On Wed, Jul 17, 2019 at 12:05:14AM +0200, Arnd Bergmann wrote: > On Tue, Jul 16, 2019 at 10:24 PM 'Nick Desaulniers' via Clang Built > Linux <[email protected]> wrote: > > > > On Fri, Jul 12, 2019 at 1:41 PM Arnd Bergmann <[email protected]> wrote: > > > > > > On Fri, Jul 12, 2019 at 6:59 PM 'Nick Desaulniers' via Clang Built > > > Linux <[email protected]> wrote: > > > > > The issue still needs to get fixed in clang regardless. There are > > > > > other > > > > > noreturn functions in the kernel and this problem could easily pop > > > > > back > > > > > up. > > > > > > > > Sure, thanks for the report. Arnd, can you help us get a more minimal > > > > test case to understand the issue better? > > > > > > I reduced it to this testcase: > > > > > > int a, b; > > > void __reiserfs_panic(int, ...) __attribute__((noreturn)); > > > void balance_internal() { > > > if (a) > > > __reiserfs_panic(0, "", __func__, "", 2, __func__, a); > > > if (b) > > > __reiserfs_panic(0, "", __func__, "", 5, __func__, a, 0); > > > } > > > > > > https://godbolt.org/z/Byfvmx > > > > Is this the same issue as Josh pointed out? IIUC, Josh pointed to a > > jump destination that was past a `push %rbp`, and I don't see it in > > your link. (Or, did I miss it?) > > I think it can be any push. The point is that the stack is different > between the two branches leading up to the noreturn call.
Right. -- Josh
