diff --git a/src/QS.cpp b/src/QS.cpp
index 3fbe8bf..41f7188 100644
--- a/src/QS.cpp
+++ b/src/QS.cpp
@@ -1553,6 +1553,7 @@ void mainRoutine(unsigned long Mdiv2, mpz_t n, unsigned long multiplier)
            gmp_printf("%Zd\n",temp);
         }
     }
+    free(nullrows);
     mpz_clear(factor);
     return;
 }
@@ -1644,21 +1645,43 @@ int main(int argc, char *argv[])
 #endif
     if (tmp_dir == NULL) tmp_dir = "./";
     char * delfile;
+    char * unique_name;
     
-    delfile = get_filename(tmp_dir,unique_filename("comb"));
+    unique_name = unique_filename("comb");
+    delfile = get_filename(tmp_dir,unique_name);
     remove(delfile);
-    delfile = get_filename(tmp_dir,unique_filename("frels"));
+    free(delfile);
+    free(unique_name);
+    unique_name = unique_filename("frels");
+    delfile = get_filename(tmp_dir,unique_name);
     remove(delfile);
-    delfile = get_filename(tmp_dir,unique_filename("flprels"));
+    free(delfile);
+    free(unique_name);
+    unique_name = unique_filename("flprels");
+    delfile = get_filename(tmp_dir,unique_name);
     remove(delfile);
-    delfile = get_filename(tmp_dir,unique_filename("lpnew"));
+    free(delfile);
+    free(unique_name);
+    unique_name = unique_filename("lpnew");
+    delfile = get_filename(tmp_dir,unique_name);
     remove(delfile);
-    delfile = get_filename(tmp_dir,unique_filename("rels"));
+    free(delfile);
+    free(unique_name);
+    unique_name = unique_filename("rels");
+    delfile = get_filename(tmp_dir,unique_name);
     remove(delfile);
-    delfile = get_filename(tmp_dir,unique_filename("fnew"));
+    free(delfile);
+    free(unique_name);
+    unique_name = unique_filename("fnew");
+    delfile = get_filename(tmp_dir,unique_name);
     remove(delfile);
-    delfile = get_filename(tmp_dir,unique_filename("lprels"));
+    free(delfile);
+    free(unique_name);
+    unique_name = unique_filename("lprels");
+    delfile = get_filename(tmp_dir,unique_name);
     remove(delfile);
+    free(delfile);
+    free(unique_name);
       
     return 0;
 }
diff --git a/src/lprels.cpp b/src/lprels.cpp
index 5b6613e..6a5950e 100644
--- a/src/lprels.cpp
+++ b/src/lprels.cpp
@@ -80,7 +80,11 @@ FILE * flint_fopen(char * name, char * mode)
   char * tmp_dir = getenv("TMPDIR");
 #endif
   if (tmp_dir == NULL) tmp_dir = "./";
-  FILE * temp_file = fopen(get_filename(tmp_dir,unique_filename(name)),mode);
+  char * unique_name = unique_filename(name);
+  char * file_name = get_filename(tmp_dir,unique_name);
+  FILE * temp_file = fopen(file_name,mode);
+  free(file_name);
+  free(unique_name);
   if (!temp_file)
   {
      printf("Unable to open temporary file\n");
@@ -497,10 +501,14 @@ long mergesort_lp_file(char *REL_str, char *NEW_str, char *TMP_str, FILE *COMB)
   char * tmp_dir = getenv("TMPDIR");
 #endif
   if (tmp_dir == NULL) tmp_dir = "./";
-  char * TMP_name = get_filename(tmp_dir,unique_filename(TMP_str));
-  char * REL_name = get_filename(tmp_dir,unique_filename(REL_str));
+  char * TMP_unique = unique_filename(TMP_str);
+  char * REL_unique = unique_filename(REL_str);
+  char * TMP_name = get_filename(tmp_dir,TMP_unique);
+  char * REL_name = get_filename(tmp_dir,REL_unique);
   FILE * TMP = fopen(TMP_name,"w");
   FILE * REL = fopen(REL_name,"r");
+  free(REL_unique);
+  free(TMP_unique);
   if ((!TMP) || (!REL))
   {
      printf("Unable to open temporary file\n");
@@ -516,6 +524,8 @@ long mergesort_lp_file(char *REL_str, char *NEW_str, char *TMP_str, FILE *COMB)
      printf("Cannot rename file %s to %s", TMP_str, REL_str);
      abort();
   } 
+  free(REL_name);
+  free(TMP_name);
   return tp;
 }