diff --git a/contrib/devtools/git-subtree-check.sh b/contrib/devtools/git-subtree-check.sh
index 2384d66cad2aa..446db59167d71 100755
--- a/contrib/devtools/git-subtree-check.sh
+++ b/contrib/devtools/git-subtree-check.sh
@@ -18,7 +18,7 @@ find_latest_squash()
 	sub=
 	git log --grep="^git-subtree-dir: $dir/*\$" \
 		--pretty=format:'START %H%n%s%n%n%b%nEND%n' "$COMMIT" |
-	while read a b junk; do
+	while read a b _; do
 		case "$a" in
 			START) sq="$b" ;;
 			git-subtree-mainline:) main="$b" ;;
@@ -48,7 +48,6 @@ if [ -z "$latest_squash" ]; then
 fi
 
 set $latest_squash
-old=$1
 rev=$2
 if [ "d$(git cat-file -t $rev 2>/dev/null)" != dcommit ]; then
     echo "ERROR: subtree commit $rev unavailable. Fetch/update the subtree repository" >&2
diff --git a/contrib/gitian-build.sh b/contrib/gitian-build.sh
index 8fdec21b0e88f..511c1a4c481db 100755
--- a/contrib/gitian-build.sh
+++ b/contrib/gitian-build.sh
@@ -6,7 +6,6 @@
 sign=false
 verify=false
 build=false
-setupenv=false
 
 # Systems to build
 linux=true
diff --git a/contrib/verify-commits/verify-commits.sh b/contrib/verify-commits/verify-commits.sh
index 7194b040eb610..a1ef715fb3f7f 100755
--- a/contrib/verify-commits/verify-commits.sh
+++ b/contrib/verify-commits/verify-commits.sh
@@ -12,8 +12,6 @@ VERIFIED_ROOT=$(cat "${DIR}/trusted-git-root")
 VERIFIED_SHA512_ROOT=$(cat "${DIR}/trusted-sha512-root-commit")
 REVSIG_ALLOWED=$(cat "${DIR}/allow-revsig-commits")
 
-HAVE_FAILED=false
-
 HAVE_GNU_SHA512=1
 [ ! -x "$(which sha512sum)" ] && HAVE_GNU_SHA512=0
 
@@ -95,9 +93,9 @@ while true; do
 		FILE_HASHES=""
 		for FILE in $(git ls-tree --full-tree -r --name-only "$CURRENT_COMMIT" | LC_ALL=C sort); do
 			if [ "$HAVE_GNU_SHA512" = 1 ]; then
-				HASH=$(git cat-file blob "$CURRENT_COMMIT":"$FILE" | sha512sum | { read FIRST OTHER; echo $FIRST; } )
+				HASH=$(git cat-file blob "$CURRENT_COMMIT":"$FILE" | sha512sum | { read FIRST _; echo $FIRST; } )
 			else
-				HASH=$(git cat-file blob "$CURRENT_COMMIT":"$FILE" | shasum -a 512 | { read FIRST OTHER; echo $FIRST; } )
+				HASH=$(git cat-file blob "$CURRENT_COMMIT":"$FILE" | shasum -a 512 | { read FIRST _; echo $FIRST; } )
 			fi
 			[ "$FILE_HASHES" != "" ] && FILE_HASHES="$FILE_HASHES"'
 '
diff --git a/contrib/verifybinaries/verify.sh b/contrib/verifybinaries/verify.sh
index 409f517c9fb26..320add64d0beb 100755
--- a/contrib/verifybinaries/verify.sh
+++ b/contrib/verifybinaries/verify.sh
@@ -76,8 +76,6 @@ if [ -n "$1" ]; then
          BASEDIR="$BASEDIR$RCSUBDIR.$RCVERSION/"
       fi
    fi
-
-   SIGNATUREFILE="$BASEDIR$SIGNATUREFILENAME"
 else
    echo "Error: need to specify a version on the command line"
    exit 2