Do not use a semicolon on the same line as an if, for, or while statement because 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 an if statement:

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

Compliant Solution

It is likely, in this example, that the semicolon was accidentally inserted:

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

Risk Assessment

Errors of omission can result in unintended program flow.

Recommendation

Severity

Likelihood

Remediation Cost

Priority

Level

EXP15-C

High

Likely

Low

P27

L1


Automated Detection

Tool

Version

Checker

Description

CodeSonar
LANG.STRUCT.EBSEmpty branch statement
Klocwork

SEMICOL


LDRA tool suite
11 S, 12 S, 428 SFully Implemented
Parasoft C/C++test
CERT-EXP-19Fully implemented
PRQA QA-C
3109
PVS-Studio

V529, V715
SonarQube C/C++ Plugin
S1116

Related Guidelines

SEI CERT Oracle Coding Standard for JavaMSC51-J. Do not place a semicolon immediately following an if, for, or while condition
ISO/IEC TR 24772:2013Likely Incorrect Expression [KOA]
MITRE CWECWE-480, Use of incorrect operator

Bibliography

[Hatton 1995]Section 2.7.2, "Errors of Omission and Addition"