The page: http://root.cern.ch/root/html/TPad.html says:
Examples:
gStyle->SetPaperSize(kA4); //default
gStyle->SetPaperSize(kUSLetter);
where kA4 and kUSLetter are defined in the enum EPaperSize in TStyle.h
while it should be:
Examples:
gStyle->SetPaperSize(TStyle::kA4); //default
gStyle->SetPaperSize(TStyle::kUSLetter);
where TStyle::kA4 and TStyle::kUSLetter are defined in the enum EPaperSize in TStyle.h
The same problem is possibly present elsewhere.