[tor-commits] [tor/master] Add -Wunused-const-variable=2 on GCC >=6.1

[nickm at torproject.org]

commit 2ff20c93a5ec753a0c46ca5ecd991b8e2020f7d0
Author: Nick Mathewson <nickm at torproject.org>
Date:   Mon May 30 12:28:55 2016 -0400

    Add -Wunused-const-variable=2 on GCC >=6.1
    
    This caused a trivial warning in curve25519-donna-64bit.h, which
    had two unused constants.  I commented them out.
---
 configure.ac                                   | 1 +
 src/ext/ed25519/donna/curve25519-donna-64bit.h | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index d9149e2..f66d798 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1778,6 +1778,7 @@ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [
      CFLAGS="$CFLAGS -Wignored-attributes -Wshift-negative-value -Wshift-overflow=2"
      CFLAGS="$CFLAGS -Wnull-dereference"
      CFLAGS="$CFLAGS -Wduplicated-cond"
+     CFLAGS="$CFLAGS -Wunused-const-variable=2"
   fi
 
   if test "x$have_shorten64_flag" = "xyes"; then
diff --git a/src/ext/ed25519/donna/curve25519-donna-64bit.h b/src/ext/ed25519/donna/curve25519-donna-64bit.h
index 2941d1b..50c9916 100644
--- a/src/ext/ed25519/donna/curve25519-donna-64bit.h
+++ b/src/ext/ed25519/donna/curve25519-donna-64bit.h
@@ -8,9 +8,9 @@
 
 typedef uint64_t bignum25519[5];
 
-static const uint64_t reduce_mask_40 = ((uint64_t)1 << 40) - 1;
+//static const uint64_t reduce_mask_40 = ((uint64_t)1 << 40) - 1;
 static const uint64_t reduce_mask_51 = ((uint64_t)1 << 51) - 1;
-static const uint64_t reduce_mask_56 = ((uint64_t)1 << 56) - 1;
+//static const uint64_t reduce_mask_56 = ((uint64_t)1 << 56) - 1;
 
 /* out = in */
 DONNA_INLINE static void