Merge pull request #44641 from JuliaLang/jn/44614

types: fix layout issues for Tuple

Author: vtjnash

src/datatype.c

@@ -1788,9 +1788,9 @@ JL_DLLEXPORT int jl_field_isdefined(jl_value_t *v, size_t i) JL_NOTSAFEPOINT
     return fval != NULL ? 1 : 0;
 }
 
-JL_DLLEXPORT size_t jl_get_field_offset(jl_datatype_t *ty, int field) JL_NOTSAFEPOINT
+JL_DLLEXPORT size_t jl_get_field_offset(jl_datatype_t *ty, int field)
 {
-    if (ty->layout == NULL || field > jl_datatype_nfields(ty) || field < 1)
+    if (!jl_struct_try_layout(ty) || field > jl_datatype_nfields(ty) || field < 1)
         jl_bounds_error_int((jl_value_t*)ty, field);
     return jl_field_offset(ty, field - 1);
 }

src/jl_exported_funcs.inc

@@ -214,7 +214,6 @@
     XX(jl_get_excstack) \
     XX(jl_get_fenv_consts) \
     XX(jl_get_field) \
-    XX(jl_get_field_offset) \
     XX(jl_get_global) \
     XX(jl_get_image_file) \
     XX(jl_get_JIT) \

src/jltypes.c

@@ -63,6 +63,12 @@ static int layout_uses_free_typevars(jl_value_t *v, jl_typeenv_t *env)
             return 0;
         if (dt->name == jl_namedtuple_typename)
             return layout_uses_free_typevars(jl_tparam0(dt), env) || layout_uses_free_typevars(jl_tparam1(dt), env);
+        if (dt->name == jl_tuple_typename)
+            // conservative, since we don't want to inline an abstract tuple,
+            // and we currently declare !has_fixed_layout for these, but that
+            // means we also won't be able to inline a tuple which is concrete
+            // except for the use of free type-vars
+            return 1;
         jl_svec_t *types = jl_get_fieldtypes(dt);
         size_t i, l = jl_svec_len(types);
         for (i = 0; i < l; i++) {
@@ -227,8 +233,10 @@ int jl_has_fixed_layout(jl_datatype_t *dt)
         return 1;
     if (dt->name->abstract)
         return 0;
-    if (jl_is_tuple_type(dt) || jl_is_namedtuple_type(dt))
-        return 0; // TODO: relax more?
+    if (dt->name == jl_namedtuple_typename)
+        return !layout_uses_free_typevars(jl_tparam0(dt), NULL) && !layout_uses_free_typevars(jl_tparam1(dt), NULL);
+    if (dt->name == jl_tuple_typename)
+        return 0;
     jl_svec_t *types = jl_get_fieldtypes(dt);
     size_t i, l = jl_svec_len(types);
     for (i = 0; i < l; i++) {

test/core.jl

@@ -7360,6 +7360,29 @@ struct A43411{S, T}
 end
 @test isbitstype(A43411{(:a,), Tuple{Int}})
 
+# issue #44614
+struct T44614_1{T}
+    m::T
+end
+struct T44614_2{L}
+    tuple::NTuple{3, Int64}
+    T44614_2{L}(t::NTuple{3, Int64}) where {L} = new{sum(t)}(t)
+end
+struct T44614_3{L, N}
+    a::Tuple{T44614_2{L}}
+    param::NTuple{N, T44614_1}
+    T44614_3(a::Tuple{T44614_2{L}}, pars::NTuple{N, T44614_1}) where {L, N} = new{L, N}(a, pars)
+end
+@test sizeof((T44614_2{L} where L).body) == 24
+let T = T44614_3{L,2} where L
+    # these values are computable, but we currently don't know how to compute them properly
+    ex = ErrorException("Argument is an incomplete T44614_3 type and does not have a definite size.")
+    @test_throws ex sizeof(T.body)
+    @test_throws ex sizeof(T)
+    @test_throws BoundsError fieldoffset(T.body, 2)
+    @test fieldoffset(T{1}, 2) == 24
+end
+
 # Issue #34206/34207
 function mre34206(a, n)
     va = view(a, :)