diff --git a/configs/olimex_a20_olinuxino_lime_legacy_defconfig b/configs/olimex_a20_olinuxino_lime_legacy_defconfig
index c14c2ca995..2c33f05e56 100644
--- a/configs/olimex_a20_olinuxino_lime_legacy_defconfig
+++ b/configs/olimex_a20_olinuxino_lime_legacy_defconfig
@@ -3,6 +3,9 @@ BR2_arm=y
 BR2_cortex_a7=y
 BR2_ARM_EABIHF=y
 
+# The old 3.4 kernel doesn't build with gcc >= 7.x
+BR2_GCC_VERSION_6_X=y
+
 # Linux headers same as kernel, a 3.4 series
 BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_3_4=y