gather() appears significantly slower than corresponding melt about tidyr HOT 2 CLOSED

n <- 1e6
stocks <- data.frame(
  time = as.Date('2009-01-01') + seq_len(n),
  X = rnorm(n, 0, 1),
  Y = rnorm(n, 0, 2),
  Z = rnorm(n, 0, 4)
)

library(microbenchmark)
microbenchmark(
  melt = reshape2::melt(stocks, measure.vars = c('X', 'Y', 'Z')),
  gather = tidyr::gather(stocks, stock, price, -time),
  times = 10
)

# Unit: milliseconds
#    expr      min       lq   median       uq      max neval
#    melt 25.94290 115.8633 122.2179 124.8507 125.4477    10
#  gather 21.38007 121.5440 123.7361 128.5455 129.7107    10