14.19

Unreachable Statements

BLOCKS AND STATEMENTS

A local variable declaration statement can complete normally iff it is reach 

able.

An empty statement can complete normally iff it is reachable.

A labeled statement can complete normally if at least one of the following is

true:

N

The contained statement can complete normally.

N

There is a reachable

break

 statement that exits the labeled statement.

The contained statement is reachable iff the labeled statement is reachable.

An expression statement can complete normally iff it is reachable.

The

if

 statement, whether or not it has an

else

 part, is handled in an unusual

manner. For this reason, it is discussed separately at the end of this section.

A

switch

 statement can complete normally iff at least one of the following is

true:

N

The last statement in the switch block can complete normally.

N

The switch block is empty or contains only switch labels.

N

There is at least one switch label after the last switch block statement group.

N

There is a reachable

break

 statement that exits the

switch

 statement.

A switch block is reachable iff its

switch

 statement is reachable.

A statement in a switch block is reachable iff its

switch

 statement is reach 

able and at least one of the following is true:

N

It bears a

case

 or

default

 label.

N

There is a statement preceding it in the

switch

 block and that preceding

statement can complete normally.

A

while

 statement can complete normally iff at least one of the following is

true:

N

The

while

 statement is reachable and the condition expression is not a con 

stant expression with value

true

.

N

There is a reachable

break

 statement that exits the

while

 statement.

The contained statement is reachable iff the

while

 statement is reachable and

the condition expression is not a constant expression whose value is

false

.

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