gdb:

	* value.h (value_non_lval): Declare.
	* value.c (value_non_lval): New function.
	* eval.c (evaluate_subexp_standard) <UNOP_POSTINCREMENT,
	UNOP_POSTDECREMENT>: Call value_non_lval to ensure to return a
	non-lvalue.

gdb/testsuite:
	* gdb.base/exprs.exp: Add tests for pre-/post- in-/decrement operators.

1 files changed, 6 insertions, 2 deletions

diff --git a/gdb/eval.c b/gdb/eval.c
index 471dcd7..71c3ff8 100644
--- a/gdb/eval.c
+++ b/gdb/eval.c
@@ -2782,6 +2782,8 @@ evaluate_subexp_standard (struct type *expect_type,
 	}
       else
 	{
+	  arg3 = value_non_lval (arg1);
+
 	  if (ptrmath_type_p (exp->language_defn, value_type (arg1)))
 	    arg2 = value_ptradd (arg1, 1);
 	  else
@@ -2794,7 +2796,7 @@ evaluate_subexp_standard (struct type *expect_type,
 	    }
 
 	  value_assign (arg1, arg2);
-	  return arg1;
+	  return arg3;
 	}
 
     case UNOP_POSTDECREMENT:
@@ -2807,6 +2809,8 @@ evaluate_subexp_standard (struct type *expect_type,
 	}
       else
 	{
+	  arg3 = value_non_lval (arg1);
+
 	  if (ptrmath_type_p (exp->language_defn, value_type (arg1)))
 	    arg2 = value_ptradd (arg1, -1);
 	  else
@@ -2819,7 +2823,7 @@ evaluate_subexp_standard (struct type *expect_type,
 	    }
 
 	  value_assign (arg1, arg2);
-	  return arg1;
+	  return arg3;
 	}
 
     case OP_THIS: