[PATCH] Fix PR82902

[Richard Biener]

The following fixes PR82902.

Bootstrapped and tested on x86_64-unknown-linux-gnu, applied.

Richard.

2017-11-09  Richard Biener  <rguent...@suse.de>

        PR tree-optimization/82902
        * tree-ssa-phiprop.c (propagate_with_phi): Test proper type.

        * g++.dg/torture/pr82902.C: New testcase.

Index: gcc/tree-ssa-phiprop.c
===================================================================
--- gcc/tree-ssa-phiprop.c      (revision 254560)
+++ gcc/tree-ssa-phiprop.c      (working copy)
@@ -354,7 +354,7 @@ propagate_with_phi (basic_block bb, gphi
 
       /* Found a proper dereference with an aggregate copy.  Just
          insert aggregate copies on the edges instead.  */
-      if (!is_gimple_reg_type (TREE_TYPE (TREE_TYPE (ptr))))
+      if (!is_gimple_reg_type (TREE_TYPE (gimple_assign_lhs (use_stmt))))
        {
          if (!gimple_vdef (use_stmt))
            goto next;
Index: gcc/testsuite/g++.dg/torture/pr82902.C
===================================================================
--- gcc/testsuite/g++.dg/torture/pr82902.C      (nonexistent)
+++ gcc/testsuite/g++.dg/torture/pr82902.C      (working copy)
@@ -0,0 +1,21 @@
+// { dg-do compile }
+
+typedef struct el_t {
+    el_t *next;
+    int elem[];
+} EL;
+el_t a, c;
+void *b;
+void *fn1() {
+    if (b)
+      return a.elem;
+    return c.elem;
+}
+typedef struct {
+    int x;
+} EV_T;
+EV_T *d;
+void fn2() {
+    EV_T *e = (EV_T *)fn1();
+    d[0] = *e;
+}