debug 2

 

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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 覆蓋 Symbol Path (不須要記憶官方地址)

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

.sympath (path) : 顯示(覆蓋)當前Symbol Path

Source: src path 只要相對路徑不被破壞，只需指定一處(源文件的根目錄)，windbg會自動關聯。

-        須要的src path一般是包含在pdb文件中，只有在加載pdb後可知，好比打印堆

load executable/ dump file / attach to process
lm 查看模塊及是否加載symbol !lmi module-name 查看模塊的symbol 位置   ~ 顯示thread數  ~ NO. S  切換thread    K顯示堆   .frame NO.  前往指定堆   查找符號斷點 -        根據k 顯示的符號 -        X [<*|module>!]<*|symbol> - view symbols Bp  function-name  & bc 刪除   打開源文件, 若是沒設置對路徑，無反應 .open  -a function-name       調試 g – run  p – step over t – step in   查看變量 dv varialble	i sh 查看加載的動態模塊   Info threads 查看線程 thread NO. 切換線程   bt 堆      frame NO 前往指定堆   查看符號斷點 -        Info functions 查看有的符號 -        b functon-name  / delete NO. 刪除斷點 -        info b 查看breakpoints    Info sources 查看引用source 路徑   Show directories 來查看source search path 使用set directories / substitute-path 來設置目錄  List -  當前行 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