diff --git a/src/sage/modules/vector_rational_dense.pyx b/src/sage/modules/vector_rational_dense.pyx
index 6745547bdc7..567fe6dac53 100644
--- a/src/sage/modules/vector_rational_dense.pyx
+++ b/src/sage/modules/vector_rational_dense.pyx
@@ -140,12 +140,10 @@ cdef class Vector_rational_dense(free_module_element.FreeModuleElement):
     def __dealloc__(self):
         cdef Py_ssize_t i
         if self._entries:
-            sig_on()
+            # Do *not* use sig_on() here, since __dealloc__
+            # cannot raise exceptions!
             for i from 0 <= i < self._degree:
-                #print "clearing gmp's entry %s"%i
                 mpq_clear(self._entries[i])
-            sig_off()
-            #print "clearing python entries"
             sage_free(self._entries)
 
     cdef int _cmp_c_impl(left, Element right) except -2:
diff --git a/src/sage/sat/solvers/cryptominisat/cryptominisat.pyx b/src/sage/sat/solvers/cryptominisat/cryptominisat.pyx
index 4d938a7b536..c93a3bdf41f 100644
--- a/src/sage/sat/solvers/cryptominisat/cryptominisat.pyx
+++ b/src/sage/sat/solvers/cryptominisat/cryptominisat.pyx
@@ -112,9 +112,7 @@ cdef class CryptoMiniSat(SatSolver):
             sage: cms = CryptoMiniSat()                      # optional - cryptominisat
             sage: del cms                                    # optional - cryptominisat
         """
-        sig_on()
         del self
-        sig_off()
 
     def __repr__(self):
          """