In this section:

Overview

This error is generated whenever an expression operates on an uninitialized pointer.

Code Description Enabled Reported Platform EXPR_UNINIT_PTR Expression uses uninitialized pointer Runtime Windows/Unix

Problem

In the following code uses an uninitialized pointer.

/*
 * File: expuptr.c
 */
main()
	{
		char *a, b[10], c[10];
		if (a > b)
		a = b;
		return (0);
	}

Diagnosis at Runtime

[expuptr.c:8] **EXPR_UNINIT_PTR**
>>			 if (a > b)
Expression uses uninitialized pointer: a > b

---- Associated Common Weakness Enumerations ----
CWE-457: Use of uninitialized variable
CWE-824: Access of uninitialized pointer
CWE-908: Use of uninitialized resource

Stack trace where the error occurred:
		main() expuptr.c, 8

• Line 1: Source line at which the problem was detected.
• Line 3: Description of the problem and the expression that is in error.
• Line 5-8: CWEs associated with the problem.
• Line 10: Stack trace showing the function call sequence leading to the error.

Repair

This error is normally caused by omitting an assignment statement for the uninitialized variable. The example code can be corrected as follows:

/*
 * File: expuptr.c (modified)
 */
main()
	{
		char *a, b[10], c[10];
		a = c;
		if (a > b)
		a = b;
		return (0);
	}

References

The table below shows Common Weakness Enumerations associated with this error.