re PR middle-end/84233 (ICE (segfault) in gimple_assign_rhs_code)

2018-02-08  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/84233
	* tree-ssa-phiprop.c (propagate_with_phi): Use separate
	changed flag instead of boguously re-using phi_inserted.

	* g++.dg/torture/pr84233.C: New testcase.

From-SVN: r257486

gcc/ChangeLog

+2018-02-08  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/84233
+	* tree-ssa-phiprop.c (propagate_with_phi): Use separate
+	changed flag instead of boguously re-using phi_inserted.
+
 2018-02-08  Martin Jambor  <mjambor@suse.cz>
 
 	* hsa-gen.c (get_symbol_for_decl): Set program allocation for

gcc/testsuite/ChangeLog

 2018-02-08  Richard Biener  <rguenther@suse.de>
 
+	PR tree-optimization/84233
+	* g++.dg/torture/pr84233.C: New testcase.
+
+2018-02-08  Richard Biener  <rguenther@suse.de>
+
 	PR tree-optimization/84278
 	* gcc.target/i386/pr84278.c: New testcase.
 

gcc/testsuite/g++.dg/torture/pr84233.C

+// { dg-do compile }
+// { dg-additional-options "-w" }
+
+void a(const char *, int, const char *, const char *);
+template <typename b> void c(b);
+struct d {
+    long e;
+    template <typename> union f;
+    template <typename h> union f<h *> {
+	f(h *i) : j(i) {}
+	h *j;
+	long bits;
+    };
+    static int k(volatile long &i) { return *(int *)f<volatile long *>(&i).bits; }
+    typedef long g;
+    operator g() volatile {
+	int l = k(e);
+	c(l);
+    }
+};
+struct : d {
+	 } m, n;
+bool o;
+void p() { (o ? m : n) ? (void)0 : a("", 5, "", ""); }
+

gcc/tree-ssa-phiprop.c

@@ -270,6 +270,7 @@ propagate_with_phi (basic_block bb, gphi *phi, struct phiprop_d *phivn,
   use_operand_p arg_p, use;
   ssa_op_iter i;
   bool phi_inserted;
+  bool changed;
   tree type = NULL_TREE;
 
   if (!POINTER_TYPE_P (TREE_TYPE (ptr))
@@ -317,6 +318,7 @@ propagate_with_phi (basic_block bb, gphi *phi, struct phiprop_d *phivn,
   /* Replace the first dereference of *ptr if there is one and if we
      can move the loads to the place of the ptr phi node.  */
   phi_inserted = false;
+  changed = false;
   FOR_EACH_IMM_USE_STMT (use_stmt, ui, ptr)
     {
       gimple *def_stmt;
@@ -403,7 +405,7 @@ propagate_with_phi (basic_block bb, gphi *phi, struct phiprop_d *phivn,
 	  unlink_stmt_vdef (use_stmt);
 	  gsi_remove (&gsi, true);
 
-	  phi_inserted = true;
+	  changed = true;
 	}
 
       /* Found a proper dereference.  Insert a phi node if this
@@ -424,6 +426,7 @@ propagate_with_phi (basic_block bb, gphi *phi, struct phiprop_d *phivn,
 	  gsi_remove (&gsi, true);
 
 	  phi_inserted = true;
+	  changed = true;
 	}
       else
 	{
@@ -431,13 +434,14 @@ propagate_with_phi (basic_block bb, gphi *phi, struct phiprop_d *phivn,
 	     load.  */
 	  gimple_assign_set_rhs1 (use_stmt, res);
 	  update_stmt (use_stmt);
+	  changed = true;
 	}
 
 next:;
       /* Continue searching for a proper dereference.  */
     }
 
-  return phi_inserted;
+  return changed;
 }
 
 /* Main entry for phiprop pass.  */