Thank you.
I don't know what's so special about my setup - I am getting the same error
with GCC 12 & 13 - compiling for both x86_64 & aarch64.
Compiler flags - nothing unusual - -O3 -flto - but maybe warnings are a
bit overzealous (-Wuninitialized -Wstack-protector).
I'll try producing a sample that reproduces this - and will use suggested
workaround in the meantime.
On Tue, 26 Dec 2023 at 17:21, Evgeny Grin <k...@yandex.ru> wrote:
> Hi Sergey,
>
> Are you using some special compiler or linker parameters? Some special
> compiler or linker versions?
>
> I regularly test MHD with LTO. I've retested the current git master with
> LTO and cannot reproduce.
> No errors, nor even warnings.
>
> If you check the code you will find that both mentioned variables are
> not used before initialisation. (Please provide the code path if I'm
> wrong).
>
> Unless variables are really used as uninitialised (which should be a bug
> and needs to be fixed), I'd avoid unneeded initialisation to save the
> code size (and negligible performance).
>
> If your compiler/linker complaint is false positive, you probably may
> workaround it with '-ftrivial-auto-var-init' parameter.
>
> Let me know the details, please.
>
> --
> Evgeny
>
> On 26/12/2023 16:14, Sergey Sudnitsyn wrote:
> > When LTO is enabled, linking fails complaining about potentially
> > uninitialized variables;
> > It's hard to provide a small sample reproducing this, but I hope the
> > patch can be applied even without it since it's innocent enough (diff
> > against commit 8bb481f ):
> >
> > diff --git a/src/microhttpd/connection.c b/src/microhttpd/connection.c
> > index f9892a55..e5dd1a45 100644
> > --- a/src/microhttpd/connection.c
> > +++ b/src/microhttpd/connection.c
> > @@ -653,7 +653,7 @@ MHD_connection_alloc_memory_ (struct MHD_Connection
> > *connection,
> > {
> > struct MHD_Connection *const c = connection; /* a short alias */
> > struct MemoryPool *const pool = c->pool; /* a short alias */
> > - size_t need_to_be_freed; /**< The required amount of additional free
> > memory */
> > + size_t need_to_be_freed = 0; /**< The required amount of additional
> > free memory */
> > void *res;
> >
> > res = MHD_pool_try_alloc (pool, size, &need_to_be_freed);
> > @@ -4468,7 +4468,7 @@ process_request_body (struct MHD_Connection
> > *connection)
> > { /* Need the parse the chunk size line */
> > /** The number of found digits in the chunk size number */
> > size_t num_dig;
> > - uint64_t chunk_size;
> > + uint64_t chunk_size = 0;
> > bool broken;
> > bool overflow;
> >
>
