diff --git a/gcc/testsuite/gcc.c-torture/compile/pr108783.c b/gcc/testsuite/gcc.c-torture/compile/pr108783.c
new file mode 100644
index 00000000000..eae87db36d7
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr108783.c
@@ -0,0 +1,42 @@
+/* PR tree-optimization/108783 */
+
+__attribute__((returns_twice)) int baz (int, int);
+
+int
+bar (int x)
+{
+  return x;
+}
+
+int
+foo (int x, int y)
+{
+  int a;
+
+  a = bar (x);
+  baz (x, y);
+
+  return y && a && a;
+}
+
+int
+qux (int x, int y)
+{
+  int a;
+
+  a = bar (x);
+  baz (x, y);
+
+  return y && a != 42 && a >= 42;
+}
+
+int
+corge (int x, int y)
+{
+  int a;
+
+  a = bar (x);
+  baz (x, y);
+
+  return y || a == 42 || a > 42;
+}
diff --git a/gcc/tree-ssa-reassoc.cc b/gcc/tree-ssa-reassoc.cc
index 5522a3ada8e..f163612f140 100644
--- a/gcc/tree-ssa-reassoc.cc
+++ b/gcc/tree-ssa-reassoc.cc
@@ -2272,6 +2272,15 @@ eliminate_redundant_comparison (enum tree_code opcode,
 	  STRIP_USELESS_TYPE_CONVERSION (newop2);
 	  if (!is_gimple_val (newop1) || !is_gimple_val (newop2))
 	    continue;
+	  if (lcode == TREE_CODE (t)
+	      && operand_equal_p (op1, newop1, 0)
+	      && operand_equal_p (op2, newop2, 0))
+	    t = curr->op;
+	  else if ((TREE_CODE (newop1) == SSA_NAME
+		    && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (newop1))
+		   || (TREE_CODE (newop2) == SSA_NAME
+		       && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (newop2)))
+	    continue;
 	}
 
       if (dump_file && (dump_flags & TDF_DETAILS))