diff --git a/Makefile.am b/Makefile.am
index 55db2398..a3f265ed 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -157,7 +157,7 @@ libscrypt_sse2_la_CFLAGS=`. ./cpusupport-config.h; echo $${CFLAGS_X86_SSE2}`
 noinst_LTLIBRARIES+=	libscrypt_memlimit.la
 libscrypt_memlimit_la_SOURCES=	lib-platform/util/memlimit.c	\
 				lib-platform/util/memlimit.h
-libscrypt_memlimit_la_CFLAGS=-U_POSIX_C_SOURCE -U_XOPEN_SOURCE
+libscrypt_memlimit_la_CFLAGS=`. ./apisupport-config.h; echo $${CFLAGS_NONPOSIX_MEMLIMIT}`
 
 # Install libscrypt-kdf?
 if LIBSCRYPT_KDF
diff --git a/libcperciva/apisupport/Build/apisupport-NONPOSIX-MEMLIMIT.c b/libcperciva/apisupport/Build/apisupport-NONPOSIX-MEMLIMIT.c
new file mode 100644
index 00000000..d585ab21
--- /dev/null
+++ b/libcperciva/apisupport/Build/apisupport-NONPOSIX-MEMLIMIT.c
@@ -0,0 +1,19 @@
+#include "platform.h"
+
+#ifdef HAVE_SYS_PARAM_H
+#include <sys/param.h>
+#endif
+#ifdef HAVE_SYS_SYSCTL_H
+#include <sys/sysctl.h>
+#endif
+#ifdef HAVE_SYS_SYSINFO_H
+#include <sys/sysinfo.h>
+#endif
+
+int
+main(void)
+{
+
+	/* Success! */
+	return (0);
+}
diff --git a/libcperciva/apisupport/Build/apisupport.sh b/libcperciva/apisupport/Build/apisupport.sh
index 4b11c6a0..aedd5662 100755
--- a/libcperciva/apisupport/Build/apisupport.sh
+++ b/libcperciva/apisupport/Build/apisupport.sh
@@ -74,6 +74,9 @@ fi
 feature NONPOSIX SETGROUPS "" ""			\
 	"-U_POSIX_C_SOURCE -U_XOPEN_SOURCE"		\
 	"-U_POSIX_C_SOURCE -U_XOPEN_SOURCE -Wno-reserved-id-macro"
+feature NONPOSIX MEMLIMIT "" ""				\
+	"-U_POSIX_C_SOURCE -U_XOPEN_SOURCE"		\
+	"-U_POSIX_C_SOURCE -U_XOPEN_SOURCE -Wno-reserved-id-macro"
 
 # Detect how to compile libssl and libcrypto code.
 feature LIBSSL HOST_NAME "-lssl" ""			\