diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index fdb84d1d423..cd64b59bf08 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2013-12-14  Marek Polacek  <polacek@redhat.com>
+
+	PR sanitizer/59503
+	* internal-fn.c (ubsan_expand_si_overflow_addsub_check): Call
+	expand_binop with correct optab depending on code.
+
 2013-12-14  Tom de Vries  <tom@codesourcery.com>
 
 	* calls.c (expand_call): Fix REG_PARM_STACK_SPACE comparison.
diff --git a/gcc/internal-fn.c b/gcc/internal-fn.c
index ad9c9475265..a0874d467b4 100644
--- a/gcc/internal-fn.c
+++ b/gcc/internal-fn.c
@@ -214,14 +214,14 @@ ubsan_expand_si_overflow_addsub_check (tree_code code, gimple stmt)
 
       /* Compute the operation.  On RTL level, the addition is always
 	 unsigned.  */
-      res = expand_binop (mode, add_optab, op0, op1,
-			  NULL_RTX, false, OPTAB_LIB_WIDEN);
+      res = expand_binop (mode, code == PLUS_EXPR ? add_optab : sub_optab,
+			  op0, op1, NULL_RTX, false, OPTAB_LIB_WIDEN);
 
       /* If the op1 is negative, we have to use a different check.  */
       emit_cmp_and_jump_insns (op1, const0_rtx, LT, NULL_RTX, mode,
 			       false, sub_check, PROB_EVEN);
 
-      /* Compare the result of the addition with one of the operands.  */
+      /* Compare the result of the operation with one of the operands.  */
       emit_cmp_and_jump_insns (res, op0, code == PLUS_EXPR ? GE : LE,
 			       NULL_RTX, mode, false, done_label,
 			       PROB_VERY_LIKELY);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 91dcb335bb1..b5fabb2baf1 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2013-12-14  Marek Polacek  <polacek@redhat.com>
+
+	PR sanitizer/59503
+	* c-c++-common/ubsan/pr59503.c: New test.
+
 2013-12-14  Janus Weil  <janus@gcc.gnu.org>
 
 	PR fortran/59450
diff --git a/gcc/testsuite/c-c++-common/ubsan/pr59503.c b/gcc/testsuite/c-c++-common/ubsan/pr59503.c
new file mode 100644
index 00000000000..eb921c4ff18
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/ubsan/pr59503.c
@@ -0,0 +1,14 @@
+/* { dg-do run } */
+/* { dg-options "-fsanitize=signed-integer-overflow" } */
+/* { dg-skip-if "" { *-*-* } { "-flto" } { "" } } */
+
+int
+main (void)
+{
+  long long int a = 14;
+  long int b = 9;
+  asm volatile ("" : "+r" (a), "+r" (b));
+  if ((a - b) != 5)
+    __builtin_abort ();
+  return 0;
+}