How to inspect std::string in GDB with no source code?

c++ stl gdb std c++-standard-library
PeterBelm picture PeterBelm · Jul 21, 2011 · Viewed 18.9k times · Source

I'm trying to debug a program that has no source code available, and I need to look at what it has stored in a std::string. I've been Googling and looking on here, and I've found some information about outputting STL containers, but all of it refers to variables, with no source or debug information all I have is a memory offset of the class data. Is there any way to do this?

Answer

Employed Russian picture Employed Russian · Jul 21, 2011

Every std::string implementation has a pointer to the raw characters in it somewhere. For g++ 4.x, that pointer is at offset 0 into the string.

If you know that the string resides at e.g. 0x7fffffffda88, then

print *(char**)0x7fffffffda88

is what you need.

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