Messages in this thread | | | From | Arnd Bergmann <> | Date | Fri, 3 Mar 2017 09:58:54 +0100 | Subject | Re: [PATCH] [RFC] x86: avoid -mtune=atom for objtool warnings |
| |
On Fri, Mar 3, 2017 at 12:05 AM, Josh Poimboeuf <jpoimboe@redhat.com> wrote:
> I assume '-Wdiv-by-zero' is enabled and gcc isn't showing the "division > by zero" warning for either of these? The 'ud2' is guaranteed to > trigger since the function has no branches. Surely at least the missing > warning is a gcc bug. > > The good news is objtool is flushing these out, albeit with a confusing > message.
I'm still not sure if it's intentional or not. I've reduced the test case to the simple
static inline int return0(void) { return 0; } int provoke_div0_warning(void) { return 1 / return0(); }
which does not generate a compile-time warning, but will generate an unconditional runtime warning if built with -fsanitze=integer-divide-by-zero.
Arnd
| |