On Wed, Sep 22, 2021 at 12:56 PM Johannes Sixt <j6t@xxxxxxxx> wrote:
>
> Here, GCC warns about every use of the INIT_PROC_ADDR macro, for example:
>
> In file included from compat/mingw.c:8:
> compat/mingw.c: In function 'mingw_strftime':
> compat/win32/lazyload.h:38:12: warning: assignment to
> 'size_t (*)(char *, size_t, const char *, const struct tm *)'
> {aka 'long long unsigned int (*)(char *, long long unsigned int,
> const char *, const struct tm *)'} from incompatible pointer type
> 'FARPROC' {aka 'long long int (*)()'} [-Wincompatible-pointer-types]
> 38 | (function = get_proc_addr(&proc_addr_##function))
> | ^
> compat/mingw.c:1014:6: note: in expansion of macro 'INIT_PROC_ADDR'
> 1014 | if (INIT_PROC_ADDR(strftime))
> | ^~~~~~~~~~~~~~
did you have CFLAGS adding -Wincompatible-pointer-types explicitly?
This is the reason why the code that got merged to master had -Wno
for this case.
> (message wrapper for convenience). Insert a cast to keep the compiler
> happy. A cast is fine in these cases because they are generic function
> pointer values that have been looked up in a DLL.
I have a more complete "fix" which I got stuck testing GGG[1]; you are likely
going to also hit -Wcast-function-type otherwise.
>
> Signed-off-by: Johannes Sixt <j6t@xxxxxxxx>
> ---
> How can this have worked ever without a warning?
POSIX have a specific exception that allows (void *) for this, it is incorrect
though in platforms where pointers to code and data might be different
(ex DOS with its segmented model)
Carlo
[1] https://github.com/git/git/pull/1094
