diff --git a/include/errno.h b/include/errno.h
new file mode 100644
index 0000000..e950c67
--- /dev/null
+++ b/include/errno.h
@@ -0,0 +1,3 @@
+#define EDOM 1
+#define ERANGE 2
+#define EILSEQ 3
\ No newline at end of file
diff --git a/include/float.h b/include/float.h
new file mode 100644
index 0000000..75d19e0
--- /dev/null
+++ b/include/float.h
@@ -0,0 +1,33 @@
+#define FLT_RADIX 2
+#define FLT_ROUNDS -1
+#define FLT_EVAL_METHOD -1
+#define DECIMAL_DIG 21
+#define FLT_MANT_DIG 24
+#define FLT_EPSILON 1.19209290E-07f
+#define FLT_DIG 6
+#define FLT_MIN_EXP (-125)
+#define FLT_MIN 1.17549435E-38f
+#define FLT_MIN_10_EXP (-37)
+#define FLT_MAX_EXP 128
+#define FLT_MAX 3.40282347E+38F
+#define FLT_MAX_10_EXP 38
+
+#define DBL_MANT_DIG 53
+#define DBL_EPSILON 2.2204460492503131E-16
+#define DBL_DIG 15
+#define DBL_MIN_EXP (-1021)
+#define DBL_MIN 2.2250738585072014E-308
+#define DBL_MIN_10_EXP (-307)
+#define DBL_MAX_EXP 1024
+#define DBL_MAX 1.7976931348623157E+308
+#define DBL_MAX_10_EXP 308
+
+#define LDBL_MANT_DIG DBL_MANT_DIG
+#define LDBL_EPSILON DBL_EPSILON
+#define LDBL_DIG DBL_DIG
+#define LDBL_MIN_EXP DBL_MIN_EXP
+#define LDBL_MIN DBL_MIN
+#define LDBL_MIN_10_EXP DBL_MIN_10_EXP
+#define LDBL_MAX_EXP DBL_MAX_EXP
+#define LDBL_MAX DBL_MAX
+#define LDBL_MAX_10_EXP DBL_MAX_10_EXP
\ No newline at end of file
diff --git a/include/string.h b/include/string.h
new file mode 100644
index 0000000..d01b314
--- /dev/null
+++ b/include/string.h
@@ -0,0 +1,33 @@
+#ifndef __STRING_H
+#define __STRING_H
+#ifdef __cplusplus
+extern "C" {
+#define NULL nullptr
+#else
+#define NULL 0
+#endif
+typedef unsigned long size_t;
+void *memcpy(void *dest, const void *src, size_t n);
+void *memmove(void *dest, const void *src, size_t n);
+void *memchr(const void *s, int c, size_t n);
+int memcmp(const void *s1, const void *s2, size_t n);
+void *memset(void *, int c, size_t n);
+char *strcat(char *dest, const char *src);
+char *strncat(char *dest, const char *src, size_t n);
+char *strchr(const char *, int c);
+char *strrchr(const char *, int c);
+int strcmp(const char *, const char *);
+int strncmp(const char *, const char *, size_t n);
+char *strcpy(char *dest, const char *src);
+char *strncpy(char *dest, const char *src, size_t n);
+char *strerror(int);
+size_t strlen(const char *);
+size_t strspn(const char *, const char *accept);
+size_t strcspn(const char *, const char *reject);
+char *strpbrk(const char *, const char *accept);
+char *strstr(const char *haystack, const char *needle);
+char *strtok(char *, const char * delim);
+#ifdef __cplusplus
+}
+#endif
+#endif
\ No newline at end of file
diff --git a/include/vararg.h b/include/vararg.h
new file mode 100644
index 0000000..a90c252
--- /dev/null
+++ b/include/vararg.h
@@ -0,0 +1,7 @@
+#ifndef __VARARG_H
+#define __VARARG_H
+typedef __builtin_va_list va_list;
+#define va_start(ap, X) __builtin_va_start(ap, X)
+#define va_arg(ap, type) __builtin_va_arg(ap, type)
+#define va_end(ap) __builtin_va_end(ap)
+#endif
\ No newline at end of file
diff --git a/string/mem.cpp b/string/mem.cpp
new file mode 100644
index 0000000..ea83e81
--- /dev/null
+++ b/string/mem.cpp
@@ -0,0 +1,25 @@
+#include <string.h>
+#include <base.hpp>
+#include <textDISP.hpp>
+extern "C" void __optimized_memcpy_impl(void *dest, const void* src, size_t n);
+extern "C" void *memcpy(void *dest, const void *src, size_t n) {
+    unsigned long p1=(unsigned long)d;
+    unsigned long p2=(unsigned long)s;
+    //If two memory areas overlap, do something nonsensical
+    if(((p1 > p2)&&(p1 < p2+n))||((p1+n > p2)&&(p1+n < p2+n)) {
+        memset(dest, 0, n);
+        err << "Don't use overlapping memory regions with memcpy. Use memmove instead! (Doing sth. nonsensical now.)\n";
+        return dest;
+    }
+    __optimized_memcpy_impl(dest, src, n);
+    return dest;
+}
+extern "C" void __optimized_reverse_memcpy_impl(void *dest, const void* src, size_t n);
+extern "C" void *memmove(void *dest, const void *src, size_t n) {
+    if((unsigned long)dest<(unsigned long)src) {
+        __optimized_memcpy_impl(dest, src, n);
+    } else {
+        __optimized_reverse_memcpy_impl(dest,src,n);
+    }
+    return dest;
+}
\ No newline at end of file