diff --git a/package/fscryptctl/fscryptctl.mk b/package/fscryptctl/fscryptctl.mk
index 154af4d29f..0546f67a1f 100644
--- a/package/fscryptctl/fscryptctl.mk
+++ b/package/fscryptctl/fscryptctl.mk
@@ -10,7 +10,8 @@ FSCRYPTCTL_LICENSE = Apache-2.0
 FSCRYPTCTL_LICENSE_FILES = LICENSE
 
 define FSCRYPTCTL_BUILD_CMDS
-	$(MAKE) -C $(@D) $(TARGET_CONFIGURE_OPTS) fscryptctl
+	$(MAKE) -C $(@D) $(TARGET_CONFIGURE_OPTS) \
+		CFLAGS="$(TARGET_CFLAGS) -std=c99" fscryptctl
 endef
 
 define FSCRYPTCTL_INSTALL_TARGET_CMDS