crypto/gc-md2: optimize and clarify code

[Bruno Haible]

Make lib/gc-gnulib.c and lib/gc-libgcrypt.c more consistent with each other.


2019-08-24  Bruno Haible  <address@hidden>

        crypto/gc-md2: Optimize and clarify code.
        * lib/gc-gnulib.c (gc_hash_open): Comment out md2_init_ctx invocation.
        * lib/gc-libgcrypt.c (gc_hash_open): Clarify why md2_init_ctx invocation
        is not needed.

diff --git a/lib/gc-gnulib.c b/lib/gc-gnulib.c
index 62aa50a..6fcb4a1 100644
--- a/lib/gc-gnulib.c
+++ b/lib/gc-gnulib.c
@@ -646,7 +646,8 @@ gc_hash_open (Gc_hash hash, Gc_hash_mode mode, 
gc_hash_handle * outhandle)
     {
 #if GNULIB_GC_MD2
     case GC_MD2:
-      md2_init_ctx (&ctx->md2Context);
+      /* Not needed, because ctx is already zero-initialized.  */
+      /*md2_init_ctx (&ctx->md2Context);*/
       break;
 #endif
 
diff --git a/lib/gc-libgcrypt.c b/lib/gc-libgcrypt.c
index 6c95712..fbfd0a1 100644
--- a/lib/gc-libgcrypt.c
+++ b/lib/gc-libgcrypt.c
@@ -270,9 +270,13 @@ gc_hash_open (Gc_hash hash, Gc_hash_mode mode, 
gc_hash_handle * outhandle)
 
   switch (hash)
     {
+#if GNULIB_GC_MD2
     case GC_MD2:
+      /* Not needed, because ctx is already zero-initialized.  */
+      /*md2_init_ctx (&ctx->md2Context);*/
       gcryalg = GCRY_MD_NONE;
       break;
+#endif
 
     case GC_MD4:
       gcryalg = GCRY_MD_MD4;