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H.3.2 Pragma Inspection_Point

An occurrence of a pragma Inspection_Point identifies a set of objects each of whose values is to be available at the point(s) during program execution corresponding to the position of the pragma in the compilation unit. The purpose of such a pragma is to facilitate code validation. 


The form of a pragma Inspection_Point is as follows: 
  pragma Inspection_Point[(object_name {, object_name})];

Legality Rules

A pragma Inspection_Point is allowed wherever a declarative_item or statement is allowed. Each object_name shall statically denote the declaration of an object. 

Static Semantics

An inspection point is a point in the object code corresponding to the occurrence of a pragma Inspection_Point in the compilation unit. An object is inspectable at an inspection point if the corresponding pragma Inspection_Point either has an argument denoting that object, or has no arguments and the declaration of the object is visible at the inspection point. 

Dynamic Semantics

Execution of a pragma Inspection_Point has no effect.

Implementation Requirements

Reaching an inspection point is an external interaction with respect to the values of the inspectable objects at that point (see 1.1.3). 

Documentation Requirements

For each inspection point, the implementation shall identify a mapping between each inspectable object and the machine resources (such as memory locations or registers) from which the object's value can be obtained. 
7  The implementation is not allowed to perform “dead store elimination” on the last assignment to a variable prior to a point where the variable is inspectable. Thus an inspection point has the effect of an implicit read of each of its inspectable objects.
8  Inspection points are useful in maintaining a correspondence between the state of the program in source code terms, and the machine state during the program's execution. Assertions about the values of program objects can be tested in machine terms at inspection points. Object code between inspection points can be processed by automated tools to verify programs mechanically. 
9  The identification of the mapping from source program objects to machine resources is allowed to be in the form of an annotated object listing, in human-readable or tool-processable form. 

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