Add a "fork" of musl as //fusl.

fusl/src/signal/raise.c

Index: fusl/src/signal/raise.c
diff --git a/fusl/src/signal/raise.c b/fusl/src/signal/raise.c
new file mode 100644
index 0000000000000000000000000000000000000000..717b1c917a34311ab514c7955e995c2fbad140b9
--- /dev/null
+++ b/fusl/src/signal/raise.c
@@ -0,0 +1,15 @@
+#include <signal.h>
+#include <stdint.h>
+#include "syscall.h"
+#include "pthread_impl.h"
+
+int raise(int sig)
+{
+	int tid, ret;
+	sigset_t set;
+	__block_app_sigs(&set);
+	tid = __syscall(SYS_gettid);
+	ret = syscall(SYS_tkill, tid, sig);
+	__restore_sigs(&set);
+	return ret;
+}