bobcat expects the GNU variant of strerror_r, while musl only provides the
XSI variant with incompatible return type, leading to a compilation error.
As musl strerror() is re-entrant anyway, just use that instead.
--- a/exception/errnodescr.cc
+++ b/exception/errnodescr.cc
@@ -7,16 +7,7 @@
 {
     if (errno != 0)
     {
-        char *buffer = new char[Exception::STRERROR_BUFSIZE];
-
-        if (char *cp = strerror_r(errno, buffer, Exception::STRERROR_BUFSIZE))
-            out << cp;
-        else
-        {
-            out << "internal error: strerror_r failed with errno = " << errno;
-        }
-
-        delete[] buffer;
+        out << strerror(errno);
     }
 
     return out;