Add SuiteSparse::IsConstrainedApproximateMinimumDegreeOrderingAvailable.
This allows checking for the availability of CAMD without depending
on a preprocessor symbol, which can be the source of subtle bugs
if the file defining that symbol was not included.
Change-Id: I6f1ef91a20baeecf68e8dd467ebe707dde8c5f79
diff --git a/internal/ceres/suitesparse.h b/internal/ceres/suitesparse.h
index 0a7ea97..f27e338 100644
--- a/internal/ceres/suitesparse.h
+++ b/internal/ceres/suitesparse.h
@@ -283,9 +283,21 @@
#else // CERES_NO_SUITESPARSE
-class SuiteSparse {};
typedef void cholmod_factor;
+class SuiteSparse {
+ // Defining this static function even when SuiteSparse is not
+ // available, allows client code to check for the presence of CAMD
+ // without checking for the absence of the CERES_NO_CAMD symbol.
+ //
+ // This is safer because the symbol maybe missing due to a user
+ // accidently not including suitesparse.h in their code when
+ // checking for the symbol.
+ static bool IsConstrainedApproximateMinimumDegreeOrderingAvailable() {
+ return false;
+ }
+};
+
#endif // CERES_NO_SUITESPARSE
#endif // CERES_INTERNAL_SUITESPARSE_H_
