diff --git a/trezor-crypto/CMakeLists.txt b/trezor-crypto/CMakeLists.txt
index 238dbc31217..a3ef46a38f2 100644
--- a/trezor-crypto/CMakeLists.txt
+++ b/trezor-crypto/CMakeLists.txt
@@ -23,6 +23,8 @@ set(TW_WARNING_FLAGS
     -Wno-missing-braces
 )
 
+set(CMAKE_C_STANDARD 11)
+
 add_library(TrezorCrypto
     crypto/bignum.c crypto/ecdsa.c crypto/curves.c crypto/secp256k1.c crypto/rand.c crypto/hmac.c crypto/bip32.c crypto/bip39.c crypto/slip39.c crypto/pbkdf2.c crypto/base58.c crypto/base32.c
     crypto/address.c