I want to examine the contents of a std::vector in GDB, how do I do it? Let's say it's a std::vector<int> for the sake of simplicity.
To view vector std::vector myVector contents, just type in GDB:
(gdb) print myVector
This will produce an output similar to:
$1 = std::vector of length 3, capacity 4 = {10, 20, 30}
To achieve above, you need to have gdb 7 (I tested it on gdb 7.01) and some python pretty-printer. Installation process of these is described on gdb wiki.
What is more, after installing above, this works well with Eclipse C++ debugger GUI (and any other IDE using GDB, as I think).
With GCC 4.1.2, to print the whole of a std::vector<int> called myVector, do the following:
print *(myVector._M_impl._M_start)@myVector.size()
To print only the first N elements, do:
print *(myVector._M_impl._M_start)@N
Explanation
This is probably heavily dependent on your compiler version, but for GCC 4.1.2, the pointer to the internal array is:
myVector._M_impl._M_start
And the GDB command to print N elements of an array starting at pointer P is:
print P@N
Or, in a short form (for a standard .gdbinit):
p P@N