Red Hat ENTERPRISE LINUX 3 - SECURITY GUIDE, Manual

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Chapter 14. Using gdb with Different Languages 115
==, !=
Equality and inequality. Defined on scalar types. The value of these expressions is 0 for false and
non-zero for true.
2
,
3
,
2
=,
3
=
Less than, greater than, less than or equal, greater than or equal. Defined on scalar types. The
value of these expressions is 0 for false and non-zero for true.
22
,
33
left shift, and right shift. Defined on integral types.
@
The gdb "artificial array" operator (refer to Section 10.1 Expressions ).
+, -
Addition and subtraction. Defined on integral types, floating-point types and pointer types.
*, /, %
Multiplication, division, and modulus. Multiplication and division are defined on integral and
floating-point types. Modulus is defined on integral types.
++, -
Increment and decrement. When appearing before a variable, the operation is performed before
the variable is used in an expression; when appearing after it, the variable’s value is used before
the operation takes place.
*
Pointer dereferencing. Defined on pointer types. Same precedence as
++
.
&
Address operator. Defined on variables. Same precedence as
++
.
For debugging C ++ , gdb implements a use of
&
beyond what is allowed in the C ++ language
itself: you can use
&(&
ref
)
(or, if you prefer, simply
&&
ref
) to examine the address where a
C ++ reference variable (declared with
&
ref
) is stored.
-
Negative. Defined on integral and floating-point types. Same precedence as
++
.
!
Logical negation. Defined on integral types. Same precedence as
++
.
~
Bitwise complement operator. Defined on integral types. Same precedence as
++
.
., -
3
Structure member, and pointer-to-structure member. For convenience, gdb regards the two as
equivalent, choosing whether to dereference a pointer based on the stored type information. De-
fined on
struct
and
union
data.