Bias in R's random integers?

From: Duncan Murdoch <murdoch.duncan at gmail.com>

Let's try it:

  > m <- (2/5)*2^32
  > m > 2^31

[1] FALSE

  > x <- sample(m, 1000000, replace = TRUE)
  > table(x %% 2)

       0      1
399850 600150

Since m is an even number, the true proportions of evens and odds should
be exactly 0.5.  That's some pretty strong evidence of the bug in the
generator.

It seems to be a recently-introduced bug.  Here's output with R-2.15.1:

   R version 2.15.1 (2012-06-22) -- "Roasted Marshmallows"
   Copyright (C) 2012 The R Foundation for Statistical Computing
   ISBN 3-900051-07-0
   Platform: x86_64-unknown-linux-gnu (64-bit)
   
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   You are welcome to redistribute it under certain conditions.
   Type 'license()' or 'licence()' for distribution details.
   
   R is a collaborative project with many contributors.
   Type 'contributors()' for more information and
   'citation()' on how to cite R or R packages in publications.
   
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   Type 'q()' to quit R.
   

   > set.seed(123)
   > m <- (2/5)*2^32
   > m > 2^31

   [1] FALSE

   > x <- sample(m, 1000000, replace = TRUE)
   > table(x %% 2)

   
        0      1
   499412 500588
   
So I doubt that this has anything to do with bias from using 32-bit
random values.