Force use of single-thread in Problem::Evaluate() without OpenMP.
- Ensure that, as in the preprocessor, we force num_threads to be 1
if Ceres was compiled without OpenMP to prevent a CHECK() failure
in internal code.
Change-Id: I49d7bdeff81e5bb24aaaa3945018d9d012cd9df9
diff --git a/internal/ceres/problem_impl.cc b/internal/ceres/problem_impl.cc
index 1c76ea6..1a048e5 100644
--- a/internal/ceres/problem_impl.cc
+++ b/internal/ceres/problem_impl.cc
@@ -731,7 +731,15 @@
// the Evaluator decides the storage for the Jacobian based on the
// type of linear solver being used.
evaluator_options.linear_solver_type = SPARSE_NORMAL_CHOLESKY;
+#ifndef CERES_USE_OPENMP
+ LOG_IF(WARNING, evaluate_options.num_threads > 1)
+ << "OpenMP support is not compiled into this binary; "
+ << "only evaluate_options.num_threads = 1 is supported. Switching "
+ << "to single threaded mode.";
+ evaluator_options.num_threads = 1;
+#else
evaluator_options.num_threads = evaluate_options.num_threads;
+#endif // CERES_USE_OPENMP
string error;
scoped_ptr<Evaluator> evaluator(
