PRInt32 offset32 = offset;
PRInt32 offset32; LL_L2I(offset32, offset);
NS_IMETHODIMP nsStringInputStream::Seek(PRInt32 whence, PRInt64 offset){    mLastResult = NS_OK; // reset on a seek.    const nsInt64 maxUint32 = PR_UINT32_MAX;    nsInt64 offset64(offset);    PRInt32 offset32 = offset;    NS_ASSERTION(maxUint32 > offset64, "string streams only support 32 bit offsets");    mEOF = PR_FALSE; // reset on a seek.    PRInt32 fileSize = LengthRemaining();    PRInt32 newPosition=-1;    switch (whence)    {        case NS_SEEK_CUR: newPosition = mOffset + offset32; break;        case NS_SEEK_SET: newPosition = offset32; break;        case NS_SEEK_END: newPosition = fileSize + offset32; break;    }    if (newPosition < 0)    {        newPosition = 0;        mLastResult = NS_FILE_RESULT(PR_FILE_SEEK_ERROR);    }    if (newPosition >= fileSize)    {        newPosition = fileSize;        mEOF = PR_TRUE;    }    mOffset = newPosition;    return NS_OK;}