diff --git mlibc-clean/abis/linux/in.h mlibc-workdir/abis/linux/in.h
index 87bc25f..d7370d0 100644
--- mlibc-clean/abis/linux/in.h
+++ mlibc-workdir/abis/linux/in.h
@@ -109,6 +109,9 @@ struct group_source_req {
 
 #define IPPORT_RESERVED 1024
 
+#define IP_MULTICAST_TTL 33
+#define IPV6_MULTICAST_HOPS 18
+
 #define IPPROTO_IP       0
 #define IPPROTO_HOPOPTS  0
 #define IPPROTO_ICMP     1
diff --git mlibc-clean/options/ansi/generic/environment.cpp mlibc-workdir/options/ansi/generic/environment.cpp
index 5625592..36b42ee 100644
--- mlibc-clean/options/ansi/generic/environment.cpp
+++ mlibc-workdir/options/ansi/generic/environment.cpp
@@ -111,8 +111,10 @@ namespace mlibc {
 int putenv(char *string) {
 	frg::string_view view{string};
 	size_t s = view.find_first('=');
-	if(s == size_t(-1))
-		__ensure(!"Environment strings need to contain an equals sign");
+	if(s == size_t(-1)) {
+		unsetenv(string);
+		return 0;
+	}
 
 	update_vector();
 	assign_variable(view.sub_string(0, s), string, true);
diff --git mlibc-clean/options/ansi/generic/string-stubs.cpp mlibc-workdir/options/ansi/generic/string-stubs.cpp
index 8defd0e..d6cb65b 100644
--- mlibc-clean/options/ansi/generic/string-stubs.cpp
+++ mlibc-workdir/options/ansi/generic/string-stubs.cpp
@@ -406,7 +406,6 @@ char *strerror(int e) {
 	case ENOPROTOOPT: s = "Protocol not available (ENOPROTOOPT)"; break;
 	case ENOTEMPTY: s = "Directory not empty (ENOTEMPTY)"; break;
 	case ENOTRECOVERABLE: s = "Sate not recoverable (ENOTRECOVERABLE)"; break;
-	case ENOTSUP: s = "Operation not supported (ENOTSUP)"; break;
 	case ENOTTY: s = "Inappropriate ioctl for device (ENOTTY)"; break;
 	case EOVERFLOW: s = "Value too large for defined datatype (EOVERFLOW)"; break;
 #if EOPNOTSUPP != ENOTSUP
diff --git mlibc-clean/options/crypt/generic/crypt-stubs.cpp mlibc-workdir/options/crypt/generic/crypt-stubs.cpp
index 65e0d23..95b060c 100644
--- mlibc-clean/options/crypt/generic/crypt-stubs.cpp
+++ mlibc-workdir/options/crypt/generic/crypt-stubs.cpp
@@ -1,7 +1,8 @@
 #include <crypt.h>
 #include <bits/ensure.h>
+#include <string.h>
 
-char *crypt(const char *, const char *) {
+char *crypt(const char *passwd, const char *) {
 	__ensure(!"Not implemented");
 	__builtin_unreachable();
 }
diff --git mlibc-clean/options/glibc/generic/execinfo.cpp mlibc-workdir/options/glibc/generic/execinfo.cpp
index 3474615..e034881 100644
--- mlibc-clean/options/glibc/generic/execinfo.cpp
+++ mlibc-workdir/options/glibc/generic/execinfo.cpp
@@ -1,9 +1,10 @@
 #include <execinfo.h>
 #include <bits/ensure.h>
+#include <mlibc/debug.hpp>
 
 int backtrace(void **, int) {
-	__ensure(!"Not implemented");
-	__builtin_unreachable();
+	mlibc::infoLogger() << "libc: backtrace() is not implemented!\n" << frg::endlog;
+	return 0;
 }
 
 char **backtrace_symbols(void *const *, int) {
diff --git mlibc-clean/options/posix/generic/dlfcn-stubs.cpp mlibc-workdir/options/posix/generic/dlfcn-stubs.cpp
index fc34a3b..b1a95a9 100644
--- mlibc-clean/options/posix/generic/dlfcn-stubs.cpp
+++ mlibc-workdir/options/posix/generic/dlfcn-stubs.cpp
@@ -1,4 +1,4 @@
-
+#define _GNU_SOURCE
 #include <bits/ensure.h>
 #include <dlfcn.h>
 
diff --git mlibc-clean/options/posix/generic/unistd-stubs.cpp mlibc-workdir/options/posix/generic/unistd-stubs.cpp
index 444ad22..d1ca86e 100644
--- mlibc-clean/options/posix/generic/unistd-stubs.cpp
+++ mlibc-workdir/options/posix/generic/unistd-stubs.cpp
@@ -484,8 +484,9 @@ int lockf(int fd, int op, off_t size) {
 }
 
 int nice(int) {
-	__ensure(!"Not implemented");
-	__builtin_unreachable();
+	return EPERM;
+	//__ensure(!"Not implemented");
+	//__builtin_unreachable();
 }
 
 long pathconf(const char *, int name) {
diff --git mlibc-clean/options/rtld/generic/main.cpp mlibc-workdir/options/rtld/generic/main.cpp
index 9219ef0..1ff679c 100644
--- mlibc-clean/options/rtld/generic/main.cpp
+++ mlibc-workdir/options/rtld/generic/main.cpp
@@ -17,6 +17,8 @@
 #include "elf.hpp"
 #include "linker.hpp"
 
+#define _GNU_SOURCE
+
 #if __MLIBC_POSIX_OPTION
 #include <dlfcn.h>
 #endif