki/Cxx11AbiCompatibility
https://gcc.gnu.org/onlinedocs/libstdc++/manual/using_dual_abi.html

linux so information:
readelf vs objdump : recommend to use readelf
https://stackoverflow.com/questions/8979664/readelf-vs-objdump-why-are-both-needed

direct dependency: readelf -d
recursive ones : ldd

elf sections: .comment debug symtab text
gcc version : readelf -p .comment elf-file

check whether elf is compiled with '-g' (debugging)
1) use gdb
2） readelf -S elf //to see if there are .debug_x sections
- readelf --debug-dump=decodeline elf // to show section:.debug_line

3)if Elf are built with '-gsplit-dwarf', it would generate *.dwo to contain debug info
find its path in .debug_str

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Windbg 概念

Local cache     MS Symbol Store     Symbol (search) Path

.symfix (path) : 把 Store 覆盖 Symbol Path (不需要记忆官方地址)

.symfix+ path : 把Store 添加到已有Symbol Path

.sympath (path) : 显示(覆盖)当前Symbol Path

Source: src path 只要相对路径不被破坏，只需指定一处(源文件的根目录)，windbg会自动关联。

-        需要的src path通常是包含在pdb文件中，只有在加载pdb后可知，比如打印堆

load executable/ dump file / attach to process
lm 查看模块及是否加载symbol !lmi module-name 查看模块的symbol 位置 ~ 显示thread数  ~ NO. S  切换thread K显示堆   .frame NO.  前往指定堆 查找符号断点 -        根据k 显示的符号 -        X [<*|module>!]<*|symbol> - view symbols Bp  function-name  & bc 删除 打开源文件, 如果没设置对路径，无反应 .open  -a function-name 调试 g – run  p – step over t – step in 查看变量 dv varialble	i sh 查看加载的动态模块 Info threads 查看线程 thread NO. 切换线程 bt 堆      frame NO 前往指定堆 查看符号断点 -        Info functions 查看有的符号 -        b functon-name  / delete NO. 删除断点 -        info b 查看breakpoints Info sources 查看引用source 路径   Show directories 来查看source search path 使用set directories / substitute-path 来设置目录 List -  当前行 list function / NO. Debug r – run   n – step over  s  - step into   c - continue Variables p variable  set variable = new-v
提供了 查看map, list 命令	Info args  / where  / condition  / (force) return