Hi Yuri,
On Mar 30 23:00, Yuyi Wang wrote:
> dlclose tries to decrease the ref count of the dll* entry, but a new dll
> opened by dlopen doesn't create a new dll* entry.
> ---
> winsup/cygwin/dlfcn.cc | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/winsup/cygwin/dlfcn.cc b/winsup/cygwin/dlfcn.cc
> index fb7052473..3093ec1be 100644
> --- a/winsup/cygwin/dlfcn.cc
> +++ b/winsup/cygwin/dlfcn.cc
> @@ -350,14 +350,15 @@ dlclose (void *handle)
> {
> /* reference counting */
> dll *d = dlls.find (handle);
> - if (!d || d->count <= 0)
> + if (d && d->count <= 0)
> {
> errno = ENOENT;
> ret = -1;
> }
> else
> {
> - --d->count;
> + if (d)
> + --d->count;
> if (!FreeLibrary ((HMODULE) handle))
> {
> __seterrno ();
> --
> 2.48.1.windows.1-2
Thanks for the patch, but that's not the right way to fix this issue,
afaics. I tested this scenario, and this problem only occurs with
dlopening cygwin1.dll.
The reason is that the dll_list::find method returns NULL if the found
DLL is cygwin1.dll. This makes sense for other places where the method
is used, but it doesn't make sense for dlopen/dlclose.
So dll_list::find needs a way to return the dll pointer so we can
refcount cygwin1.dll like any other DLL so dlclose succeeds.
While looking into it, I found another refcount problem in terms of
RTLD_NODELETE. I fixed that too.
Please give the next test release cygwin-3.7.0-0.24.g98112b9f6f90
a try.
Thanks,
Corinna
