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What are all the things I will need to check while analyzing core dump file? Please tell me from scratch.
You just need a binary (with debugging symbols included) that is identical to the one that generated the core. Then you can run gdb path/to/the/binary path/to/the/core to debug it.
When it starts up, you can use bt (for backtrace) to get a stack trace from the time of the crash. In the backtrace, each function invocation is given a number. You can use frame number (replacing number with the corresponding number in the stack trace) to select a particular stack frame. You can then use list to see code around that function, and info locals to see the local variables. You can also use print name_of_variable (replacing "name_of_variable" with a variable name) to see its value.
Typing help within GDB will give you a prompt that will let you see additional commands.
Steps to debug coredump using GDB:
Some generic help:
gdb start GDB, with no debugging les
gdb program begin debugging program
gdb program core debug coredump core produced by program
gdb --help describe command line options
1- First of all find the directory where the corefile is generated.
2- Then use ls -ltr command in the directory to find the latest generated corefile.
3- To load the corefile use
gdb binary path of corefile
This will load the corefile.
4- Then you can get the information using bt command.
For detailed backtrace use bt full.
5- To print the variables use print variable-name or p variable-name
6- To get any help on GDB, use the help option or use apropos search-topic
7- Use frame frame-number to go to the desired frame number.
8- Use up n and down n commands to select frame n frames up and select frame n frames down respectively.
9- To stop GDB, use quit or q.
来源：https://stackoverflow.com/questions/5115613/core-dump-file-analysis