Merge remote-tracking branch 'origin/pr/2578' into mbedtls-2.16

* origin/pr/2578:
  Remove a redundant function call
diff --git a/ChangeLog b/ChangeLog
index de64acf..59797bd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,6 +2,11 @@
 
 = mbed TLS 2.16.x branch released xxxx-xx-xx
 
+Bugfix
+   * Remove redundant line for getting the bitlen of a bignum, since the variable
+     holding the returned value is overwritten a line after.
+     Found by irwir in #2377.
+
 Changes
    * Add unit tests for AES-GCM when called through mbedtls_cipher_auth_xxx()
      from the cipher abstraction layer. Fixes #2198.
diff --git a/library/bignum.c b/library/bignum.c
index d1717e9..7a700bc 100644
--- a/library/bignum.c
+++ b/library/bignum.c
@@ -2338,8 +2338,6 @@
     MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &R, &W ) );
     MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &R, s ) );
 
-    i = mbedtls_mpi_bitlen( X );
-
     for( i = 0; i < rounds; i++ )
     {
         /*