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15.4.1.7 gdb Features for C++

Some gdb commands are particularly useful with C++, and some are designed specifically for use with C++. Here is a summary:

breakpoint menus
When you want a breakpoint in a function whose name is overloaded, gdb has the capability to display a menu of possible breakpoint locations to help you specify which function definition you want. See Ambiguous Expressions.


rbreak regex
Setting breakpoints using regular expressions is helpful for setting breakpoints on overloaded functions that are not members of any special classes. See Setting Breakpoints.


catch throw
catch catch
Debug C++ exception handling using these commands. See Setting Catchpoints.


ptype typename
Print inheritance relationships as well as other information for type typename. See Examining the Symbol Table.
info vtbl expression.
The info vtbl command can be used to display the virtual method tables of the object computed by expression. This shows one entry per virtual table; there may be multiple virtual tables when multiple inheritance is in use.


set print demangle
show print demangle
set print asm-demangle
show print asm-demangle
Control whether C++ symbols display in their source form, both when displaying code as C++ source and when displaying disassemblies. See Print Settings.
set print object
show print object
Choose whether to print derived (actual) or declared types of objects. See Print Settings.
set print vtbl
show print vtbl
Control the format for printing virtual function tables. See Print Settings. (The vtbl commands do not work on programs compiled with the HP ANSI C++ compiler (aCC).)


set overload-resolution on
Enable overload resolution for C++ expression evaluation. The default is on. For overloaded functions, gdb evaluates the arguments and searches for a function whose signature matches the argument types, using the standard C++ conversion rules (see C++ Expressions, for details). If it cannot find a match, it emits a message.
set overload-resolution off
Disable overload resolution for C++ expression evaluation. For overloaded functions that are not class member functions, gdb chooses the first function of the specified name that it finds in the symbol table, whether or not its arguments are of the correct type. For overloaded functions that are class member functions, gdb searches for a function whose signature exactly matches the argument types.


show overload-resolution
Show the current setting of overload resolution.
Overloaded symbol names
You can specify a particular definition of an overloaded symbol, using the same notation that is used to declare such symbols in C++: type symbol(types) rather than just symbol. You can also use the gdb command-line word completion facilities to list the available choices, or to finish the type list for you. See Command Completion, for details on how to do this.