If we need to initialize a holder around an unowned instance, and the
holder type is non-copyable (i.e. a unique_ptr), we currently construct
the holder type around the value pointer, but then never actually
destruct the holder: the holder destructor is called only for the
instance that actually has `inst->owned = true` set.
This seems no pointer, however, in creating such a holder around an
unowned instance: we never actually intend to use anything that the
unique_ptr gives us: and, in fact, do not want the unique_ptr (because
if it ever actually got destroyed, it would cause destruction of the
wrapped pointer, despite the fact that that wrapped pointer isn't
owned).
This commit changes the logic to only create a unique_ptr holder if we
actually own the instance, and to destruct via the constructed holder
whenever we have a constructed holder--which will now only be the case
for owned-unique-holder or shared-holder types.
Other changes include:
* Added test for non-movable holder constructor/destructor counts
The three alive assertions now pass, before #478 they fail with counts
of 2/2/1 respectively, because of the unique_ptr that we don't want and
don't destroy (because we don't *want* its destructor to run).
* Return cstats reference; fix ConstructStats doc
Small cleanup to the #478 test code, and fix to the ConstructStats
documentation (the static method definition should use `reference` not
`reference_internal`).
* Rename inst->constructed to inst->holder_constructed
This makes it clearer exactly what it's referring to.
There are now more places than just descr.h that make use of these.
The new macro isn't quite the same: the old one only tested for a
couple features, while the new one checks for the __cplusplus version
(but doesn't even try to enable C++14 for MSVC/ICC).
g++ 7 adds <optional>, but including it in C++14 mode isn't allowed
(just as including <experimental/optional> isn't allowed in C++11 mode).
(This wasn't triggered in g++-6 because it doesn't provide <optional>
yet.)
* Add debugging info about so size to build output
This adds a small python script to tools that captures before-and-after
.so sizes between builds and outputs this in the build output via a
string such as:
------ pybind11_tests.cpython-35m-x86_64-linux-gnu.so file size: 924696 (decrease of 73680 bytes = 7.38%)
------ pybind11_tests.cpython-35m-x86_64-linux-gnu.so file size: 998376 (increase of 73680 bytes = 7.97%)
------ pybind11_tests.cpython-35m-x86_64-linux-gnu.so file size: 998376 (no change)
Or, if there was no .so during the build, just the .so size by itself:
------ pybind11_tests.cpython-35m-x86_64-linux-gnu.so file size: 998376
This allows you to, for example, build, checkout a different branch,
rebuild, and easily see exactly the change in the pybind11_tests.so
size.
It also allows looking at the travis and appveyor build logs to get an
idea of .so/.dll sizes across different build systems.
* Minor libsize.py script changes
- Use RAII open
- Remove unused libsize=-1
- Report change as [+-]xyz bytes = [+-]a.bc%
* Add type caster for std::experimental::optional
* Add tests for std::experimental::optional
* Support both <optional> / <experimental/optional>
* Mention std{::experimental,}::optional in the docs
* Make reference(_internal) the default return value policy for properties
Before this, all `def_property*` functions used `automatic` as their
default return value policy. This commit makes it so that:
* Non-static properties use `reference_interal` by default, thus
matching `def_readonly` and `def_readwrite`.
* Static properties use `reference` by default, thus matching
`def_readonly_static` and `def_readwrite_static`.
In case `cpp_function` is passed to any `def_property*`, its policy will
be used instead of any defaults. User-defined arguments in `extras`
still have top priority and will override both the default policies and
the ones from `cpp_function`.
Resolves#436.
* Almost always use return_value_policy::move for rvalues
For functions which return rvalues or rvalue references, the only viable
return value policies are `copy` and `move`. `reference(_internal)` and
`take_ownership` would take the address of a temporary which is always
an error.
This commit prevents possible user errors by overriding the bad rvalue
policies with `move`. Besides `move`, only `copy` is allowed, and only
if it's explicitly selected by the user.
This is also a necessary safety feature to support the new default
return value policies for properties: `reference(_internal)`.
The current integer caster was unnecessarily strict and rejected
various kinds of NumPy integer types when calling C++ functions
expecting normal integers. This relaxes the current behavior.
Currently pybind11 doesn't check when you define a new object (e.g. a
class, function, or exception) that overwrites an existing one. If the
thing being overwritten is a class, this leads to a segfault (because
pybind still thinks the type is defined, even though Python no longer
has the type). In other cases this is harmless (e.g. replacing a
function with an exception), but even in that case it's most likely a
bug.
This code doesn't prevent you from actively doing something harmful,
like deliberately overwriting a previous definition, but detects
overwriting with a run-time error if it occurs in the standard
class/function/exception/def registration interfaces.
All of the additions are in non-template code; the result is actually a
tiny decrease in .so size compared to master without the new test code
(977304 to 977272 bytes), and about 4K higher with the new tests.
type_caster_generic::cast(): The values of
wrapper->value
wrapper->owned
are incorrect in the case that a return value policy of 'copy' is
requested but there is no copy-constructor. (Similarly 'move'.) In
particular, if the source object is a static instance, the destructor of
the 'object' 'inst' leads to class_::dealloc() which incorrectly
attempts to 'delete' the static instance.
This commit re-arranges the code to be clearer as to what the values of
'value' and 'owned' should be in the various cases. Behaviour is
different to previous code only in two situations:
policy = copy but no copy-ctor: Old code leaves 'value = src, owned =
true', which leads to trouble. New code leaves 'value = nullptr, owned
= false', which is correct.
policy = move but no move- or copy-ctor: old code leaves 'value = src,
owned = true', which leads to trouble. New code leaves 'value =
nullptr, owned = false', which is correct.
With this there is no more need for manual user declarations like
`PYBIND11_DECLARE_HOLDER_TYPE(T, std::shared_ptr<T>)`. Existing ones
will still compile without error -- they will just be ignored silently.
Resolves#446.
