diff --git a/src/mod.c b/src/mod.c
index 9801599..2cbe8e4 100644
--- a/src/mod.c
+++ b/src/mod.c
@@ -131,6 +131,7 @@ mod_reduce (bn256 *X, const bn512 *A, const bn256 *B, const bn256 *MU_lower)
     memcpy (q, X, sizeof (bn256));
   else
     memcpy (X, q, sizeof (bn256));
+#undef borrow
 }
 
 /**
@@ -339,4 +340,5 @@ mod_inv (bn256 *C, const bn256 *X, const bn256 *N)
 	  break;
 	}
     }
+#undef borrow
 }
diff --git a/src/modp256.c b/src/modp256.c
index eb763c6..bf2cbde 100644
--- a/src/modp256.c
+++ b/src/modp256.c
@@ -432,4 +432,5 @@ modp256_shift (bn256 *X, const bn256 *A, int shift)
     memcpy (tmp, X, sizeof (bn256));
   else
     memcpy (X, tmp, sizeof (bn256));
+#undef borrow
 }