diff --git a/library/bignum.c b/library/bignum.c
index eb7a82257..680c25a93 100644
--- a/library/bignum.c
+++ b/library/bignum.c
@@ -1527,6 +1527,7 @@ int mpi_exp_mod( mpi *X, const mpi *A, const mpi *E, const mpi *N, mpi *_RR )
      */
     mpi_montg_init( &mm, N );
     mpi_init( &RR ); mpi_init( &T );
+    mpi_init( &Apos );
     memset( W, 0, sizeof( W ) );
 
     i = mpi_msb( E );
@@ -1546,8 +1547,6 @@ int mpi_exp_mod( mpi *X, const mpi *A, const mpi *E, const mpi *N, mpi *_RR )
      * Compensate for negative A (and correct at the end)
      */
     neg = ( A->s == -1 );
-
-    mpi_init( &Apos );
     if( neg )
     {
         MPI_CHK( mpi_copy( &Apos, A ) );