See below for the copyright status on all code included in musl:
The TRE regular expression implementation (src/regex/reg* and
-src/regex/tre*) is Copyright © 2001-2006 Ville Laurikari and licensed
-under the terms of the GNU LGPL version 2.1 or later. The included
-version was heavily modified in Spring 2006 by Rich Felker in the
-interests of size, simplicity, and namespace cleanliness.
-
-The math library code (src/math/* and src/complex/*) is derived mostly
-from FreeBSD and OpenBSD. Copyright information is included in the
-comments in the individual files, all of which are licensed under
-extremely permissive terms compatible with the GNU LGPL.
+src/regex/tre*) is Copyright © 2001-2008 Ville Laurikari and licensed
+under a 2-clause BSD license (license text in the source files). The
+included version has been heavily modified by Rich Felker in 2012, in
+the interests of size, simplicity, and namespace cleanliness.
+
+Most of the math library code (src/math/* and src/complex/*) is
+Copyright © 1993,2004 Sun Microsystems or
+Copyright © 2003-2011 David Schultz or
+Copyright © 2003-2009 Steven G. Kargl or
+Copyright © 2003-2009 Bruce D. Evans or
+Copyright © 2008 Stephen L. Moshier
+and labelled as such. All have been licensed under extremely
+permissive terms which are compatible with the GNU LGPL. See the
+comments in the individual files for details.
The implementation of DES for crypt (src/misc/crypt.c) is Copyright ©
1994 David Burren. It is licensed under a BSD license compatible with