Why would a register variable always be placed in the register?

Local variables are stored in registers in most cases, because registers are pushed and poped from stack when you make function calls It looks like they are on stack.

Can we access the address of a register variable yes or no?

It’s that statement in the standard that makes it illegal to take the address of a register variable. The rule is enforced, even if the compiler doesn’t assign the variable to a CPU register.

Why register storage class is considered as a request?

The register storage class specifier is typically specified for heavily used variables, such as a loop control variable, in the hopes of enhancing performance by minimizing access time. However, the compiler is not required to honor this request.

Why a register variable should not be used?

A register is a sort of variable used by CPU, very very fast in access because it isn’t located in memory (RAM). The use of a register is limited by the architecture and the size of the register itself (this mean that some could be just like memory pointers, other to load special debug values and so on).

What is the scope of register variable?

Register variables: belong to the register storage class and are stored in the CPU registers. The scope of the register variables is local to the block in which the variables are defined. The variables which are used for more number of times in a program are declared as register variables for faster access.

Where are register variables stored in memory?

Register variables are stored in the CPU registers. Its default value is a garbage value. Scope of a register variable is local to the block in which it is defined. Lifetime is till control remains within the block in which the register variable is defined.

What are register variables What are the advantage of using register variables?

Advantages of Register variable: – Access optimization and speed of program execution: The operations of these variables are faster by orders of magnitude. – It is useful when you want to refer a variable frequently. – It allocates fast memory in the form of a register. – It helps to speed up program execution.

Why is address of register variable not accessible?

1) If you use & operator with a register variable then compiler may give an error or warning (depending upon the compiler you are using), because when we say a variable is a register, it may be stored in a register instead of memory and accessing address of a register is invalid.

How can you access the address of register variable in C?

C and C++ are different languages.

1. In C, you cannot take the address of a variable with register storage. Cf.
2. In C++, register is a deprecated, meaningless keyword that has no effect (except perhaps serve as a compiler hint), and variables declared as register still just have automatic storage.

Can register storage class be specified to global variables?

Register storage class can be specified to global variables. Explanation: None.

When should we use the register storage specifier?

If a variable is used most frequently then it should be declared using register storage specifier, then possibly the compiler gives CPU register for its storage to speed up the look up of the variable.