Hello, I stumbled about the current cvs HEAD version of exception.hpp, where I found one remaining throw under *_NO_EXCEPTIONS conditions in "singular". Here the proposed fix: Index: exception.hpp =================================================================== RCS file: /cvsroot/boost/boost/boost/numeric/ublas/exception.hpp,v retrieving revision 1.19 diff -u -r1.19 exception.hpp --- exception.hpp 2 Feb 2006 19:27:23 -0000 1.19 +++ exception.hpp 13 Nov 2006 18:54:27 -0000 @@ -175,7 +175,6 @@ explicit singular (const char *) {} void raise () { - throw *this; std::abort (); } #endif I also would like to recommend, that the current exception text of struct non_real should be changed as follows (The prefix "exception:" seems redundant): Index: exception.hpp =================================================================== RCS file: /cvsroot/boost/boost/boost/numeric/ublas/exception.hpp,v retrieving revision 1.19 diff -u -r1.19 exception.hpp --- exception.hpp 2 Feb 2006 19:27:23 -0000 1.19 +++ exception.hpp 13 Nov 2006 19:01:45 -0000 @@ -185,7 +185,7 @@ #if ! defined (BOOST_NO_EXCEPTIONS) && ! defined (BOOST_UBLAS_NO_EXCEPTIONS) // Inherit from standard exceptions as requested during review. : public std::domain_error { - explicit non_real (const char *s = "exception: non real") : + explicit non_real (const char *s = "non real") : std::domain_error (s) {} void raise () { throw *this; Greetings from Bremen, Daniel Krügler