getVar: no visible global function definition for ‘getFromNamespace’
setVar: no visible global function definition for ‘assignInNamespace’
sfApply: no visible global function definition for ‘parApply’
sfClusterApply: no visible global function definition for
  ‘clusterApply’
sfClusterApplyLB: no visible global function definition for
  ‘clusterApplyLB’
sfClusterCall: no visible global function definition for ‘clusterCall’
sfClusterSetupRNG: no visible global function definition for
  ‘clusterSetupRNG’
sfClusterSetupRNGstream: no visible global function definition for
  ‘clusterSetupRNGstream’
sfClusterSetupSPRNG: no visible global function definition for ‘runif’
sfClusterSetupSPRNG: no visible global function definition for
  ‘clusterSetupSPRNG’
sfClusterSplit: no visible global function definition for
  ‘clusterSplit’
sfExport: no visible global function definition for ‘getFromNamespace’
sfExportAll: no visible global function definition for ‘na.omit’
sfInit: no visible global function definition for ‘data’
sfInit: no visible global function definition for
  ‘setDefaultClusterOptions’
sfInit: no visible global function definition for ‘makeCluster’
sfInit: no visible global function definition for ‘makeNWScluster’
sfInit: no visible global function definition for ‘makeMPIcluster’
sfInit: no visible global function definition for ‘packageDescription’
sfLapply: no visible global function definition for ‘parLapply’
sfMM: no visible global function definition for ‘parMM’
sfSapply: no visible global function definition for ‘parSapply’
sfStop: no visible global function definition for ‘stopCluster’
sfTest : testCalc1: no visible global function definition for ‘runif’
sfTest : testCalc2: no visible global function definition for ‘runif’
Undefined global functions or variables:
  assignInNamespace clusterApply clusterApplyLB clusterCall
  clusterSetupRNG clusterSetupRNGstream clusterSetupSPRNG clusterSplit
  data getFromNamespace makeCluster makeMPIcluster makeNWScluster
  na.omit packageDescription parApply parLapply parMM parSapply runif
  setDefaultClusterOptions stopCluster
Consider adding
  importFrom("stats", "na.omit", "runif")
  importFrom("utils", "assignInNamespace", "data", "getFromNamespace",
             "packageDescription")
to your NAMESPACE file.