Fix the assertion to be callable from parallel context

Author: byjtew

include/graphblas/omp/config.hpp

@@ -79,6 +79,15 @@ namespace grb {
 					return ret;
 				}
 
+				/**
+				 * @returns The maximum number of threads reported by OpenMP.
+				 *
+				 * This function can be called from any context.
+				 */
+				static size_t maxThreads() {
+					return omp_get_max_threads();
+				}
+
 				/**
 				 * @returns The number of threads in the current OpenMP parallel section.
 				 *

include/graphblas/reference/vector.hpp

@@ -1275,7 +1275,12 @@ namespace grb {
 			template< typename D, typename C >
 			inline C & getCoordinates( Vector< D, reference, C > &x ) noexcept {
 #ifdef _H_GRB_REFERENCE_OMP_VECTOR
-				assert( x._coordinates.requiredThreadsForUpdate() == config::OMP::threads() );
+				if( x._coordinates.requiredThreadsForUpdate() != config::OMP::maxThreads() ) {
+					#pragma omp critical
+						std::cerr << "   " << x._coordinates.requiredThreadsForUpdate()
+							<< " != " << config::OMP::maxThreads() << "\n";
+				}
+				assert( x._coordinates.requiredThreadsForUpdate() == config::OMP::maxThreads() );
 #endif
 				return x._coordinates;
 			}