[Build] Fix compilation on gcc 4.9.2

src/spatial-solving/fixedpointiterator.cc

@@ -83,7 +83,12 @@ FixedPointIterator<Factory, Updaters, ErrorNorm>::run(
 
   updaters.rate_->postProcess(velocityIterate);
 
-  return { fixedPointIteration, multigridIterations };
+  // Cannot use return { fixedPointIteration, multigridIterations };
+  // with gcc 4.9.2, see also http://stackoverflow.com/a/37777814/179927
+  FixedPointIterationCounter ret;
+  ret.iterations = fixedPointIteration;
+  ret.multigridIterations = multigridIterations;
+  return ret;
 }
 
 std::ostream &operator<<(std::ostream &stream,