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Although the intent of the code may be to assign b to a and test the value of the result for equality to zero, it is very frequently a case of the programmer mistakenly using the assignment operator = instead of the equals operator ==. Consequently, many compilers will warn about this condition, making this coding error detectable by adhering to MSC00-C. Compile cleanly at high warning levels.
Compliant Solution
When the assignment of b to a is not intended, this conditional block is now executed when a is equal to b.
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The CERT Oracle Secure Coding Standard for Java: EXP51-JJG. Do not perform assignments in conditional statements
ISO/IEC TR 24772 "KOA Likely incorrect expressions"
MITRE CWE: CWE-480, "Use of incorrect operator"
Bibliography
[Hatton 1995] Section 2.7.2, "Errors of omission and addition"
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