On 2/20/20 1:37 AM, Jürgen Groß wrote: > On 20.02.20 07:23, Kees Cook wrote: >> Variables declared in a switch statement before any case statements >> cannot be automatically initialized with compiler instrumentation (as >> they are not part of any execution flow). With GCC's proposed automatic >> stack variable initialization feature, this triggers a warning (and they >> don't get initialized). Clang's automatic stack variable initialization >> (via CONFIG_INIT_STACK_ALL=y) doesn't throw a warning, but it also >> doesn't initialize such variables[1]. Note that these warnings (or >> silent >> skipping) happen before the dead-store elimination optimization phase, >> so even when the automatic initializations are later elided in favor of >> direct initializations, the warnings remain. >> >> To avoid these problems, move such variables into the "case" where >> they're used or lift them up into the main function body. >> >> arch/x86/xen/enlighten_pv.c: In function ‘xen_write_msr_safe’: >> arch/x86/xen/enlighten_pv.c:904:12: warning: statement will never be >> executed [-Wswitch-unreachable] >> 904 | unsigned which; >> | ^~~~~ >> >> [1] https://bugs.llvm.org/show_bug.cgi?id=44916 >> >> Signed-off-by: Kees Cook <keesc...@chromium.org> > > Reviewed-by: Juergen Gross <jgr...@suse.com> >
Applied to for-linus-5.6. (I replaced 'unsigned' with 'unsigned int' to quiet down checkpatch ) -boris _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
