diff --git a/base/boot.jl b/base/boot.jl
index 88a4e7438671e..07b3caec957e1 100644
--- a/base/boot.jl
+++ b/base/boot.jl
@@ -259,18 +259,21 @@ else
     const UInt = UInt32
 end
 
-function iterate end
 function Typeof end
 ccall(:jl_toplevel_eval_in, Any, (Any, Any),
       Core, quote
       (f::typeof(Typeof))(x) = ($(_expr(:meta,:nospecialize,:x)); isa(x,Type) ? Type{x} : typeof(x))
       end)
 
+function iterate end
+
 macro nospecialize(x)
     _expr(:meta, :nospecialize, x)
 end
 Expr(@nospecialize args...) = _expr(args...)
 
+macro worldinc() Expr(:worldinc) end
+
 _is_internal(__module__) = __module__ === Core
 # can be used in place of `@assume_effects :total` (supposed to be used for bootstrapping)
 macro _total_meta()
@@ -517,6 +520,7 @@ eval(Core, quote
     InterConditional(slot::Int, @nospecialize(thentype), @nospecialize(elsetype)) = $(Expr(:new, :InterConditional, :slot, :thentype, :elsetype))
     MethodMatch(@nospecialize(spec_types), sparams::SimpleVector, method::Method, fully_covers::Bool) = $(Expr(:new, :MethodMatch, :spec_types, :sparams, :method, :fully_covers))
 end)
+@worldinc
 
 const NullDebugInfo = DebugInfo(:none)
 
diff --git a/base/essentials.jl b/base/essentials.jl
index efae59b82b5f9..e0d9159cf9ab6 100644
--- a/base/essentials.jl
+++ b/base/essentials.jl
@@ -467,10 +467,20 @@ Evaluate an expression with values interpolated into it using `eval`.
 If two arguments are provided, the first is the module to evaluate in.
 """
 macro eval(ex)
-    return Expr(:escape, Expr(:call, GlobalRef(Core, :eval), __module__, Expr(:quote, ex)))
+    g = ccall(:jl_gensym, Ref{Symbol}, ())
+    return Expr(:let, Expr(:(=), g,
+            Expr(:escape, Expr(:call, GlobalRef(Core, :eval), __module__, Expr(:quote, ex)))),
+        Expr(:block,
+            Expr(:var"worldinc-if-toplevel"),
+            g))
 end
 macro eval(mod, ex)
-    return Expr(:escape, Expr(:call, GlobalRef(Core, :eval), mod, Expr(:quote, ex)))
+    g = ccall(:jl_gensym, Ref{Symbol}, ())
+    return Expr(:let, Expr(:(=), g,
+            Expr(:escape, Expr(:call, GlobalRef(Core, :eval), mod, Expr(:quote, ex)))),
+        Expr(:block,
+            Expr(:var"worldinc-if-toplevel"),
+            g))
 end
 
 # use `@eval` here to directly form `:new` expressions avoid implicit `convert`s
diff --git a/base/sysimg.jl b/base/sysimg.jl
index 476b9715b7e11..6b52cbc65a5b5 100644
--- a/base/sysimg.jl
+++ b/base/sysimg.jl
@@ -16,6 +16,7 @@ using .Base
 
 # Set up Main module
 using Base.MainInclude # ans, err, and sometimes Out
+Core.@worldinc
 
 # These definitions calls Base._include rather than Base.include to get
 # one-frame stacktraces for the common case of using include(fname) in Main.
@@ -39,6 +40,13 @@ actually evaluates `mapexpr(expr)`.  If it is omitted, `mapexpr` defaults to [`i
 
 Use [`Base.include`](@ref) to evaluate a file into another module.
 
+!!! note
+    Julia's syntax lowering recognizes an explicit call to a literal `include`
+    at top-level and inserts an implicit `@Core.worldinc` to make any include'd
+    definitions visible to subsequent code. Note however that this recognition
+    is *syntactic*. I.e. assigning `const myinclude = include` may require
+    and explicit `@Core.worldinc` call after `myinclude`.
+
 !!! compat "Julia 1.5"
     Julia 1.5 is required for passing the `mapexpr` argument.
 """
diff --git a/base/tuple.jl b/base/tuple.jl
index 3791d74bfc698..ee3174d783531 100644
--- a/base/tuple.jl
+++ b/base/tuple.jl
@@ -60,7 +60,7 @@ end
 
 function _setindex(v, i::Integer, args::Vararg{Any,N}) where {N}
     @inline
-    return ntuple(j -> ifelse(j == i, v, args[j]), Val{N}())
+    return ntuple(j -> ifelse(j == i, v, args[j]), Val{N}())::NTuple{N, Any}
 end
 
 
diff --git a/src/ast.c b/src/ast.c
index ea1de429a946c..51dc6d4680c8c 100644
--- a/src/ast.c
+++ b/src/ast.c
@@ -119,6 +119,7 @@ JL_DLLEXPORT jl_sym_t *jl_release_sym;
 JL_DLLEXPORT jl_sym_t *jl_acquire_release_sym;
 JL_DLLEXPORT jl_sym_t *jl_sequentially_consistent_sym;
 JL_DLLEXPORT jl_sym_t *jl_uninferred_sym;
+JL_DLLEXPORT jl_sym_t *jl_worldinc_sym;
 
 static const uint8_t flisp_system_image[] = {
 #include <julia_flisp.boot.inc>
@@ -461,6 +462,7 @@ void jl_init_common_symbols(void)
     jl_acquire_release_sym = jl_symbol("acquire_release");
     jl_sequentially_consistent_sym = jl_symbol("sequentially_consistent");
     jl_uninferred_sym = jl_symbol("uninferred");
+    jl_worldinc_sym = jl_symbol("worldinc");
 }
 
 JL_DLLEXPORT void jl_lisp_prompt(void)
diff --git a/src/interpreter.c b/src/interpreter.c
index f9d981687c631..a85627268894d 100644
--- a/src/interpreter.c
+++ b/src/interpreter.c
@@ -463,8 +463,6 @@ static jl_value_t *eval_body(jl_array_t *stmts, interpreter_state *s, size_t ip,
         s->ip = ip;
         if (ip >= ns)
             jl_error("`body` expression must terminate in `return`. Use `block` instead.");
-        if (toplevel)
-            ct->world_age = jl_atomic_load_acquire(&jl_world_counter);
         jl_value_t *stmt = jl_array_ptr_ref(stmts, ip);
         assert(!jl_is_phinode(stmt));
         size_t next_ip = ip + 1;
@@ -643,6 +641,9 @@ static jl_value_t *eval_body(jl_array_t *stmts, interpreter_state *s, size_t ip,
                     jl_eval_const_decl(s->module, jl_exprarg(stmt, 0), val);
                     s->locals[jl_source_nslots(s->src) + s->ip] = jl_nothing;
                 }
+                else if (head == jl_worldinc_sym) {
+                    ct->world_age = jl_atomic_load_acquire(&jl_world_counter);
+                }
                 else if (jl_is_toplevel_only_expr(stmt)) {
                     jl_toplevel_eval(s->module, stmt);
                 }
@@ -887,10 +888,7 @@ jl_value_t *NOINLINE jl_interpret_toplevel_thunk(jl_module_t *m, jl_code_info_t
     s->mi = NULL;
     s->ci = NULL;
     JL_GC_ENABLEFRAME(s);
-    jl_task_t *ct = jl_current_task;
-    size_t last_age = ct->world_age;
     jl_value_t *r = eval_body(stmts, s, 0, 1);
-    ct->world_age = last_age;
     JL_GC_POP();
     return r;
 }
diff --git a/src/jlfrontend.scm b/src/jlfrontend.scm
index 808af18ebfdbd..3d46940d6fcbb 100644
--- a/src/jlfrontend.scm
+++ b/src/jlfrontend.scm
@@ -139,7 +139,7 @@
 
 (define (toplevel-only-expr? e)
   (and (pair? e)
-       (or (memq (car e) '(toplevel line module import using export public
+       (or (memq (car e) '(toplevel line module export public
                                     error incomplete))
            (and (memq (car e) '(global const)) (every symbol? (cdr e))))))
 
diff --git a/src/julia-syntax.scm b/src/julia-syntax.scm
index 7acc8a1954bc5..d05cb282de30b 100644
--- a/src/julia-syntax.scm
+++ b/src/julia-syntax.scm
@@ -1038,6 +1038,7 @@
                                '())))))
          (call (core _typebody!) ,name (call (core svec) ,@(insert-struct-shim field-types name)))
          (const (globalref (thismodule) ,name) ,name)
+         (worldinc)
          (null)))
        ;; "inner" constructors
        (scope-block
@@ -1087,6 +1088,7 @@
                (call (core _equiv_typedef) (globalref (thismodule) ,name) ,name))
            (null)
            (const (globalref (thismodule) ,name) ,name))
+       (worldinc)
        (null))))))
 
 (define (primitive-type-def-expr n name params super)
@@ -1107,6 +1109,7 @@
                (call (core _equiv_typedef) (globalref (thismodule) ,name) ,name))
            (null)
            (const (globalref (thismodule) ,name) ,name))
+       (worldinc)
        (null))))))
 
 ;; take apart a type signature, e.g. T{X} <: S{Y}
@@ -1221,7 +1224,7 @@
     (cond ((and (length= e 2) (or (symbol? name) (globalref? name)))
            (if (not (valid-name? name))
                (error (string "invalid function name \"" name "\"")))
-           `(method ,name))
+           `(block (method ,name) (worldinc) (unnecessary ,name)))
           ((not (pair? name))  e)
           ((eq? (car name) 'call)
            (let* ((raw-typevars (or where '()))
@@ -2744,6 +2747,9 @@
                  ((and (eq? (identifier-name f) '^) (length= e 4) (integer? (cadddr e)))
                   (expand-forms
                    `(call (top literal_pow) ,f ,(caddr e) (call (call (core apply_type) (top Val) ,(cadddr e))))))
+                 ((eq? f 'include)
+                  (let ((r (make-ssavalue)))
+                    `(block (= ,r ,(map expand-forms e)) (worldinc-if-toplevel) ,r)))
                  (else
                   (map expand-forms e))))
          (map expand-forms e)))
@@ -4125,7 +4131,8 @@ f(x) = yt(x)
                                      `(lambda ,(cadr lam2)
                                         (,(clear-capture-bits (car vis))
                                          ,@(cdr vis))
-                                        ,body)))))
+                                        ,body)))
+                          (worldinc)))
                        (else
                         (let* ((exprs     (lift-toplevel (convert-lambda lam2 '|#anon| #t '() #f parsed-method-stack)))
                                (top-stmts (cdr exprs))
@@ -4133,7 +4140,8 @@ f(x) = yt(x)
                           `(toplevel-butfirst
                             (block ,@sp-inits
                                    (method ,(cadr e) ,(cl-convert sig fname lam namemap defined toplevel interp opaq parsed-method-stack globals locals)
-                                           ,(julia-bq-macro newlam)))
+                                           ,(julia-bq-macro newlam))
+                                   (worldinc))
                             ,@top-stmts))))
 
                  ;; local case - lift to a new type at top level
@@ -4272,7 +4280,8 @@ f(x) = yt(x)
                        `(toplevel-butfirst
                          (null)
                          ,@sp-inits
-                         ,@mk-method)
+                         ,@mk-method
+                         (worldinc))
                        (begin
                          (put! defined name #t)
                          `(toplevel-butfirst
@@ -4280,7 +4289,8 @@ f(x) = yt(x)
                            ,@typedef
                            ,@(map (lambda (v) `(moved-local ,v)) moved-vars)
                            ,@sp-inits
-                           ,@mk-method))))))))
+                           ,@mk-method
+                           (worldinc)))))))))
           ((lambda)  ;; happens inside (thunk ...) and generated function bodies
            (for-each (lambda (vi) (vinfo:set-asgn! vi #t))
                      (list-tail (car (lam:vinfo e)) (length (lam:args e))))
@@ -4512,6 +4522,7 @@ f(x) = yt(x)
           ((struct_type)       "\"struct\" expression")
           ((method)            "method definition")
           ((set_binding_type!) (string "type declaration for global \"" (deparse (cadr e)) "\""))
+          ((worldinc)          "World age increment")
           (else                (string "\"" h "\" expression"))))
       (if (not (null? (cadr lam)))
           (error (string (head-to-text (car e)) " not at top level"))))
@@ -4963,7 +4974,12 @@ f(x) = yt(x)
                      (else  (emit temp)))))
 
             ;; top level expressions
-            ((thunk module)
+            ((thunk)
+             (check-top-level e)
+             (emit e)
+             (if tail (emit-return tail '(null)))
+             '(null))
+            ((module)
              (check-top-level e)
              (emit e)
              (if tail (emit-return tail '(null)))
@@ -4979,8 +4995,22 @@ f(x) = yt(x)
                (if tail (emit-return tail val))
                val))
 
+            ((worldinc-if-toplevel)
+             (if (null? (cadr lam))
+               (emit `(worldinc)))
+             '(null))
+
+            ((import using)
+             (check-top-level e)
+             (emit e)
+             (emit `(worldinc))
+             (let ((have-ret? (and (pair? code) (pair? (car code)) (eq? (caar code) 'return))))
+               (if (and tail (not have-ret?))
+                   (emit-return tail '(null))))
+             '(null))
+
             ;; other top level expressions
-            ((import using export public)
+            ((export public worldinc)
              (check-top-level e)
              (emit e)
              (let ((have-ret? (and (pair? code) (pair? (car code)) (eq? (caar code) 'return))))
diff --git a/src/julia_internal.h b/src/julia_internal.h
index 5eb99be9e333f..31819410b3259 100644
--- a/src/julia_internal.h
+++ b/src/julia_internal.h
@@ -1841,6 +1841,7 @@ extern JL_DLLEXPORT jl_sym_t *jl_release_sym;
 extern JL_DLLEXPORT jl_sym_t *jl_acquire_release_sym;
 extern JL_DLLEXPORT jl_sym_t *jl_sequentially_consistent_sym;
 extern JL_DLLEXPORT jl_sym_t *jl_uninferred_sym;
+extern JL_DLLEXPORT jl_sym_t *jl_worldinc_sym;
 
 JL_DLLEXPORT enum jl_memory_order jl_get_atomic_order(jl_sym_t *order, char loading, char storing);
 JL_DLLEXPORT enum jl_memory_order jl_get_atomic_order_checked(jl_sym_t *order, char loading, char storing);
diff --git a/src/toplevel.c b/src/toplevel.c
index b0163683cf87c..8ae51c5034dbb 100644
--- a/src/toplevel.c
+++ b/src/toplevel.c
@@ -225,9 +225,7 @@ static jl_value_t *jl_eval_module_expr(jl_module_t *parent_module, jl_expr_t *ex
 
     for (int i = 0; i < jl_array_nrows(exprs); i++) {
         // process toplevel form
-        ct->world_age = jl_atomic_load_acquire(&jl_world_counter);
         form = jl_expand_stmt_with_loc(jl_array_ptr_ref(exprs, i), newm, filename, lineno);
-        ct->world_age = jl_atomic_load_acquire(&jl_world_counter);
         (void)jl_toplevel_eval_flex(newm, form, 1, 1, &filename, &lineno);
     }
     ct->world_age = last_age;
@@ -607,7 +605,8 @@ int jl_is_toplevel_only_expr(jl_value_t *e) JL_NOTSAFEPOINT
          ((jl_expr_t*)e)->head == jl_const_sym ||
          ((jl_expr_t*)e)->head == jl_toplevel_sym ||
          ((jl_expr_t*)e)->head == jl_error_sym ||
-         ((jl_expr_t*)e)->head == jl_incomplete_sym);
+         ((jl_expr_t*)e)->head == jl_incomplete_sym ||
+         ((jl_expr_t*)e)->head == jl_worldinc_sym);
 }
 
 int jl_needs_lowering(jl_value_t *e) JL_NOTSAFEPOINT
@@ -864,6 +863,7 @@ JL_DLLEXPORT jl_value_t *jl_toplevel_eval_flex(jl_module_t *JL_NONNULL m, jl_val
 
     if (head == jl_module_sym) {
         jl_value_t *val = jl_eval_module_expr(m, ex);
+        ct->world_age = jl_atomic_load_acquire(&jl_world_counter);
         JL_GC_POP();
         return val;
     }
@@ -919,6 +919,9 @@ JL_DLLEXPORT jl_value_t *jl_toplevel_eval_flex(jl_module_t *JL_NONNULL m, jl_val
             jl_eval_errorf(m, *toplevel_filename, *toplevel_lineno,
                 "syntax: malformed \"using\" statement");
         }
+        if (!expanded) {
+            ct->world_age = jl_atomic_load_acquire(&jl_world_counter);
+        }
         JL_GC_POP();
         return jl_nothing;
     }
@@ -967,6 +970,12 @@ JL_DLLEXPORT jl_value_t *jl_toplevel_eval_flex(jl_module_t *JL_NONNULL m, jl_val
             jl_eval_errorf(m, *toplevel_filename, *toplevel_lineno,
                 "syntax: malformed \"import\" statement");
         }
+        if (!expanded) {
+            // To avoid having to roundtrip every `using` expression through
+            // lowering, just to add the world-age increment effect, do it
+            // manually here.
+            ct->world_age = jl_atomic_load_acquire(&jl_world_counter);
+        }
         JL_GC_POP();
         return jl_nothing;
     }
@@ -1111,8 +1120,11 @@ JL_DLLEXPORT jl_value_t *jl_toplevel_eval_in(jl_module_t *m, jl_value_t *ex)
     jl_value_t *v = NULL;
     int last_lineno = jl_lineno;
     const char *last_filename = jl_filename;
+    jl_task_t *ct = jl_current_task;
     jl_lineno = 1;
     jl_filename = "none";
+    size_t last_age = ct->world_age;
+    ct->world_age = jl_atomic_load_relaxed(&jl_world_counter);
     JL_TRY {
         v = jl_toplevel_eval(m, ex);
     }
@@ -1123,6 +1135,7 @@ JL_DLLEXPORT jl_value_t *jl_toplevel_eval_in(jl_module_t *m, jl_value_t *ex)
     }
     jl_lineno = last_lineno;
     jl_filename = last_filename;
+    ct->world_age = last_age;
     assert(v);
     return v;
 }
@@ -1170,6 +1183,7 @@ static jl_value_t *jl_parse_eval_all(jl_module_t *module, jl_value_t *text,
     int last_lineno = jl_lineno;
     const char *last_filename = jl_filename;
     size_t last_age = ct->world_age;
+    ct->world_age = jl_atomic_load_acquire(&jl_world_counter);
     int lineno = 0;
     jl_lineno = 0;
     const char *filename_str = jl_string_data(filename);
@@ -1187,7 +1201,6 @@ static jl_value_t *jl_parse_eval_all(jl_module_t *module, jl_value_t *text,
             }
             expression = jl_expand_with_loc_warn(expression, module,
                                                  jl_string_data(filename), lineno);
-            ct->world_age = jl_atomic_load_acquire(&jl_world_counter);
             result = jl_toplevel_eval_flex(module, expression, 1, 1, &filename_str, &lineno);
         }
     }
diff --git a/stdlib/Logging/test/runtests.jl b/stdlib/Logging/test/runtests.jl
index 176860fcdec63..2fedbde557078 100644
--- a/stdlib/Logging/test/runtests.jl
+++ b/stdlib/Logging/test/runtests.jl
@@ -285,7 +285,7 @@ end
             AboveMaxLevel === Logging.AboveMaxLevel
         end
         """)
-    @test m.run()
+    @test invokelatest(m.run)
 end
 
 @testset "custom log macro" begin
diff --git a/stdlib/REPL/src/REPL.jl b/stdlib/REPL/src/REPL.jl
index e3a58ec362d89..04c58c50e608f 100644
--- a/stdlib/REPL/src/REPL.jl
+++ b/stdlib/REPL/src/REPL.jl
@@ -367,6 +367,7 @@ function eval_user_input(@nospecialize(ast), backend::REPLBackend, mod::Module)
                 for xf in backend.ast_transforms
                     ast = Base.invokelatest(xf, ast)
                 end
+                toplevel_eval_with_hooks(mod, Expr(:worldinc))
                 value = toplevel_eval_with_hooks(mod, ast)
                 backend.in_eval = false
                 setglobal!(Base.MainInclude, :ans, value)
diff --git a/stdlib/REPL/test/replcompletions.jl b/stdlib/REPL/test/replcompletions.jl
index 1355f74c9bfff..b259567884486 100644
--- a/stdlib/REPL/test/replcompletions.jl
+++ b/stdlib/REPL/test/replcompletions.jl
@@ -12,150 +12,151 @@ using REPL
     end
 end
 
-let ex = quote
-    module CompletionFoo
-        using Random
-        import Test
-
-        mutable struct Test_y
-            yy
-        end
-        mutable struct Test_x
-            xx :: Test_y
-        end
-        type_test = Test_x(Test_y(1))
-        (::Test_y)() = "", ""
-        unicode_αβγ = Test_y(1)
+let ex =
+    quote
+        module CompletionFoo
+            using Random
+            import Test
+
+            mutable struct Test_y
+                yy
+            end
+            mutable struct Test_x
+                xx :: Test_y
+            end
+            type_test = Test_x(Test_y(1))
+            (::Test_y)() = "", ""
+            unicode_αβγ = Test_y(1)
 
-        Base.:(+)(x::Test_x, y::Test_y) = Test_x(Test_y(x.xx.yy + y.yy))
-        module CompletionFoo2
+            Base.:(+)(x::Test_x, y::Test_y) = Test_x(Test_y(x.xx.yy + y.yy))
+            module CompletionFoo2
 
-        end
-        const bar = 1
-        foo() = bar
-        macro foobar()
-            :()
-        end
-        macro barfoo(ex)
-            ex
-        end
-        macro error_expanding()
-            error("cannot expand @error_expanding")
-            :()
-        end
-        macro error_lowering_conditional(a)
-            if isa(a, Number)
-                return a
             end
-            throw(AssertionError("Not a Number"))
-            :()
-        end
-        macro error_throwing()
-            return quote
-                error("@error_throwing throws an error")
+            const bar = 1
+            foo() = bar
+            macro foobar()
+                :()
+            end
+            macro barfoo(ex)
+                ex
+            end
+            macro error_expanding()
+                error("cannot expand @error_expanding")
+                :()
+            end
+            macro error_lowering_conditional(a)
+                if isa(a, Number)
+                    return a
+                end
+                throw(AssertionError("Not a Number"))
+                :()
+            end
+            macro error_throwing()
+                return quote
+                    error("@error_throwing throws an error")
+                end
             end
-        end
 
-        primitive type NonStruct 8 end
-        Base.propertynames(::NonStruct) = (:a, :b, :c)
-        x = reinterpret(NonStruct, 0x00)
+            primitive type NonStruct 8 end
+            Base.propertynames(::NonStruct) = (:a, :b, :c)
+            x = reinterpret(NonStruct, 0x00)
 
-        # Support non-Dict AbstractDicts, #19441
-        mutable struct CustomDict{K, V} <: AbstractDict{K, V}
-            mydict::Dict{K, V}
-        end
+            # Support non-Dict AbstractDicts, #19441
+            mutable struct CustomDict{K, V} <: AbstractDict{K, V}
+                mydict::Dict{K, V}
+            end
 
-        Base.keys(d::CustomDict) = collect(keys(d.mydict))
-        Base.length(d::CustomDict) = length(d.mydict)
+            Base.keys(d::CustomDict) = collect(keys(d.mydict))
+            Base.length(d::CustomDict) = length(d.mydict)
 
-        # Support AbstractDict with unknown length, #55931
-        struct NoLengthDict{K,V} <: AbstractDict{K,V}
-            dict::Dict{K,V}
-            NoLengthDict{K,V}() where {K,V} = new(Dict{K,V}())
-        end
-        Base.iterate(d::NoLengthDict, s...) = iterate(d.dict, s...)
-        Base.IteratorSize(::Type{<:NoLengthDict}) = Base.SizeUnknown()
-        Base.eltype(::Type{NoLengthDict{K,V}}) where {K,V} = Pair{K,V}
-        Base.setindex!(d::NoLengthDict, v, k) = d.dict[k] = v
-
-        test(x::T, y::T) where {T<:Real} = pass
-        test(x::Real, y::Real) = pass
-        test(x::AbstractArray{T}, y) where {T<:Real} = pass
-        test(args...) = pass
-
-        test1(x::Type{Float64}) = pass
-
-        test2(x::AbstractString) = pass
-        test2(x::Char) = pass
-        test2(x::Cmd) = pass
-
-        test3(x::AbstractArray{Int}, y::Int) = pass
-        test3(x::AbstractArray{Float64}, y::Float64) = pass
-
-        test4(x::AbstractString, y::AbstractString) = pass
-        test4(x::AbstractString, y::Regex) = pass
-
-        test5(x::Array{Bool,1}) = pass
-        test5(x::BitArray{1}) = pass
-        test5(x::Float64) = pass
-        const a=x->x
-        test6()=[a, a]
-        test7() = rand(Bool) ? 1 : 1.0
-        test8() = Any[1][1]
-        test9(x::Char) = pass
-        test9(x::Char, i::Int) = pass
-
-        test10(a, x::Int...) = pass
-        test10(a::Integer, b::Integer, c) = pass
-        test10(a, y::Bool...) = pass
-        test10(a, d::Integer, z::Signed...) = pass
-        test10(s::String...) = pass
-
-        test11(a::Integer, b, c) = pass
-        test11(u, v::Integer, w) = pass
-        test11(x::Int, y::Int, z) = pass
-        test11(_, _, s::String) = pass
-
-        test!12() = pass
-
-        kwtest(; x=1, y=2, w...) = pass
-        kwtest2(a; x=1, y=2, w...) = pass
-        kwtest3(a::Number; length, len2, foobar, kwargs...) = pass
-        kwtest3(a::Real; another!kwarg, len2) = pass
-        kwtest3(a::Integer; namedarg, foobar, slurp...) = pass
-        kwtest4(a::AbstractString; _a1b, x23) = pass
-        kwtest4(a::String; _a1b, xαβγ) = pass
-        kwtest4(a::SubString; x23, _something) = pass
-        kwtest5(a::Int, b, x...; somekwarg, somekotherkwarg) = pass
-        kwtest5(a::Char, b; xyz) = pass
-
-        const named = (; len2=3)
-        const fmsoebelkv = (; len2=3)
-
-        array = [1, 1]
-        varfloat = 0.1
-
-        const tuple = (1, 2)
-
-        test_y_array=[(@__MODULE__).Test_y(rand()) for i in 1:10]
-        test_dict = Dict("abc"=>1, "abcd"=>10, :bar=>2, :bar2=>9, Base=>3,
-                         occursin=>4, `ls`=>5, 66=>7, 67=>8, ("q",3)=>11,
-                         "α"=>12, :α=>13)
-        test_customdict = CustomDict(test_dict)
-
-        macro teststr_str(s) end
-        macro tϵsτstρ_str(s) end
-        macro testcmd_cmd(s) end
-        macro tϵsτcmδ_cmd(s) end
-
-        var"complicated symbol with spaces" = 5
-
-        struct WeirdNames end
-        Base.propertynames(::WeirdNames) = (Symbol("oh no!"), Symbol("oh yes!"))
-
-        # https://github.com/JuliaLang/julia/issues/52551#issuecomment-1858543413
-        export exported_symbol
-        exported_symbol(::WeirdNames) = nothing
+            # Support AbstractDict with unknown length, #55931
+            struct NoLengthDict{K,V} <: AbstractDict{K,V}
+                dict::Dict{K,V}
+                NoLengthDict{K,V}() where {K,V} = new(Dict{K,V}())
+            end
+            Base.iterate(d::NoLengthDict, s...) = iterate(d.dict, s...)
+            Base.IteratorSize(::Type{<:NoLengthDict}) = Base.SizeUnknown()
+            Base.eltype(::Type{NoLengthDict{K,V}}) where {K,V} = Pair{K,V}
+            Base.setindex!(d::NoLengthDict, v, k) = d.dict[k] = v
+
+            test(x::T, y::T) where {T<:Real} = pass
+            test(x::Real, y::Real) = pass
+            test(x::AbstractArray{T}, y) where {T<:Real} = pass
+            test(args...) = pass
+
+            test1(x::Type{Float64}) = pass
+
+            test2(x::AbstractString) = pass
+            test2(x::Char) = pass
+            test2(x::Cmd) = pass
+
+            test3(x::AbstractArray{Int}, y::Int) = pass
+            test3(x::AbstractArray{Float64}, y::Float64) = pass
+
+            test4(x::AbstractString, y::AbstractString) = pass
+            test4(x::AbstractString, y::Regex) = pass
+
+            test5(x::Array{Bool,1}) = pass
+            test5(x::BitArray{1}) = pass
+            test5(x::Float64) = pass
+            const a=x->x
+            test6()=[a, a]
+            test7() = rand(Bool) ? 1 : 1.0
+            test8() = Any[1][1]
+            test9(x::Char) = pass
+            test9(x::Char, i::Int) = pass
+
+            test10(a, x::Int...) = pass
+            test10(a::Integer, b::Integer, c) = pass
+            test10(a, y::Bool...) = pass
+            test10(a, d::Integer, z::Signed...) = pass
+            test10(s::String...) = pass
+
+            test11(a::Integer, b, c) = pass
+            test11(u, v::Integer, w) = pass
+            test11(x::Int, y::Int, z) = pass
+            test11(_, _, s::String) = pass
+
+            test!12() = pass
+
+            kwtest(; x=1, y=2, w...) = pass
+            kwtest2(a; x=1, y=2, w...) = pass
+            kwtest3(a::Number; length, len2, foobar, kwargs...) = pass
+            kwtest3(a::Real; another!kwarg, len2) = pass
+            kwtest3(a::Integer; namedarg, foobar, slurp...) = pass
+            kwtest4(a::AbstractString; _a1b, x23) = pass
+            kwtest4(a::String; _a1b, xαβγ) = pass
+            kwtest4(a::SubString; x23, _something) = pass
+            kwtest5(a::Int, b, x...; somekwarg, somekotherkwarg) = pass
+            kwtest5(a::Char, b; xyz) = pass
+
+            const named = (; len2=3)
+            const fmsoebelkv = (; len2=3)
+
+            array = [1, 1]
+            varfloat = 0.1
+
+            const tuple = (1, 2)
+
+            test_y_array=[(@__MODULE__).Test_y(rand()) for i in 1:10]
+            test_dict = Dict("abc"=>1, "abcd"=>10, :bar=>2, :bar2=>9, Base=>3,
+                            occursin=>4, `ls`=>5, 66=>7, 67=>8, ("q",3)=>11,
+                            "α"=>12, :α=>13)
+            test_customdict = CustomDict(test_dict)
+
+            macro teststr_str(s) end
+            macro tϵsτstρ_str(s) end
+            macro testcmd_cmd(s) end
+            macro tϵsτcmδ_cmd(s) end
+
+            var"complicated symbol with spaces" = 5
+
+            struct WeirdNames end
+            Base.propertynames(::WeirdNames) = (Symbol("oh no!"), Symbol("oh yes!"))
+
+            # https://github.com/JuliaLang/julia/issues/52551#issuecomment-1858543413
+            export exported_symbol
+            exported_symbol(::WeirdNames) = nothing
 
         end # module CompletionFoo
         test_repl_comp_dict = CompletionFoo.test_dict
diff --git a/stdlib/Serialization/test/runtests.jl b/stdlib/Serialization/test/runtests.jl
index a7d5023e1ec51..c2a14b68be2ed 100644
--- a/stdlib/Serialization/test/runtests.jl
+++ b/stdlib/Serialization/test/runtests.jl
@@ -595,7 +595,7 @@ let f_data
         f_data = "N0pMBwAAAAA0MxMAAAAAAAAAAAEFIyM1IzYiAAAAABBYH04BBE1haW6bRCIAAAAAIgAAAABNTEy+AQIjNRUAI78jAQAAAAAAAAAfTgEETWFpbkQBAiM1AQdSRVBMWzJdvxBTH04BBE1haW6bRAMAAAAzLAAARkYiAAAAAE7BTBsVRsEWA1YkH04BBE1haW5EAQEqwCXAFgNWJB9OAQRNYWluRJ0ovyXBFgFVKMAVAAbBAQAAAAEAAAABAAAATsEVRr80EAEMTGluZUluZm9Ob2RlH04BBE1haW6bRB9OAQRNYWluRAECIzUBB1JFUExbMl2/vhW+FcEAAAAVRsGifX5MTExMTsEp"
     end
     f = deserialize(IOBuffer(base64decode(f_data)))
-    @test f(10,3) == 23
+    @test invokelatest(f, 10,3) == 23
 end
 
 # issue #33466, IdDict
diff --git a/stdlib/Test/src/Test.jl b/stdlib/Test/src/Test.jl
index cf906591b9962..e8c7d49d076aa 100644
--- a/stdlib/Test/src/Test.jl
+++ b/stdlib/Test/src/Test.jl
@@ -890,10 +890,17 @@ macro test_warn(msg, expr)
     quote
         let fname = tempname()
             try
-                ret = open(fname, "w") do f
-                    redirect_stderr(f) do
-                        $(esc(expr))
-                    end
+                f = open(fname, "w")
+                stdold = stderr
+                redirect_stderr(f)
+                ret = try
+                    # We deliberately don't use the thunk versions of open/redirect
+                    # to ensure that adding the macro does not change the toplevel-ness
+                    # of the resulting expression.
+                    $(esc(expr))
+                finally
+                    redirect_stderr(stdold)
+                    close(f)
                 end
                 @test contains_warn(read(fname, String), $(esc(msg)))
                 ret
@@ -922,10 +929,14 @@ macro test_nowarn(expr)
         # here.
         let fname = tempname()
             try
-                ret = open(fname, "w") do f
-                    redirect_stderr(f) do
-                        $(esc(expr))
-                    end
+                f = open(fname, "w")
+                stdold = stderr
+                redirect_stderr(f)
+                ret = try
+                    $(esc(expr))
+                finally
+                    redirect_stderr(stdold)
+                    close(f)
                 end
                 stderr_content = read(fname, String)
                 print(stderr, stderr_content) # this is helpful for debugging
diff --git a/test/backtrace.jl b/test/backtrace.jl
index ee04a46b17304..0e3d2ba570cb2 100644
--- a/test/backtrace.jl
+++ b/test/backtrace.jl
@@ -24,6 +24,7 @@ eval(Expr(:function, Expr(:call, :test_inline_1),
                                     Expr(:call, :throw, "foo"),
                                     Expr(:meta, :pop_loc),
                                     Expr(:line, 99)))))
+@Core.worldinc
 
 @test functionloc(test_inline_1) == ("backtrace.jl", 99)
 try
@@ -49,6 +50,7 @@ eval(Expr(:function, Expr(:call, :test_inline_2),
                                     Expr(:call, :throw, "foo"),
                                     Expr(:meta, :pop_loc),
                                     Expr(:line, 99)))))
+@Core.worldinc
 
 @test functionloc(test_inline_2) == ("backtrace.jl", 81)
 try
diff --git a/test/ccall.jl b/test/ccall.jl
index b10504de21abc..4872069ecdf31 100644
--- a/test/ccall.jl
+++ b/test/ccall.jl
@@ -70,8 +70,10 @@ function gen_ccall_echo(x, T, U, ret=nothing)
         func_ex = :($ret($func_ex))
     end
     @gensym func_name
-    @eval @noinline $func_name(x) = $func_ex
-    :($func_name($(esc(x))))
+    quote
+        @noinline $(esc(func_name))(x) = $func_ex
+        $(esc(func_name))($(esc(x)))
+    end
 end
 
 macro ccall_echo_func(x, T, U)
diff --git a/test/core.jl b/test/core.jl
index 1b36db466ce19..e789cfc501e41 100644
--- a/test/core.jl
+++ b/test/core.jl
@@ -2621,7 +2621,9 @@ end
 # issue #8338
 let ex = Expr(:(=), :(f8338(x;y=4)), :(x*y))
     eval(ex)
-    @test f8338(2) == 8
+    invokelatest() do
+        @test f8338(2) == 8
+    end
 end
 
 # call overloading (#2403)
@@ -8332,3 +8334,13 @@ let s = mktemp() do path, io
     end
     @test strip(s) == "xxx = 42"
 end
+
+# `module` has an implicit world-age increment
+let foo = eval(Expr(:toplevel, :(module BarModuleInc; struct FooModuleInc; end; end), :(BarModuleInc.FooModuleInc())))
+    @Core.worldinc
+    @test foo == BarModuleInc.FooModuleInc()
+end
+
+eval(:(module BarModuleInc; module BazModuleInc; struct FooModuleInc; end; end; const foo = BazModuleInc.FooModuleInc(); end))
+@Core.worldinc
+@test BarModuleInc.foo == BarModuleInc.BazModuleInc.FooModuleInc()
diff --git a/test/deprecation_exec.jl b/test/deprecation_exec.jl
index 61ffcc2a59ac6..92fb3d98cb015 100644
--- a/test/deprecation_exec.jl
+++ b/test/deprecation_exec.jl
@@ -68,6 +68,7 @@ begin # @deprecate
     ex = :(module M22845; import ..DeprecationTests: bar;
                           bar(x::Number) = x + 3; end)
     @test_warn "importing deprecated binding" eval(ex)
+    @Core.worldinc
     @test @test_nowarn(DeprecationTests.bar(4)) == 7
 
     @test @test_warn "`f1` is deprecated, use `f` instead." f1()
diff --git a/test/error.jl b/test/error.jl
index 8657c70720779..550d7ae634e12 100644
--- a/test/error.jl
+++ b/test/error.jl
@@ -93,6 +93,7 @@ end
 @testset "MethodError for methods without line numbers" begin
     try
         eval(Expr(:function, :(f44319()), 0))
+        @Core.worldinc
         f44319(1)
     catch e
         s = sprint(showerror, e)
diff --git a/test/llvmcall.jl b/test/llvmcall.jl
index c83ac05b1ec48..cb87ae3386597 100644
--- a/test/llvmcall.jl
+++ b/test/llvmcall.jl
@@ -158,6 +158,7 @@ module ObjLoadTest
     end
     @test_throws(ErrorException("@ccallable was already defined for this method name"),
                  @eval @ccallable Cvoid jl_the_callback(not_the_method::Int) = "other")
+    @Core.worldinc
     # Make sure everything up until here gets compiled
     @test jl_the_callback() === nothing
     @test jl_the_callback(1) == "other"
diff --git a/test/rebinding.jl b/test/rebinding.jl
index c93c34be7a75c..0396bbb1fb424 100644
--- a/test/rebinding.jl
+++ b/test/rebinding.jl
@@ -15,6 +15,7 @@ module Rebinding
     @test Base.binding_kind(@__MODULE__, :Foo) == Base.BINDING_KIND_CONST
     @test !contains(repr(x), "@world")
     Base.delete_binding(@__MODULE__, :Foo)
+    @Core.worldinc
 
     @test Base.binding_kind(@__MODULE__, :Foo) == Base.BINDING_KIND_GUARD
     @test contains(repr(x), "@world")
diff --git a/test/reflection.jl b/test/reflection.jl
index 8c701acb9c09d..0c2c330a59873 100644
--- a/test/reflection.jl
+++ b/test/reflection.jl
@@ -777,6 +777,7 @@ faz1(x) = foo1(x)
 @test faz1(1.0) == 1
 m = first(methods(bar1, Tuple{Int}))
 Base.delete_method(m)
+@Core.worldinc
 @test bar1(1) == 1
 @test bar1(1.0) == 1
 @test foo1(1) == 1
@@ -793,6 +794,7 @@ faz2(x) = foo2(x)
 @test foo2(1.0) == 1
 m = first(methods(bar2, Tuple{Int}))
 Base.delete_method(m)
+@Core.worldinc
 @test bar2(1.0) == 1
 @test bar2(1) == 1
 @test foo2(1) == 1
@@ -809,6 +811,7 @@ faz3(x) = foo3(x)
 @test bar3(1.0) == 1
 m = first(methods(bar3, Tuple{Int}))
 Base.delete_method(m)
+@Core.worldinc
 @test bar3(1) == 1
 @test bar3(1.0) == 1
 @test foo3(1) == 1
@@ -823,6 +826,7 @@ foo4(x) = bar4(x)
 faz4(x) = foo4(x)
 m = first(methods(bar4, Tuple{Int}))
 Base.delete_method(m)
+@Core.worldinc
 @test bar4(1) == 1
 @test bar4(1.0) == 1
 @test foo4(1) == 1
@@ -846,12 +850,15 @@ log = Ref{String}()
 @test f48802!(log, 1) == 2
 @test log[] == "default"
 addmethod_48802()
+@Core.worldinc
 @test f48802!(log, 1) == 2
 @test log[] == "specialized"
 Base.delete_method(which(f48802!, Tuple{Any, Int}))
+@Core.worldinc
 @test f48802!(log, 1) == 2
 @test log[] == "default"
 addmethod_48802()
+@Core.worldinc
 @test f48802!(log, 1) == 2
 @test log[] == "specialized"
 
@@ -862,6 +869,7 @@ fookw(y::Int) = 2
 @test fookw(1) == 2
 m = collect(methods(fookw))[2]
 Base.delete_method(m)
+@Core.worldinc
 @test fookw(1) == 2
 @test_throws MethodError fookw("string")
 
@@ -873,12 +881,14 @@ end
 @test foomany(Int32(5), "hello", 3.2) == "hello"
 m = first(methods(foomany, Tuple{Int32, String, Float64}))
 Base.delete_method(m)
+@Core.worldinc
 @test_throws MethodError foomany(Int32(5), "hello", 3.2)
 
 struct EmptyType end
 Base.convert(::Type{EmptyType}, x::Integer) = EmptyType()
 m = first(methods(convert, Tuple{Type{EmptyType}, Integer}))
 Base.delete_method(m)
+@Core.worldinc
 @test_throws MethodError convert(EmptyType, 1)
 
 # parametric methods
@@ -886,6 +896,7 @@ parametric(A::Array{T,N}, i::Vararg{Int,N}) where {T,N} = N
 @test parametric(rand(2,2), 1, 1) == 2
 m = first(methods(parametric))
 Base.delete_method(m)
+@Core.worldinc
 @test_throws MethodError parametric(rand(2,2), 1, 1)
 
 # Deletion and ambiguity detection
@@ -893,10 +904,12 @@ foo(::Int, ::Int) = 1
 foo(::Real, ::Int) = 2
 foo(::Int, ::Real) = 3
 Base.delete_method(first(methods(foo)))
+@Core.worldinc
 @test_throws MethodError foo(1, 1)
 foo(::Int, ::Int) = 1
 foo(1, 1)
 Base.delete_method(first(methods(foo)))
+@Core.worldinc
 @test_throws MethodError foo(1, 1)
 
 # multiple deletions and ambiguities
@@ -918,6 +931,7 @@ uambig(::Union{Float64,Nothing}) = 2
 @test_throws MethodError uambig(nothing)
 m = which(uambig, Tuple{Int})
 Base.delete_method(m)
+@Core.worldinc
 @test_throws MethodError uambig(1)
 @test uambig(1.0) == 2
 @test uambig(nothing) == 2
diff --git a/test/syntax.jl b/test/syntax.jl
index c19721b5c54b3..9309d42f5bceb 100644
--- a/test/syntax.jl
+++ b/test/syntax.jl
@@ -553,7 +553,14 @@ for (str, tag) in Dict("" => :none, "\"" => :string, "#=" => :comment, "'" => :c
 end
 
 # meta nodes for optional positional arguments
-let src = Meta.lower(Main, :(@inline f(p::Int=2) = 3)).args[1].code[end-2].args[3]
+let code = Meta.lower(Main, :(@inline f(p::Int=2) = 3)).args[1].code
+    local src
+    for i = length(code):-1:1
+        if Meta.isexpr(code[i], :method)
+            src = code[i].args[3]
+            break
+        end
+    end
     @test Core.Compiler.is_declared_inline(src)
 end
 
@@ -578,6 +585,7 @@ let thismodule = @__MODULE__,
     @test isa(ex, Expr)
     @test !isdefined(M16096, :foo16096)
     local_foo16096 = Core.eval(@__MODULE__, ex)
+    Core.@worldinc
     @test local_foo16096(2.0) == 1
     @test !@isdefined foo16096
     @test !@isdefined it
@@ -3102,6 +3110,7 @@ end
     ex = Expr(:block)
     ex.args = fill!(Vector{Any}(undef, 700000), 1)
     f = eval(Expr(:function, :(), ex))
+    @Core.worldinc
     @test f() == 1
     ex = Expr(:vcat)
     ex.args = fill!(Vector{Any}(undef, 600000), 1)