Give a constant a name
diff --git a/library/ecp.c b/library/ecp.c
index 47c7da2..7bcf256 100644
--- a/library/ecp.c
+++ b/library/ecp.c
@@ -1334,6 +1334,7 @@
     int ret;
     unsigned char i;
     size_t j;
+    const unsigned char T_len = 1U << ( w - 1 );
     mbedtls_ecp_point *cur, *TT[COMB_MAX_PRE - 1];
 
 #if defined(MBEDTLS_ECP_EARLY_RETURN)
@@ -1351,7 +1352,7 @@
      */
     MBEDTLS_MPI_CHK( mbedtls_ecp_copy( &T[0], P ) );
 
-    for( i = 1; i < ( 1U << ( w - 1 ) ); i <<= 1 )
+    for( i = 1; i < T_len; i <<= 1 )
     {
         cur = T + i;
         MBEDTLS_MPI_CHK( mbedtls_ecp_copy( cur, T + ( i >> 1 ) ) );
@@ -1364,7 +1365,7 @@
      * use an auxiliary array of pointers to elements in T.
      */
     j = 0;
-    for( i = 1; i < ( 1U << ( w - 1 ) ); i <<= 1 )
+    for( i = 1; i < T_len; i <<= 1 )
         TT[j++] = T + i;
 
     MBEDTLS_MPI_CHK( ecp_normalize_jac_many( grp, TT, j ) );
@@ -1373,7 +1374,7 @@
      * Compute the remaining ones using the minimal number of additions
      * Be careful to update T[2^l] only after using it!
      */
-    for( i = 1; i < ( 1U << ( w - 1 ) ); i <<= 1 )
+    for( i = 1; i < T_len; i <<= 1 )
     {
         j = i;
         while( j-- )
@@ -1383,9 +1384,9 @@
     /*
      * Normalize final elements in T. Even though there are no holes now,
      * we still need the auxiliary array for homogeneity with last time.
-     * Also skip T[0] which is already normalised, being a copy of P.
+     * Also, skip T[0] which is already normalised, being a copy of P.
      */
-    for( j = 0; j + 1 < ( 1U << ( w - 1 ) ); j++ )
+    for( j = 0; j + 1 < T_len; j++ )
         TT[j] = T + j + 1;
 
     MBEDTLS_MPI_CHK( ecp_normalize_jac_many( grp, TT, j ) );