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.