diff --git a/libc/Makefile b/libc/Makefile
index daa68ab3..b891d061 100644
--- a/libc/Makefile
+++ b/libc/Makefile
@@ -184,6 +184,7 @@ stdlib/strtoull.o \
stdlib/strtoul.o \
stdlib/wcstombs.o \
stdlib/wctomb.o \
+string/explicit_bzero.o \
string/ffsll.o \
string/ffsl.o \
string/ffs.o \
diff --git a/libc/include/string.h b/libc/include/string.h
index 3bd814cb..5fbff141 100644
--- a/libc/include/string.h
+++ b/libc/include/string.h
@@ -124,6 +124,7 @@ size_t strxfrm_l(char* __restrict, const char* __restrict, size_t, locale_t);
/* Functions copied from elsewhere. */
#if __USE_SORTIX
+void explicit_bzero(void*, size_t);
int ffsl(long int);
void* memrchr(const void*, int, size_t);
/* TODO: strcasecmp_l */
diff --git a/libc/string/explicit_bzero.cpp b/libc/string/explicit_bzero.cpp
new file mode 100644
index 00000000..a603e027
--- /dev/null
+++ b/libc/string/explicit_bzero.cpp
@@ -0,0 +1,34 @@
+/*******************************************************************************
+
+ Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2014.
+
+ This file is part of the Sortix C Library.
+
+ The Sortix C Library is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or (at your
+ option) any later version.
+
+ The Sortix C Library is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+ License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with the Sortix C Library. If not, see .
+
+ string/explicit_bzero.cpp
+ Initializes a region of memory to a byte value in a manner that is not
+ optimized away by the compiler.
+
+*******************************************************************************/
+
+#include
+
+// TODO: Employ special compiler support to ensure this is not optimized away.
+extern "C" void explicit_bzero(void* dest_ptr, size_t size)
+{
+ volatile unsigned char* dest = (volatile unsigned char*) dest_ptr;
+ for ( size_t i = 0; i < size; i++ )
+ dest[i] = 0;
+}