Keep an object from being deallocated while pointers to or into it are in use.
Fixes warnings like these:

longrat.cc: In function 'nlMapC(snumber*, n_Procs_s*, n_Procs_s*)':
longrat.cc:599:13: warning: dangling pointer to an unnamed temporary may be used [-Wdangling-pointer=]
  599 |   e=(*f)[0]._mp_exp-size;
      |     ~~~~~~~~^~~~~~~
longrat.cc:573:40: note: unnamed temporary defined here
  573 |   mpf_t *f = ((gmp_complex*)from)->real()._mpfp();
      |              ~~~~~~~~~~~~~~~~~~~~~~~~~~^~
longrat.cc:581:8: warning: using dangling pointer 'size_113' to an unnamed temporary [-Wdangling-pointer=]
  581 |   size = (*f)[0]._mp_size;
      |   ~~~~~^~~~~~~~~~~~~~~~~~
longrat.cc:573:40: note: unnamed temporary defined here
  573 |   mpf_t *f = ((gmp_complex*)from)->real()._mpfp();
      |              ~~~~~~~~~~~~~~~~~~~~~~~~~~^~
longrat.cc:592:6: warning: dangling pointer 'qp_115' to an unnamed temporary may be used [-Wdangling-pointer=]
  592 |   qp = (*f)[0]._mp_d;
      |   ~~~^~~~~~~~~~~~~~~
longrat.cc:573:40: note: unnamed temporary defined here
  573 |   mpf_t *f = ((gmp_complex*)from)->real()._mpfp();
      |              ~~~~~~~~~~~~~~~~~~~~~~~~~~^~

--- Singular-Release-4-2-1p3/factory/cfModGcd.cc.orig	2021-12-17 11:35:18.000000000 -0700
+++ Singular-Release-4-2-1p3/factory/cfModGcd.cc	2022-07-25 14:53:41.944360644 -0600
@@ -1825,7 +1825,6 @@ gaussianElimFq (CFMatrix& M, CFArray& L,
   #else
   factoryError("NTL/FLINT missing: gaussianElimFq");
   #endif
-  delete N;
 
   M= (*N) (1, M.rows(), 1, M.columns());
   L= CFArray (M.rows());
--- Singular-Release-4-2-1p3/libpolys/coeffs/longrat.cc.orig	2021-12-17 11:35:18.000000000 -0700
+++ Singular-Release-4-2-1p3/libpolys/coeffs/longrat.cc	2022-07-25 10:59:58.720085578 -0600
@@ -570,7 +570,8 @@ static number nlMapC(number from, const
     return INT_TO_SR(0);
   }
       
-  mpf_t *f = ((gmp_complex*)from)->real()._mpfp();
+  gmp_float gfl = ((gmp_complex*)from)->real();
+  mpf_t *f = gfl._mpfp();
 
   number res;
   mpz_ptr dest,ndest;
--- Singular-Release-4-2-1p3/Singular/countedref.cc.orig	2021-12-17 11:35:18.000000000 -0700
+++ Singular-Release-4-2-1p3/Singular/countedref.cc	2022-07-25 14:51:02.519890787 -0600
@@ -317,13 +317,17 @@ public:
   /// Recover the actual object from Singular interpreter object
   static self cast(leftv arg) {
     assume(arg != NULL); assume(is_ref(arg));
-    return self::cast(arg->Data());
+    auto d = arg->Data();
+    return self::cast(d);
   }
 
   /// If necessary dereference.
   static BOOLEAN resolve(leftv arg) {
     assume(arg != NULL);
-    while (is_ref(arg)) { if(CountedRef::cast(arg).dereference(arg)) return TRUE; };
+    while (is_ref(arg)) {
+      CountedRef ref = CountedRef::cast(arg);
+      if (ref.dereference(arg)) return TRUE;
+    }
     return (arg->next != NULL) && resolve(arg->next);
   }
 
@@ -369,8 +373,9 @@ char* countedref_String(blackbox */*b*/,
 /// blackbox support - copy element
 void* countedref_Copy(blackbox*/*b*/, void* ptr)
 {
-  if (ptr) return CountedRef::cast(ptr).outcast();
-  return NULL;
+  if (!ptr) return NULL;
+  CountedRef ref = CountedRef::cast(ptr);
+  return ref.outcast();
 }
 
 /// blackbox support - assign element
@@ -383,12 +388,16 @@ BOOLEAN countedref_Assign(leftv result,
   }
 
   // Case: copy reference
-  if (result->Typ() == arg->Typ())
-    return CountedRef::cast(arg).outcast(result);
+  if (result->Typ() == arg->Typ()) {
+    CountedRef ref = CountedRef::cast(arg);
+    return ref.outcast(result);
+  }
 
   // Case: new reference
-  if ((arg->rtyp == IDHDL) || CountedRef::is_ref(arg))
-    return CountedRef(arg).outcast(result);
+  if ((arg->rtyp == IDHDL) || CountedRef::is_ref(arg)) {
+    CountedRef ref(arg);
+    return ref.outcast(result);
+  }
 
   WerrorS("Can only take reference from identifier");
   return TRUE;
@@ -483,7 +492,10 @@ BOOLEAN countedref_Op3(int op, leftv res
 /// blackbox support - destruction
 void countedref_destroy(blackbox */*b*/, void* ptr)
 {
-  if (ptr) CountedRef::cast(ptr).destruct();
+  if (ptr) {
+    CountedRef ref = CountedRef::cast(ptr);
+    ref.destruct();
+  }
 }
 
 
@@ -539,7 +551,8 @@ public:
 /// Blackbox support - generate initialized, but all-zero - shared data
 void* countedref_InitShared(blackbox*)
 {
-  return CountedRefShared().outcast();
+  auto ref = CountedRefShared();
+  return ref.outcast();
 }
 
 /// Blackbox support - unary operation for shared data
@@ -656,23 +669,31 @@ BOOLEAN countedref_AssignShared(leftv re
   /// Case: new reference to already shared data
   if (result->Typ() == arg->Typ())
   {
-    if (result->Data() != NULL)
-      CountedRefShared::cast(result).destruct();
-    return CountedRefShared::cast(arg).outcast(result);
+    if (result->Data() != NULL) {
+      CountedRefShared ref = CountedRefShared::cast(result);
+      ref.destruct();
+    }
+    CountedRefShared ref = CountedRefShared::cast(arg);
+    return ref.outcast(result);
   }
   if(CountedRefShared::cast(result).unassigned())
   {
-    return CountedRefShared::cast(result).assign(result, arg);
+    CountedRefShared ref = CountedRefShared::cast(result);
+    return ref.assign(result, arg);
   }
 
   /// Case: new shared data
-  return CountedRefShared(arg).outcast(result);
+  CountedRefShared ref(arg);
+  return ref.outcast(result);
 }
 
 /// blackbox support - destruction
 void countedref_destroyShared(blackbox */*b*/, void* ptr)
 {
-  if (ptr) CountedRefShared::cast(ptr).destruct();
+  if (ptr) {
+    CountedRefShared ref = CountedRefShared::cast(ptr);
+    ref.destruct();
+  }
 }