Remove sys_pre_expand

The previous commits have made sys_pre_expand superfluous. Since
sys_pre_expand is undocumented and unsupported it can be removed in
a major release without prior deprecation.

Also remove code in erl_parse that handles abstract code that has
passed through sys_pre_expand.

We considered deprecating sys_pre_expand just in case, but decided
against it for the following reasons:

- Anyone brave and knowledgeable enough to use sys_pre_expand should
be able to cope with sys_pre_expand being removed.

- If we kept it, but didn't test it anywhere in OTP, it could
potentially stop working. So we would probably have to add some test
cases.

1 files changed, 0 insertions, 13 deletions

diff --git a/lib/stdlib/src/erl_parse.yrl b/lib/stdlib/src/erl_parse.yrl
index 85b2816451..549179da68 100644
--- a/lib/stdlib/src/erl_parse.yrl
+++ b/lib/stdlib/src/erl_parse.yrl
@@ -1567,19 +1567,6 @@ anno_from_term(Term) ->
     map_anno(fun erl_anno:from_term/1, Term).
 
 %% Forms.
-%% Recognize what sys_pre_expand does:
-modify_anno1({'fun',A,F,{_,_,_}=Id}, Ac, Mf) ->
-    {A1,Ac1} = Mf(A, Ac),
-    {F1,Ac2} = modify_anno1(F, Ac1, Mf),
-    {{'fun',A1,F1,Id},Ac2};
-modify_anno1({named_fun,A,N,F,{_,_,_}=Id}, Ac, Mf) ->
-    {A1,Ac1} = Mf(A, Ac),
-    {F1,Ac2} = modify_anno1(F, Ac1, Mf),
-    {{named_fun,A1,N,F1,Id},Ac2};
-modify_anno1({attribute,A,N,[V]}, Ac, Mf) ->
-    {{attribute,A1,N1,V1},Ac1} = modify_anno1({attribute,A,N,V}, Ac, Mf),
-    {{attribute,A1,N1,[V1]},Ac1};
-%% End of sys_pre_expand special forms.
 modify_anno1({function,F,A}, Ac, _Mf) ->
     {{function,F,A},Ac};
 modify_anno1({function,M,F,A}, Ac, Mf) ->