Infinite recursion of == operation on mutable struct causes Bus error

[tk3369]

A minor error handling issue. I would expect a StackOverflowError but instead it crashed.

julia> mutable struct Bar end

julia> Base.:(==)(a::Bar, b::Bar) = a == b

julia> a = Bar(); b = Bar();

julia> a == b
Bus error: 10

It works fine for immutable struct:

julia> struct Foo end

julia> Base.:(==)(a::Foo, b::Foo) = a == b

julia> a = Foo(); b = Foo();

julia> a == b
ERROR: StackOverflowError:
Stacktrace:
 [1] ==(::Foo, ::Foo) at ./REPL[15]:1 (repeats 80000 times)

[yuyichao]

Likely dup of #17109

[yuyichao]

From the reporter's other post I assume this is on mac and therefore a dup. Feel free to comment if this isn't on a mac.