Summary:
Patch from a series of patches to rename EAPI symbols to specific
library DSOs.
= The Rationale =
This patch is from a series of patches to rename EAPI symbols to
specific library DSOs.
EAPI was designed to be able to pass
`__attribute__ ((visibility ("default")))` for symbols with
GCC, which would mean that even if -fvisibility=hidden was used
when compiling the library, the needed symbols would get exported.
MSVC __almost__ works like GCC (or mingw) in which you can
declare everything as export and it will just work (slower, but
it will work). But there's a caveat: global variables will not
work the same way for MSVC, but works for mingw and GCC.
For global variables (as opposed to functions), MSVC requires
correct DSO visibility for MSVC: instead of declaring a symbol as
export for everything, you need to declare it as import when
importing from another DSO and export when defining it locally.
With current EAPI definitions, we get the following example
working in mingw and MSVC (observe it doesn't define any global
variables as exported symbols).
Example 1:
dll1:
```
EAPI void foo(void);
EAPI void bar()
{
foo();
}
```
dll2:
```
EAPI void foo()
{
printf ("foo\n");
}
```
This works fine with API defined as __declspec(dllexport) in both
cases and for gcc defining as
`__atttribute__((visibility("default")))`.
However, the following:
Example 2:
dll1:
```
EAPI extern int foo;
EAPI void foobar(void);
EAPI void bar()
{
foo = 5;
foobar();
}
```
dll2:
```
EAPI int foo = 0;
EAPI void foobar()
{
printf ("foo %d\n", foo);
}
```
This will work on mingw but will not work for MSVC. And that's why
LIBAPI is the only solution that works for MSVC.
Co-authored-by: João Paulo Taylor Ienczak Zanette <jpaulotiz@gmail.com>
Co-authored-by: Lucas Cavalcante de Sousa <lucks.sousa@gmail.com>
Co-authored-by: Ricardo Campos <ricardo.campos@expertise.dev>
Reviewers: jptiz, lucas, vtorri, woohyun
Reviewed By: jptiz, lucas, vtorri
Subscribers: cedric, #reviewers, #committers
Tags: #efl
Differential Revision: https://phab.enlightenment.org/D12203
I just ran my script (email to follow) to migrate all of the EFL
automatically. This commit is *only* the automatic conversion, so it can
be easily reverted and re-run.
From now on, constructors should return a value, usually the object
being worked on, or NULL (if the constructor failed). This can also
be used for implementing singletons, by just always returning the same
object from the constructor.
This is one of the final steps towards stabilizing Eo.
@feature
Overloaded address-of operator for C++ Eolian wrappers for implicit converting
to any ancestor pointer type when getting the object memory address.
Added new grammars to aid the creation of the pointer wrappers
responsible of doing the implicit conversions.
Added a unit test which checks the address-of overload for arbitrary classes.
Added new .eo files to be used in it.
Felipe Magno de Almeida
Tom Hacohen
Vincent Torri
Vitor Sousa