I have a counts dataframe of RNA-seq dataset, and got the gene lengths using this code:

exons = exonsBy(EnsDb.Hsapiens.v86, by="gene")
exons = reduce(exons)
len = sum(width(exons))
INDEX = intersect(rownames(counts),names(len))
geneLengths = len[INDEX ]
counts = counts[INDEX ,]

And used the lengths to normalize the data from counts to TPM, using this code:

rpkm <- apply(X = subset(counts),
               MARGIN = 2,
               FUN = function(x) {
                 10^9 * x / geneLengths / sum(as.numeric(x))
               })

TPM <- apply(rpkm, 2, function(x) x / sum(as.numeric(x)) * 10^6) %>% as.data.frame()

I don't get errors, I do get the normalized data.. but I also get a list of warnings like this:

Warning messages:
1: In 10^9 * x/genelength :
  longer object length is not a multiple of shorter object length
2: In 10^9 * x/genelength :
  longer object length is not a multiple of shorter object length
3: In 10^9 * x/genelength :
  longer object length is not a multiple of shorter object length
4: In 10^9 * x/genelength :
  longer object length is not a multiple of shorter object length
5: In 10^9 * x/genelength :
  longer object length is not a multiple of shorter object length
6: In 10^9 * x/genelength :
  longer object length is not a multiple of shorter object length
7: In 10^9 * x/genelength :
  longer object length is not a multiple of shorter object length
8: In 10^9 * x/genelength :
  longer object length is not a multiple of shorter object length
9: In 10^9 * x/genelength :
  longer object length is not a multiple of shorter object length

And it goes on for about 50 warnings...

Should I pay attention to these warnings? do they affect the normalization process?