warnings is not included by use VERSION (I learned this the hard way, when I ignored a bug because "it can't happen, warnings would have told me") as demonstrated by:

perl -e "use v5.12; my @b; $a = @b[0]"

perl -e "use warnings; my @b; $a = @b[0]"
Scalar value @b[0] better written as $b[0] at -e line 1.
Name "main::a" used only once: possible typo at -e line 1.
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According to Implicit strictures, use VERSION is equivalent to use strict; use feature ':VERSION';, and I don't think anything as been added since. So you can have the list of what is included by looking in %feature::feature_bundle (you can look at the code of feature for more info on that)

Edit: "use VERSION does not load the feature.pm" as quoted by LanX, so %feature::feature_bundle isn't available unless you explicitly call use feature...