Hi! local_def in tail merging returned different results depending on if there are any debug uses in other bbs or not.
Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? 2012-01-30 Jakub Jelinek <ja...@redhat.com> PR debug/52048 * tree-ssa-tail-merge.c (local_def): Ignore debug uses. * g++.dg/other/pr52048.C: New test. --- gcc/tree-ssa-tail-merge.c.jj 2012-01-20 12:35:16.000000000 +0100 +++ gcc/tree-ssa-tail-merge.c 2012-01-30 09:23:05.392367800 +0100 @@ -371,6 +371,8 @@ local_def (tree val) res = true; FOR_EACH_IMM_USE_STMT (stmt, iter, val) { + if (is_gimple_debug (stmt)) + continue; bb = gimple_bb (stmt); if (bb == def_bb) continue; --- gcc/testsuite/g++.dg/other/pr52048.C.jj 2012-01-30 09:59:53.570759458 +0100 +++ gcc/testsuite/g++.dg/other/pr52048.C 2012-01-30 09:59:12.000000000 +0100 @@ -0,0 +1,79 @@ +// PR debug/52048 +// { dg-do compile } +// { dg-options "-fcompare-debug -fnon-call-exceptions -fno-tree-dominator-opts -O2" } + +template <typename T> struct A; +template <typename T> +struct A <T *> +{ + typedef T &a; +}; +template <typename T> +struct B +{ + typedef typename A <T>::a a; + a operator *() {} +}; +template <typename T, typename U> +bool operator != (B <T>, B <U>) +{ +} +template <typename T> +struct C +{ + typedef T *c; + template <typename> + struct D { typedef C d; }; +}; +template <typename T, typename U> struct E +{ + typedef typename U::template D <T>::d e; +}; +template <typename T, typename U = C <T> > +struct F +{ + typedef E <T, U> b; + typedef typename b::e e; + typedef typename e::c c; + typedef B <c> i; + i begin (); + i end (); +}; +class G; +class H; +struct I +{ + void *i; + template <typename T> T foo (); +}; +struct J : public I +{ + virtual bool bar (); +}; +class K {}; +struct L +{ + bool baz () {} +}; +struct M +{ + K m1 (K); + K m2 (H *) {} +}; +struct N : J +{ + bool bar (G &); +}; +bool +N::bar (G &) +{ + M m = foo <M> (); + F <H *> f; + for (F <H *>::i I = f.begin (), E = f.end (); I != E;) + { + H *h = *I; + L l; + if (l.baz ()) + m.m1 (m.m2 (h)); + } +} Jakub