| Message ID | e4f2bf68-39db-3321-a4c6-8c1bebb30f76@suse.cz |
|---|---|
| State | New |
| Headers | show |
| Series | Do not use tree_to_wide_ref that point to a temporary (PR c++/90587). | expand |
On Thu, May 23, 2019 at 12:51 PM Martin Liška <mliska@suse.cz> wrote: > > Hi. > > The PR is about use-after-scope issue where: > wi::tree_to_wide_ref andw = wi::to_wide (val) & wi::to_wide (boundary); > > The RHS1 and RHS2 will become out-of-scope after operator& returns a reference. > andw.val then points to one of RHS1 or RHS2. So that we end up with an use-after-scope. > > Patch can bootstrap on x86_64-linux-gnu and survives regression tests. > > Ready to be installed? OK. Richard. > Thanks, > Martin > > gcc/ChangeLog: > > 2019-05-23 Martin Liska <mliska@suse.cz> > > PR c++/90587. > * tree-ssa-uninit.c (value_sat_pred_p): The result of & > operation points to a temporary (pointed via tree_to_wide_ref) > that is out of scope after the &. > --- > gcc/tree-ssa-uninit.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > >
diff --git a/gcc/tree-ssa-uninit.c b/gcc/tree-ssa-uninit.c index bc07afe32c8..fe8f8f0bc28 100644 --- a/gcc/tree-ssa-uninit.c +++ b/gcc/tree-ssa-uninit.c @@ -1058,7 +1058,7 @@ value_sat_pred_p (tree val, tree boundary, enum tree_code cmpc, if (cmpc != BIT_AND_EXPR) return is_value_included_in (val, boundary, cmpc); - wi::tree_to_wide_ref andw = wi::to_wide (val) & wi::to_wide (boundary); + wide_int andw = wi::to_wide (val) & wi::to_wide (boundary); if (exact_p) return andw == wi::to_wide (val); else