diff --git a/.circleci/config.yml b/.circleci/config.yml
index 2660506..6a68cfa 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -24,7 +24,7 @@ jobs:
           command: |
               g++ --version
               cd tests/
-              g++ -std=c++11 -O2 -Wall -Wextra -Wpedantic -Werror -I../ check_serialization.cpp -o check_serialization
+              g++ -std=c++11 -O2 -Wall -Wextra -Wpedantic -Werror -DTOML11_DISALLOW_HETEROGENEOUS_ARRAYS -I../ check_serialization.cpp -o check_serialization
               git clone https://github.com/BurntSushi/toml-test.git
               cp check_serialization toml-test/tests/valid
               cd toml-test/tests/valid
@@ -47,7 +47,7 @@ jobs:
           command: |
               g++ --version
               cd tests/
-              g++ -std=c++11 -O2 -Wall -Wextra -Wpedantic -Werror -I../ check.cpp -o check
+              g++ -std=c++11 -O2 -Wall -Wextra -Wpedantic -Werror -DTOML11_DISALLOW_HETEROGENEOUS_ARRAYS -I../ check.cpp -o check
               git clone https://github.com/BurntSushi/toml-test.git
               cp check toml-test/tests/invalid
               cp check toml-test/tests/valid