diff --git a/base/abstractdict.jl b/base/abstractdict.jl
index 76627d44756991..514bf53b7db6fc 100644
--- a/base/abstractdict.jl
+++ b/base/abstractdict.jl
@@ -560,6 +560,9 @@ Modifies `dict` by transforming each value from `val` to `f(val)`.
 Note that the type of `dict` cannot be changed: if `f(val)` is not an instance of the value type
 of `dict` then it will be converted to the value type if possible and otherwise raise an error.
 
+!!! compat "Julia 1.2"
+    `map!(f, values(dict::AbstractDict))` requires Julia 1.2 or later.
+
 # Examples
 ```jldoctest
 julia> d = Dict(:a => 1, :b => 2)