fix serializer compat with CodeInfos from v1.11

src/method.c

@@ -957,6 +957,9 @@ JL_DLLEXPORT void jl_method_set_source(jl_method_t *m, jl_code_info_t *src)
     }
     src = jl_copy_code_info(src);
     src->isva = m->isva; // TODO: It would be nice to reverse this
+    // If nargs hasn't been set yet, do it now. This can happen if an old CodeInfo is deserialized.
+    if (src->nargs == 0)
+        src->nargs = m->nargs;
     assert(m->nargs == src->nargs);
     src->code = copy;
     jl_gc_wb(src, copy);

stdlib/Serialization/src/Serialization.jl

@@ -23,11 +23,25 @@ mutable struct Serializer{I<:IO} <: AbstractSerializer
     pending_refs::Vector{Int}
     known_object_data::Dict{UInt64,Any}
     version::Int
-    Serializer{I}(io::I) where I<:IO = new(io, 0, IdDict(), Int[], Dict{UInt64,Any}(), ser_version)
+    current_module::Union{Nothing,Module}
+    Serializer{I}(io::I) where I<:IO = new(io, 0, IdDict(), Int[], Dict{UInt64,Any}(), ser_version, nothing)
 end
 
 Serializer(io::IO) = Serializer{typeof(io)}(io)
 
+macro withmodule(s, m, code)
+    s, m, code = esc(s), esc(m), esc(code)
+    quote
+        _prev = ($s).current_module
+        ($s).current_module = $m
+        try
+            $code
+        finally
+            ($s).current_module = _prev
+        end
+    end
+end
+
 ## serializing values ##
 
 const n_int_literals = 33
@@ -1064,7 +1078,10 @@ function deserialize(s::AbstractSerializer, ::Type{Method})
     nospecializeinfer = false
     constprop = 0x00
     purity = 0x0000
-    template_or_is_opaque = deserialize(s)
+    local template_or_is_opaque, template
+    @withmodule s mod begin
+        template_or_is_opaque = deserialize(s)
+    end
     if isa(template_or_is_opaque, Bool)
         is_for_opaque_closure = template_or_is_opaque
         if format_version(s) >= 24
@@ -1078,7 +1095,9 @@ function deserialize(s::AbstractSerializer, ::Type{Method})
         elseif format_version(s) >= 17
             purity = UInt16(deserialize(s)::UInt8)
         end
-        template = deserialize(s)
+        @withmodule s mod begin
+            template = deserialize(s)
+        end
     else
         template = template_or_is_opaque
     end
@@ -1182,6 +1201,22 @@ function deserialize(s::AbstractSerializer, ::Type{PhiNode})
     return PhiNode(edges, values)
 end
 
+# v1.12 disallows bare symbols in IR, but older CodeInfos might still have them
+function symbol_to_globalref(@nospecialize(x), m::Module)
+    mapper(@nospecialize(x)) = symbol_to_globalref(x, m)
+    if x isa Symbol
+        return GlobalRef(m, x)
+    elseif x isa Expr
+        return Expr(x.head, map(mapper, x.args)...)
+    elseif x isa ReturnNode
+        return ReturnNode(mapper(x.val))
+    elseif x isa GotoIfNot
+        return GotoIfNot(mapper(x.cond), x.dest)
+    else
+        return x
+    end
+end
+
 function deserialize(s::AbstractSerializer, ::Type{CodeInfo})
     ci = ccall(:jl_new_code_info_uninit, Ref{CodeInfo}, ())
     deserialize_cycle(s, ci)
@@ -1200,6 +1235,9 @@ function deserialize(s::AbstractSerializer, ::Type{CodeInfo})
             end
         end
     end
+    if s.current_module !== nothing
+        map!(x->symbol_to_globalref(x, s.current_module), code)
+    end
     _x = deserialize(s)
     have_debuginfo = _x isa Core.DebugInfo
     if have_debuginfo
@@ -1248,6 +1286,9 @@ function deserialize(s::AbstractSerializer, ::Type{CodeInfo})
         ci.slottypes = deserialize(s)
         ci.rettype = deserialize(s)
         ci.parent = deserialize(s)
+        if format_version(s) < 29 && ci.parent isa MethodInstance && ci.parent.def isa Method
+            ci.nargs = ci.parent.def.nargs
+        end
         world_or_edges = deserialize(s)
         pre_13 = isa(world_or_edges, Union{UInt, Int})
         if pre_13
@@ -1258,7 +1299,7 @@ function deserialize(s::AbstractSerializer, ::Type{CodeInfo})
             ci.min_world = deserialize(s)::UInt
             ci.max_world = deserialize(s)::UInt
         end
-        if format_version(s) >= 26
+        if format_version(s) >= 29
             ci.method_for_inference_limit_heuristics = deserialize(s)
         end
     end

stdlib/Serialization/test/runtests.jl

@@ -661,3 +661,14 @@ end
     @test_broken isempty(undoc)
     @test undoc == [:AbstractSerializer, :Serializer]
 end
+
+# test method definitions from v1.11
+if Int === Int64
+    let f_data = "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"
+        @eval Main function f111_to_112 end
+        s = Serializer(IOBuffer(base64decode(f_data)))
+        s.current_module = Main
+        Core.eval(Main, deserialize(s))
+        @test @invokelatest(Main.f111_to_112(16)) == 256
+    end
+end