diff --git a/scripts/compiler_tests/build_all.sh b/scripts/compiler_tests/build_all.sh
index 1f1ffc6..aeec792 100755
--- a/scripts/compiler_tests/build_all.sh
+++ b/scripts/compiler_tests/build_all.sh
@@ -11,12 +11,12 @@ if [ $? -ne 0 ]; then
 	images/ubuntu/build.sh
 fi
 
-for i in 8 9 10 11 12 13 14 15;
+for i in 8 15;
 do
 	gcc/build.sh $1 $i
 done
 
-for i in 17 18 19 20;
+for i in 17 21;
 do
 	clang/build.sh $1 $i
 done
diff --git a/scripts/compiler_tests/clang/Dockerfile b/scripts/compiler_tests/clang/Dockerfile
index 97e87aa..3acbc90 100644
--- a/scripts/compiler_tests/clang/Dockerfile
+++ b/scripts/compiler_tests/clang/Dockerfile
@@ -1,4 +1,4 @@
 FROM p2pool_compiler_tests_ubuntu
-ARG P2POOL_VERSION GCC_VERSION
+ARG P2POOL_VERSION CLANG_VERSION
 ADD test.sh test2.sh /p2pool/
-RUN /p2pool/test.sh ${P2POOL_VERSION} ${GCC_VERSION}
+RUN /p2pool/test.sh ${P2POOL_VERSION} ${CLANG_VERSION}
diff --git a/scripts/compiler_tests/clang/build.sh b/scripts/compiler_tests/clang/build.sh
index cdf93da..8a23227 100755
--- a/scripts/compiler_tests/clang/build.sh
+++ b/scripts/compiler_tests/clang/build.sh
@@ -4,7 +4,7 @@
 
 cd "$(dirname "$0")"
 
-docker build --build-arg P2POOL_VERSION=$1 --build-arg GCC_VERSION=$2 -t p2pool_compiler_test_clang_$1_$2 .
+docker build --build-arg P2POOL_VERSION=$1 --build-arg CLANG_VERSION=$2 -t p2pool_compiler_test_clang_$1_$2 .
 
 docker create --name p2pool_compiler_test_clang_$1_$2_container p2pool_compiler_test_clang_$1_$2:latest
 docker cp p2pool_compiler_test_clang_$1_$2_container:/p2pool/logs.tar.gz clang_$2_logs.tar.gz
diff --git a/scripts/compiler_tests/images/ubuntu/prepare.sh b/scripts/compiler_tests/images/ubuntu/prepare.sh
index a1192fc..56f0ea2 100755
--- a/scripts/compiler_tests/images/ubuntu/prepare.sh
+++ b/scripts/compiler_tests/images/ubuntu/prepare.sh
@@ -127,7 +127,7 @@ cd /root
 curl -L -O https://apt.llvm.org/llvm.sh
 chmod +x llvm.sh
 
-for i in 17 18 19 20;
+for i in 17 18 19 20 21;
 do
 	./llvm.sh $i
 done