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Do not use a semicolon on the same line as after an if, for, or while statement condition because this it typically indicates programmer error and can result in unexpected behavior.

Noncompliant Code Example

In this noncompliant code example, a semicolon is used on the same line as immediately following an if statement. condition:

if (a == b); {
  /* ... */
}

The statements in the apparent body of the if statement are always evaluated regardless of the result of the condition expression.

Compliant Solution

It is likely, in this example, that the semicolon was accidentally inserted.This compliant solution eliminates the semicolon and ensures that the body of the if statement is executed only when the condition expression is true:

if (a == b) {
  /* ... */
}

Related Guidelines

Applicability

Placing a semicolon immediately following

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CERT C Secure Coding Standard

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an if, for, or while

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<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="e4a8016b-11f8-433f-ad64-420db8a61a4e"><ac:plain-text-body><![CDATA[

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[ISO/IEC TR 24772:2010

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http://www.aitcnet.org/isai/]

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"Likely Incorrect Expression [java:KOA]"

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]]></ac:plain-text-body></ac:structured-macro>

condition may result in unexpected behavior.

Automated Detection

Bibliography

Bibliography

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Image Added Image Added Image AddedMSC05-J. Do not leak memory      49. Miscellaneous (MSC)      MSC07-J. Do not assume infinite heap space