[PATCH] gimple: sccopy: Don't increment i after vec::unordered_remove()

[Filip Kastl]

Hi,

Ok to push if bootstrap and regtest (on x86_64 linux) succeeds?

Thanks,
Filip Kastl


-- 8< --


I increment the index variable in a loop even when I do
vec::unordered_remove() which causes the vector traversal to miss some
elements.  Mikael notified me of this mistake I made in my last patch.

gcc/ChangeLog:

        * gimple-ssa-sccopy.cc (scc_copy_prop::propagate): Don't
        increment after vec::unordered_remove().

Reported-by: Mikael Morin <mik...@gcc.gnu.org>
Signed-off-by: Filip Kastl <fka...@suse.cz>
---
 gcc/gimple-ssa-sccopy.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/gcc/gimple-ssa-sccopy.cc b/gcc/gimple-ssa-sccopy.cc
index 298feb05571..ee2a7fa8a72 100644
--- a/gcc/gimple-ssa-sccopy.cc
+++ b/gcc/gimple-ssa-sccopy.cc
@@ -582,9 +582,11 @@ scc_copy_prop::propagate ()
         get removed.  That means parts of CFG get removed.  Those may
         contain copy statements.  For that reason we prune SCCs here.  */
       unsigned i;
-      for (i = 0; i < scc.length (); i++)
+      for (i = 0; i < scc.length ();)
        if (gimple_bb (scc[i]) == NULL)
          scc.unordered_remove (i);
+       else
+         i++;
       if (scc.is_empty ())
        {
          scc.release ();
-- 
2.47.1