diff --git a/Envelope_3/test/Envelope_3/spheres_test.cpp b/Envelope_3/test/Envelope_3/spheres_test.cpp
index 225a1bbf5a8..62d5ebe283b 100644
--- a/Envelope_3/test/Envelope_3/spheres_test.cpp
+++ b/Envelope_3/test/Envelope_3/spheres_test.cpp
@@ -49,7 +49,7 @@ bool test_one_file(std::ifstream& inp)
   Envelope_test lu_alg_test;
   std::vector<Xy_monotone_surface_3> surfaces;
 
-  int spheres_num;
+  int spheres_num = 0;
   inp >> spheres_num;
   Rat_point_3 a;
   Rational sr;
diff --git a/Envelope_3/test/Envelope_3/triangles_test.cpp b/Envelope_3/test/Envelope_3/triangles_test.cpp
index ada7ec10cb9..dbf71da40e7 100644
--- a/Envelope_3/test/Envelope_3/triangles_test.cpp
+++ b/Envelope_3/test/Envelope_3/triangles_test.cpp
@@ -42,7 +42,7 @@ bool test_one_file(std::ifstream& inp)
   Traits_3 traits;
   std::vector<Surface_3> triangles;
   
-  int triangles_num;
+  int triangles_num = 0;
   inp >> triangles_num;
   std::cout << "number of triangles to read: " << triangles_num << std::endl;
   Point_3 a,b,c;