diff --git a/src/t8_cmesh.h b/src/t8_cmesh.h
index 41228d5b2a..53c9810707 100644
--- a/src/t8_cmesh.h
+++ b/src/t8_cmesh.h
@@ -96,7 +96,7 @@ t8_cmesh_is_committed (const t8_cmesh_t cmesh);
  * \param [in] cmesh            This cmesh is examined.
  * \return                      True if the geometry of the cmesh is valid.
  */
-bool
+int
 t8_cmesh_validate_geometry (const t8_cmesh_t cmesh);
 
 /** After a cmesh is committed, check whether all trees in a cmesh do have positive volume.
@@ -107,7 +107,7 @@ t8_cmesh_validate_geometry (const t8_cmesh_t cmesh);
  *                              was called, do have positive geometric volume.
  *                              False otherwise.
  */
-bool
+int
 t8_cmesh_no_negative_volume (t8_cmesh_t cmesh);
 #endif
 
diff --git a/src/t8_cmesh/t8_cmesh.cxx b/src/t8_cmesh/t8_cmesh.cxx
index c01ee35014..f3ab489374 100644
--- a/src/t8_cmesh/t8_cmesh.cxx
+++ b/src/t8_cmesh/t8_cmesh.cxx
@@ -123,7 +123,7 @@ t8_cmesh_is_committed (const t8_cmesh_t cmesh)
 }
 
 #ifdef T8_ENABLE_DEBUG
-bool
+int
 t8_cmesh_validate_geometry (const t8_cmesh_t cmesh)
 {
   /* Geometry handler is not constructed yet */
@@ -532,7 +532,7 @@ t8_cmesh_tree_vertices_negative_volume (const t8_eclass_t eclass, const double *
  * Returns true if all trees have positive volume. Returns also true if no geometries are
  * registered yet, since the volume computation depends on the used geometry.
  */
-bool
+int
 t8_cmesh_no_negative_volume (t8_cmesh_t cmesh)
 {
   bool res = false;
diff --git a/src/t8_geometry/t8_geometry.cxx b/src/t8_geometry/t8_geometry.cxx
index bdd4111a19..33396a962b 100644
--- a/src/t8_geometry/t8_geometry.cxx
+++ b/src/t8_geometry/t8_geometry.cxx
@@ -64,7 +64,7 @@ t8_geometry_get_type (t8_cmesh_t cmesh, t8_gloidx_t gtreeid)
   return cmesh->geometry_handler->get_tree_geometry_type (cmesh, gtreeid);
 }
 
-bool
+int
 t8_geometry_tree_negative_volume (const t8_cmesh_t cmesh, const t8_gloidx_t gtreeid)
 {
   return cmesh->geometry_handler->tree_negative_volume (cmesh, gtreeid);
diff --git a/src/t8_geometry/t8_geometry.h b/src/t8_geometry/t8_geometry.h
index bb10437ba7..0edc3e5a96 100644
--- a/src/t8_geometry/t8_geometry.h
+++ b/src/t8_geometry/t8_geometry.h
@@ -30,7 +30,6 @@
 
 #include <t8.h>
 #include <t8_refcount.h>
-#include <stdbool.h>
 
 /** This enumeration contains all possible geometries. */
 typedef enum t8_geometry_type {
@@ -109,7 +108,7 @@ t8_geometry_get_type (t8_cmesh_t cmesh, t8_gloidx_t gtreeid);
  * \param[in] gtreeid     The global id of the tree
  * \return                True if the tree with id \ref gtreeid has a negative volume. False otherwise.  
  */
-bool
+int
 t8_geometry_tree_negative_volume (const t8_cmesh_t cmesh, const t8_gloidx_t gtreeid);
 
 T8_EXTERN_C_END ();
diff --git a/src/t8_geometry/t8_geometry_implementations/t8_geometry_analytic.h b/src/t8_geometry/t8_geometry_implementations/t8_geometry_analytic.h
index c97ab843be..1be03e18ff 100644
--- a/src/t8_geometry/t8_geometry_implementations/t8_geometry_analytic.h
+++ b/src/t8_geometry/t8_geometry_implementations/t8_geometry_analytic.h
@@ -69,7 +69,7 @@ typedef void (*t8_geom_load_tree_data_fn) (t8_cmesh_t cmesh, t8_gloidx_t gtreeid
 /**
  * Definition for the negative volume function.
  */
-typedef bool (*t8_geom_tree_negative_volume_fn) ();
+typedef int (*t8_geom_tree_negative_volume_fn) ();
 
 T8_EXTERN_C_BEGIN ();