[Bug d/103040] [12 Regression] gdc.dg/torture/pr101273.d FAILs

[Jan Hubicka]

> See above comments from Iain, even if that pre-initialization is removed it is
> still miscompiled.  And, the testcase fails not because of the padding bits not
> being zero, but because the address of self stored into one of the fields isn't
> there or modref thinks it can't be changed or set to that.  But for
> corresponding C++ it handles it ok.
Perhaps TREE_ADDRESSABLE on the type which is being used to test whether
return slot pointer may escape.