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Re: [patch] Re: Regression: field type preservation: 7.0 -> 7.0.1+HEAD
> gdb/
> 2010-01-02 Jan Kratochvil <jan.kratochvil@redhat.com>
>
> * value.c (value_primitive_field): Remove one check_typedef call.
> Move bitpos and container_bitsize initialization after
> allocate_value_lazy. New comment before accessing TYPE_LENGTH.
Interesting. This patch allowed me to figure out why the initial patch
sent by Vladimir was in fact working when it looks like it could not
possibly work :).
Personally, I'm not a big fan of the approach you took in this case.
You rely on a side-effect of the various allocate_* routines, but
this is only because these routines call check_typedef. In particular,
there is something interesting in allocate_value_lazy. A variable is
declared...
struct type *atype = check_typedef (type);
... but then never used. There is no available info as to why this is,
as this is here since day 1 of the public CVS repo, but it's now clear
to me that this helps fixing that length - a type length that does not
appear to be used at all in the rest of the routine!
In my opinion, I agree with Daniel's comment that it is unusual to
call check_typedef without storing the function result. But this
seems to be less awkward than relying on an undocumented side-effect
of a function that uses an undocumented side-effect of a check_typedef,
especially since the function in question does not really need that
side-effect to be applied at the time the function is called!
So, my proposal, if the other maintainers agree, is to document
the side-effect of check_typedef (sets the typedef TYPE_LENGTH)
as this appears to be a fully-intended behavior, and then do:
> - type = check_typedef (type);
> + /* Call check_typedef on our type to make sure that, if TYPE
> + is a TYPE_CODE_TYPEDEF, its length is set to the length
> + of the target type instead of zero. However, we do not
> + replace the typedef type by the target type, because we want
> + to keep the typedef in order to be able to print the type
> + description correctly. */
> + check_typedef (type);
> gdb/testsuite/
> 2010-01-02 Jan Kratochvil <jan.kratochvil@redhat.com>
>
> * gdb.mi/var-cmd.c (do_bitfield_tests): Change "V.sharable" type to
> "uint_for_mi_testing".
This part is OK.
--
Joel