diff --git a/runtime/starpu/control/runtime_tags.c b/runtime/starpu/control/runtime_tags.c
index 3030d12c5a346dc9cdcebe5f95445b5fa6b2082e..3f10ddbc980b7d573b829c1ebe1ac2bc8d490814 100644
--- a/runtime/starpu/control/runtime_tags.c
+++ b/runtime/starpu/control/runtime_tags.c
@@ -179,6 +179,15 @@ chameleon_starpu_tag_release( int64_t min )
         current = current->next;
     }
 
+    if ( current == NULL ) {
+#if defined(CHAMELEON_DEBUG_STARPU)
+        fprintf( stderr, "chameleon_starpu_tag: FAILED to release [%ld,...] no set registered with this min value\n",
+                 min );
+#endif
+
+        return;
+    }
+
     assert( current != NULL );
     assert( current->min == min );
 
@@ -212,7 +221,7 @@ chameleon_starpu_tag_release( int64_t min )
  * @retval TODO
  *
  ******************************************************************************/
-int
+void
 chameleon_starpu_tag_init( ) {
     return CHAMELEON_SUCCESS;
 }
diff --git a/runtime/starpu/include/chameleon_starpu.h.in b/runtime/starpu/include/chameleon_starpu.h.in
index d967fac54efab35815205367f4b65fe082b48366..f98a29b177a5febd622385ca75c59a467a7fe5db 100644
--- a/runtime/starpu/include/chameleon_starpu.h.in
+++ b/runtime/starpu/include/chameleon_starpu.h.in
@@ -152,7 +152,7 @@ typedef struct starpu_option_request_s {
 /**
  * MPI tag management
  */
-int     chameleon_starpu_tag_init( );
+void    chameleon_starpu_tag_init( );
 int64_t chameleon_starpu_tag_book( int64_t nbtags );
 void    chameleon_starpu_tag_release( int64_t min );
 
diff --git a/testing/parameters.c b/testing/parameters.c
index 8f6e1f4adb390c137411f0abf2222685b56b2415..f8b936946e77cc610b90adbb88fc34fdc76bc25a 100644
--- a/testing/parameters.c
+++ b/testing/parameters.c
@@ -305,7 +305,13 @@ void
 parameters_read( parameter_t *param,
                  const char  *values )
 {
-    int range = (values != NULL) && ( strchr( values, ':' ) != NULL );
+    int range;
+
+    if ( values == NULL ) {
+        fprintf( stderr, "Error passing NULL parameter to read\n" );
+        exit(EXIT_FAILURE);
+    }
+    range = (values != NULL) && ( strchr( values, ':' ) != NULL );
 
     /* If we have a ranged of integer values */
     if ( range )