* lukas/compiler/add_to_dis/OTP-14784:
  compiler: Add +to_dis option that dumps loaded asm

The compiler option 'deterministic' was only recognized when given
as an option to the compiler, not when it was specified in a
-compile() attribute in the source file.

https://bugs.erlang.org/browse/ERL-498

4c31fd0b9665 made the merging of match contexts stricter;
in fact, a little bit too strict.

Two match contexts with different number of slots would
be downgraded to the 'term' type. The correct way is to
keep the match context but set the number of slots to the
lowest number of slots of the two match contexts.

https://bugs.erlang.org/browse/ERL-490

* maint-20:
  Updated OTP version
  Prepare release
  Accept non-binary options as socket-options
  Bump version
  Fix broken handling of default values in extensions for PER
  compiler: Fix live regs update on allocate in validator
  Take fail labels into account when determining liveness in block ops
  Check for overflow when appending binaries, and error out with system_limit

* john/compiler/fail-labels-in-blocks-otp-19/ERIERL-48/OTP-14522:
  compiler: Fix live regs update on allocate in validator
  Take fail labels into account when determining liveness in block ops

The sys_core_fold pass would do an unsafe "optimization" when an
apply operation did not have a variable in the function position
as in the following example:

> cat test1.core
module 'test1' ['test1'/2]
    attributes []
'i'/1 =
  fun (_f) -> _f
'test1'/2 =
  fun (_f, _x) ->
    apply apply 'i'/1 (_f) (_x)
end
> erlc test1.core
no_file: Warning: invalid function call

Reported-by: Mikael Pettersson

https://bugs.erlang.org/browse/ERL-433