False positive after macro usage

[Lukas Sommer]

Consider the following code:

    QStringList candidates;

ifdef Q_OS_DARWIN

    candidates.append(QStringLiteral(u"/color/icc/"));

elif defined(Q_OS_UNIX)

    candidates.append(QStringLiteral(u"/color/icc/"));

elif defined(Q_OS_WIN)

    candidates.append(QStringLiteral(u"/color/icc/"));

endif

    int i = 0;
    for (const QString &path : candidates) {
        if (path.isEmpty()) {
            i = i * 3;
        }
    }

cppcheck now complains:

"Iterating over container 'candidates' that is always empty. (CWE-398)"

However, 'candidates' is not empty for at least many platforms.

Lukas Sommer

[CHR]

Have you considered passing e.g. -DQ_OS_DARWIN to cppcheck?

[Lukas Sommer]

Wouldn't this implicitly disable cppcheck for the other paths (Q_OS_UNIX and Q_OS_WIN) for the hole project?

If I want to avoid this, maybe I could “--inline-suppr” and manually suppress this single warning for this line of the code? This might the better choice for me because I have only one offending line with a theoretically possibly empty container, but I have much more lines in the different code paths which could profit from cppcheck.