diff --git a/package/kvm-unit-tests/Config.in b/package/kvm-unit-tests/Config.in
index d72c734e78..f704a8e0c3 100644
--- a/package/kvm-unit-tests/Config.in
+++ b/package/kvm-unit-tests/Config.in
@@ -1,8 +1,14 @@
 config BR2_PACKAGE_KVM_UNIT_TESTS
 	bool "kvm-unit-tests"
 	select BR2_HOSTARCH_NEEDS_IA32_COMPILER if BR2_x86_64=y
-	depends on BR2_arm || BR2_i386 || BR2_powerpc64 || \
-		BR2_powerpc64le || BR2_x86_64
+	# on i386 and x86-64, __builtin_reachable is used, so we need
+	# gcc 4.5 at least. on i386, we use the target gcc, while on
+	# x86-64 we use the host gcc (see .mk file for details)
+	depends on BR2_arm || \
+		(BR2_i386 && BR2_TOOLCHAIN_GCC_AT_LEAST_4_5) || \
+		BR2_powerpc64 || \
+		BR2_powerpc64le || \
+		(BR2_x86_64 && BR2_HOST_GCC_AT_LEAST_4_5)
 	help
 	  kvm-unit-tests is a project as old as KVM. As its name
 	  suggests, it's purpose is to provide unit tests for KVM. The