prestodb/presto · error · IllegalArgumentException

arrayOffset is negative

Error message

arrayOffset is negative

What it means

ShortArrayBlock stores a shared backing array with an offset window into it; the package-private constructor validates that arrayOffset and positionCount are non-negative so that position indexing (arrayOffset + position) is always in bounds. A negative arrayOffset indicates corrupted slice parameters and fails fast with IllegalArgumentException.

Source

Thrown at presto-common/src/main/java/com/facebook/presto/common/block/ShortArrayBlock.java:57

    public static final int SIZE_IN_BYTES_PER_POSITION = Short.BYTES + Byte.BYTES;

    private final int arrayOffset;
    private final int positionCount;
    @Nullable
    private final boolean[] valueIsNull;
    private final short[] values;

    private final long retainedSizeInBytes;

    public ShortArrayBlock(int positionCount, Optional<boolean[]> valueIsNull, short[] values)
    {
        this(0, positionCount, valueIsNull.orElse(null), values);
    }

    ShortArrayBlock(int arrayOffset, int positionCount, boolean[] valueIsNull, short[] values)
    {
        if (arrayOffset < 0) {
            throw new IllegalArgumentException("arrayOffset is negative");
        }
        this.arrayOffset = arrayOffset;
        if (positionCount < 0) {
            throw new IllegalArgumentException("positionCount is negative");
        }
        this.positionCount = positionCount;

        if (values.length - arrayOffset < positionCount) {
            throw new IllegalArgumentException("values length is less than positionCount");
        }
        this.values = values;

        if (valueIsNull != null && valueIsNull.length - arrayOffset < positionCount) {
            throw new IllegalArgumentException("isNull length is less than positionCount");
        }
        this.valueIsNull = valueIsNull;

        retainedSizeInBytes = INSTANCE_SIZE + sizeOf(valueIsNull) + sizeOf(values);

View on GitHub (pinned to 55bb57d202)

Solutions

1. Check offset arguments are >= 0 before invoking the constructor (or its factory methods)
2. Fix the offset computation (e.g. a start index that went negative) in the calling block code
3. Upgrade/regress to a Presto version without the block-slicing bug if this arises from internal compaction code

Example fix

// before
return new ShortArrayBlock(offset, count, valueIsNull, values); // offset computed, may be negative
// after
checkArgument(offset >= 0, "arrayOffset is negative: %s", offset);
return new ShortArrayBlock(offset, count, valueIsNull, values);

// before constructing ShortArrayBlock (or calling factories that slice)
if (arrayOffset < 0) {
    throw new IllegalArgumentException("arrayOffset computed as " + arrayOffset + " is negative");
}

try {
    return new ShortArrayBlock(arrayOffset, positionCount, valueIsNull, values);
} catch (IllegalArgumentException e) {
    if (e.getMessage().equals("arrayOffset is negative")) {
        throw new IllegalStateException("negative slice offset " + arrayOffset + "; check slicing arithmetic", e);
    }
    throw e;
}

When it happens

Trigger: Constructing ShortArrayBlock with a negative arrayOffset — typically only reachable from internal factory methods (wrapSlice, getRegion copying, block compaction) that compute offsets via subtraction or slicing of a parent block.

Common situations: Custom block code copying regions with wrong start offsets; regression in block compaction/retention logic after block layout changes between Presto versions.

Related errors

• Expected value to contain a single position but has %s posit
• array1 and array2 cannot be null and should have same length
• arrayOffset is negative
• positionCount is negative
• positionCount is negative

AI-assisted analysis of prestodb/presto@55bb57d202 (2026-09-04). Data as JSON: /api/errors/35d3864f2fca3ba6. Report an issue: GitHub.