diff --git a/.gitignore b/.gitignore
index 5543d7a..052804e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -142,6 +142,7 @@ include/openssl/*.h
 !/crypto/compat/arc4random.h
 !/crypto/compat/b_win.c
 !/crypto/compat/explicit_bzero_win.c
+!/crypto/compat/getpagesize.c
 !/crypto/compat/posix_win.c
 !/crypto/compat/bsd_asprintf.c
 !/crypto/compat/inet_pton.c
diff --git a/crypto/CMakeLists.txt b/crypto/CMakeLists.txt
index 47f0077..d7b65e2 100644
--- a/crypto/CMakeLists.txt
+++ b/crypto/CMakeLists.txt
@@ -681,6 +681,10 @@ if(NOT HAVE_ASPRINTF)
 	set(EXTRA_EXPORT ${EXTRA_EXPORT} vasprintf)
 endif()
 
+if(NOT HAVE_GETPAGESIZE)
+	set(CRYPTO_SRC ${CRYPTO_SRC} compat/getpagesize.c)
+endif()
+
 if(NOT HAVE_INET_PTON)
 	set(CRYPTO_SRC ${CRYPTO_SRC} compat/inet_pton.c)
 	set(EXTRA_EXPORT ${EXTRA_EXPORT} inet_pton)
@@ -691,6 +695,11 @@ if(NOT HAVE_REALLOCARRAY)
 	set(EXTRA_EXPORT ${EXTRA_EXPORT} reallocarray)
 endif()
 
+if(NOT HAVE_RECALLOCARRAY)
+	set(CRYPTO_SRC ${CRYPTO_SRC} compat/recallocarray.c)
+	set(EXTRA_EXPORT ${EXTRA_EXPORT} recallocarray)
+endif()
+
 if(NOT HAVE_STRCASECMP)
 	set(CRYPTO_SRC ${CRYPTO_SRC} compat/strcasecmp.c)
 	set(EXTRA_EXPORT ${EXTRA_EXPORT} strcasecmp)
diff --git a/crypto/Makefile.am b/crypto/Makefile.am
index 23aaeac..dc94a8c 100644
--- a/crypto/Makefile.am
+++ b/crypto/Makefile.am
@@ -81,6 +81,10 @@ if !HAVE_ASPRINTF
 libcompat_la_SOURCES += compat/bsd-asprintf.c
 endif
 
+if !HAVE_GETPAGESIZE
+libcompat_la_SOURCES += compat/getpagesize.c
+endif
+
 if !HAVE_INET_PTON
 libcompat_la_SOURCES += compat/inet_pton.c
 endif
@@ -93,6 +97,10 @@ if !HAVE_REALLOCARRAY
 libcompat_la_SOURCES += compat/reallocarray.c
 endif
 
+if !HAVE_RECALLOCARRAY
+libcompat_la_SOURCES += compat/recallocarray.c
+endif
+
 if !HAVE_TIMINGSAFE_MEMCMP
 libcompat_la_SOURCES += compat/timingsafe_memcmp.c
 endif
diff --git a/crypto/compat/getpagesize.c b/crypto/compat/getpagesize.c
new file mode 100644
index 0000000..098efa9
--- /dev/null
+++ b/crypto/compat/getpagesize.c
@@ -0,0 +1,18 @@
+/* $OpenBSD$ */
+
+#include <unistd.h>
+
+#ifdef _MSC_VER
+#include <windows.h>
+#endif
+
+int
+getpagesize(void) {
+#ifdef _MSC_VER
+	SYSTEM_INFO system_info;
+	GetSystemInfo(&system_info);
+	return system_info.dwPageSize;
+#else
+	return sysconf(_SC_PAGESIZE);
+#endif
+}
diff --git a/include/compat/stdlib.h b/include/compat/stdlib.h
index 781be77..11f82ba 100644
--- a/include/compat/stdlib.h
+++ b/include/compat/stdlib.h
@@ -29,6 +29,10 @@ uint32_t arc4random_uniform(uint32_t upper_bound);
 void *reallocarray(void *, size_t, size_t);
 #endif
 
+#ifndef HAVE_RECALLOCARRAY
+void *recallocarray(void *, size_t, size_t, size_t);
+#endif
+
 #ifndef HAVE_STRTONUM
 long long strtonum(const char *nptr, long long minval,
 		long long maxval, const char **errstr);
diff --git a/include/compat/unistd.h b/include/compat/unistd.h
index b37a2f6..d596043 100644
--- a/include/compat/unistd.h
+++ b/include/compat/unistd.h
@@ -39,6 +39,10 @@ int getentropy(void *buf, size_t buflen);
 #endif
 #endif
 
+#ifndef HAVE_GETPAGESIZE
+int getpagesize(void);
+#endif
+
 #define pledge(request, paths) 0
 
 #ifndef HAVE_PIPE2
diff --git a/m4/check-libc.m4 b/m4/check-libc.m4
index 53ffce6..f9ddf73 100644
--- a/m4/check-libc.m4
+++ b/m4/check-libc.m4
@@ -2,15 +2,18 @@ AC_DEFUN([CHECK_LIBC_COMPAT], [
 # Check for libc headers
 AC_CHECK_HEADERS([err.h readpassphrase.h])
 # Check for general libc functions
-AC_CHECK_FUNCS([asprintf inet_ntop inet_pton memmem readpassphrase])
-AC_CHECK_FUNCS([reallocarray strlcat strlcpy strndup strnlen strsep strtonum])
+AC_CHECK_FUNCS([asprintf getpagesize inet_ntop inet_pton memmem readpassphrase])
+AC_CHECK_FUNCS([reallocarray recallocarray])
+AC_CHECK_FUNCS([strlcat strlcpy strndup strnlen strsep strtonum])
 AC_CHECK_FUNCS([timegm _mkgmtime])
 AM_CONDITIONAL([HAVE_ASPRINTF], [test "x$ac_cv_func_asprintf" = xyes])
+AM_CONDITIONAL([HAVE_GETPAGESIZE], [test "x$ac_cv_func_getpagesize" = xyes])
 AM_CONDITIONAL([HAVE_INET_NTOP], [test "x$ac_cv_func_inet_ntop" = xyes])
 AM_CONDITIONAL([HAVE_INET_PTON], [test "x$ac_cv_func_inet_pton" = xyes])
 AM_CONDITIONAL([HAVE_MEMMEM], [test "x$ac_cv_func_memmem" = xyes])
 AM_CONDITIONAL([HAVE_READPASSPHRASE], [test "x$ac_cv_func_readpassphrase" = xyes])
 AM_CONDITIONAL([HAVE_REALLOCARRAY], [test "x$ac_cv_func_reallocarray" = xyes])
+AM_CONDITIONAL([HAVE_RECALLOCARRAY], [test "x$ac_cv_func_recallocarray" = xyes])
 AM_CONDITIONAL([HAVE_STRLCAT], [test "x$ac_cv_func_strlcat" = xyes])
 AM_CONDITIONAL([HAVE_STRLCPY], [test "x$ac_cv_func_strlcpy" = xyes])
 AM_CONDITIONAL([HAVE_STRNDUP], [test "x$ac_cv_func_strndup" = xyes])
@@ -173,6 +176,9 @@ fi
 if test "x$ac_cv_func_reallocarray" = "xno" ; then
 	echo reallocarray >> $crypto_p_sym
 fi
+if test "x$ac_cv_func_recallocarray" = "xno" ; then
+	echo recallocarray >> $crypto_p_sym
+fi
 if test "x$ac_cv_func_strlcat" = "xno" ; then
 	echo strlcat >> $crypto_p_sym
 fi
diff --git a/update.sh b/update.sh
index dbb9b60..6fb1da7 100755
--- a/update.sh
+++ b/update.sh
@@ -78,6 +78,7 @@ for i in crypto/compat libtls-standalone/compat; do
 	    $libc_src/crypt/chacha_private.h \
 	    $libc_src/net/inet_pton.c \
 	    $libc_src/stdlib/reallocarray.c \
+	    $libc_src/stdlib/recallocarray.c \
 	    $libc_src/string/explicit_bzero.c \
 	    $libc_src/string/strcasecmp.c \
 	    $libc_src/string/strlcpy.c \