diff --git a/lang/cpp/src/context.cpp b/lang/cpp/src/context.cpp

index c0a1dc21..e991dbc8 100644

--- a/lang/cpp/src/context.cpp

+++ b/lang/cpp/src/context.cpp

@@ -223,6 +223,7 @@ Context *Context::createForProtocol(Protocol proto)

         }

         break;

     default:

+        gpgme_release(ctx);

         return nullptr;

     }

@@ -273,6 +274,7 @@ std::unique_ptr<Context> Context::createForEngine(Engine eng, Error *error)

         }

         break;

     default:

+        gpgme_release(ctx);

         if (error) {

             *error = Error::fromCode(GPG_ERR_INV_ARG);

         }

diff --git a/lang/cpp/src/data.cpp b/lang/cpp/src/data.cpp

index 7a93cbc2..d08a29db 100644

--- a/lang/cpp/src/data.cpp

+++ b/lang/cpp/src/data.cpp

@@ -249,6 +249,7 @@ std::vector<GpgME::Key> GpgME::Data::toKeys(Protocol proto) const

     }

     if (gpgme_op_keylist_from_data_start (ctx->impl()->ctx, d->data, 0)) {

+        delete ctx;

         return ret;

     }

diff --git a/lang/python/gpgme.i b/lang/python/gpgme.i

index 87371af8..64b88d54 100644

--- a/lang/python/gpgme.i

+++ b/lang/python/gpgme.i

@@ -53,7 +53,7 @@

     {

       encodedInput = PyUnicode_AsUTF8String($input);

       if (encodedInput == NULL)

-        return NULL;

+        SWIG_fail;

       $1 = PyBytes_AsString(encodedInput);

     }

   else if (PyBytes_Check($input))

@@ -62,22 +62,25 @@

     PyErr_Format(PyExc_TypeError,

                  "arg %d: expected str, bytes, or None, got %s",

 		 $argnum, $input->ob_type->tp_name);

-    return NULL;

+    SWIG_fail;

   }

 }

 %typemap(freearg) const char * {

   Py_XDECREF(encodedInput$argnum);

 }

+%typemap(arginit) const char *[] {

+  $1 = NULL;

+}

+

 /* Likewise for a list of strings.  */

-%typemap(in) const char *[] (void *vector = NULL,

-                             size_t size,

+%typemap(in) const char *[] (size_t size,

                              PyObject **pyVector = NULL) {

   /* Check if is a list */

   if (PyList_Check($input)) {

     size_t i, j;

     size = PyList_Size($input);

-    $1 = (char **) (vector = malloc((size+1) * sizeof(char *)));

+    $1 = (char **) malloc((size+1) * sizeof(char *));

     pyVector = calloc(sizeof *pyVector, size);

     for (i = 0; i < size; i++) {

@@ -86,12 +89,7 @@

         {

           pyVector[i] = PyUnicode_AsUTF8String(o);

           if (pyVector[i] == NULL)

-            {

-              free(vector);

-              for (j = 0; j < i; j++)

-                Py_XDECREF(pyVector[j]);

-              return NULL;

-            }

+            SWIG_fail;

           $1[i] = PyBytes_AsString(pyVector[i]);

         }

       else if (PyString_Check(o))

@@ -101,8 +99,7 @@

                      "arg %d: list must contain only str or bytes, got %s "

                      "at position %d",

                      $argnum, o->ob_type->tp_name, i);

-	free($1);

-	return NULL;

+	SWIG_fail;

       }

     }

     $1[i] = NULL;

@@ -110,14 +107,17 @@

     PyErr_Format(PyExc_TypeError,

                  "arg %d: expected a list of str or bytes, got %s",

                  $argnum, $input->ob_type->tp_name);

-    return NULL;

+    SWIG_fail;

   }

 }

 %typemap(freearg) const char *[] {

-  size_t i;

-  free(vector$argnum);

-  for (i = 0; i < size$argnum; i++)

-    Py_XDECREF(pyVector$argnum[i]);

+  if (pyVector$argnum) {

+    size_t i;

+    for (i = 0; i < size$argnum; i++)

+      Py_XDECREF(pyVector$argnum[i]);

+    free(pyVector$argnum);

+  }

+  if ($1) free($1);

 }

 /* Release returned buffers as necessary.  */

@@ -135,7 +135,7 @@

   if (!PySequence_Check($input)) {

     PyErr_Format(PyExc_ValueError, "arg %d: Expected a list of gpgme_key_t",

 		 $argnum);

-    return NULL;

+    SWIG_fail;

   }

   if((numb = PySequence_Length($input)) != 0) {

     $1 = (gpgme_key_t*)malloc((numb+1)*sizeof(gpgme_key_t));

@@ -152,8 +152,7 @@

                      "arg %d: list must contain only gpgme_key_ts, got %s "

                      "at position %d",

                      $argnum, pypointer->ob_type->tp_name, i);

-        free($1);

-	return NULL;

+	SWIG_fail;

       }

       Py_DECREF(pypointer);

     }

@@ -179,7 +178,7 @@

     pypointer = _gpg_obj2gpgme_data_t($input, $argnum, &wrapper,

                                        &bytesio, &view);

     if (pypointer == NULL)

-      return NULL;

+      SWIG_fail;

     have_view = !! view.obj;

     /* input = $input, 1 = $1, 1_descriptor = $1_descriptor */

@@ -189,7 +188,7 @@

     if ((SWIG_ConvertPtr(pypointer,(void **) &$1, $1_descriptor,

          SWIG_POINTER_EXCEPTION | $disown )) == -1) {

       Py_DECREF(pypointer);

-      return NULL;

+      SWIG_fail;

     }

     Py_DECREF(pypointer);

   }

@@ -346,6 +345,11 @@

     PyErr_SetString(PyExc_TypeError, "Numeric argument expected");

 }

+%typemap(arginit) (void *buffer, size_t size), (char *buf, size_t buflen) {

+  $1 = NULL;

+  $2 = 0;

+}

+

 /* Those are for gpgme_data_read() and gpgme_strerror_r().  */

 %typemap(in) (void *buffer, size_t size), (char *buf, size_t buflen) {

   {

@@ -359,12 +363,12 @@

     else

       {

         PyErr_SetString(PyExc_TypeError, "Numeric argument expected");

-        return NULL;

+        SWIG_fail;

       }

     if (tmp$argnum < 0) {

       PyErr_SetString(PyExc_ValueError, "Positive integer expected");

-      return NULL;

+      SWIG_fail;

     }

     $2 = (size_t) tmp$argnum;

     $1 = ($1_ltype) malloc($2+1);

@@ -373,11 +377,11 @@

 %typemap(argout) (void *buffer, size_t size), (char *buf, size_t buflen) {

   Py_XDECREF($result);   /* Blow away any previous result */

   if (result < 0) {      /* Check for I/O error */

-    free($1);

+    if ($1) free($1);

     return PyErr_SetFromErrno(PyExc_RuntimeError);

   }

   $result = PyBytes_FromStringAndSize($1,result);

-  free($1);

+  if ($1) free($1);

 }

 /* For gpgme_data_write, but should be universal.  */

@@ -390,11 +394,11 @@

     {

       encodedInput = PyUnicode_AsUTF8String($input);

       if (encodedInput == NULL)

-        return NULL;

+        SWIG_fail;

       if (PyBytes_AsStringAndSize(encodedInput, (char **) &$1, &ssize) == -1)

         {

           Py_DECREF(encodedInput);

-          return NULL;

+          SWIG_fail;

         }

     }

   else if (PyBytes_Check($input))

@@ -403,7 +407,7 @@

     PyErr_Format(PyExc_TypeError,

                  "arg %d: expected str, bytes, or None, got %s",

 		 $argnum, $input->ob_type->tp_name);

-    return NULL;

+    SWIG_fail;

   }

   if (! $1)

@@ -432,8 +436,17 @@

     size++;

   }

   $result = PyList_New(size);

+  if ($result == NULL)

+    SWIG_fail;

   for (i=0,curr=$1; i<size; i++,curr=curr->next) {

     PyObject *o = SWIG_NewPointerObj(SWIG_as_voidptr(curr), $1_descriptor, %newpointer_flags);

+    if (o == NULL) {

+      int j;

+      for (j = 0; j < i; j++)

+        Py_XDECREF(PyList_GetItem($result, j));

+      Py_DECREF($result);

+      SWIG_fail;

+    }

     PyList_SetItem($result, i, o);

   }

 }

@@ -446,6 +459,8 @@

   PyObject *fragile;

   fragile = SWIG_NewPointerObj(SWIG_as_voidptr($1), $1_descriptor,

                                %newpointer_flags);

+  if (fragile == NULL)

+    SWIG_fail;

   $result = _gpg_wrap_result(fragile, name);

   Py_DECREF(fragile);

 }

@@ -469,22 +484,28 @@ wrapresult(gpgme_vfs_mount_result_t, "VFSMountResult")

   }

   $result = PyList_New(size);

   if ($result == NULL)

-    return NULL;	/* raise */

+    SWIG_fail;	/* raise */

   for (i=0,curr=$1; i<size; i++,curr=curr->next) {

     PyObject *fragile, *o;

     fragile = SWIG_NewPointerObj(SWIG_as_voidptr(curr), $1_descriptor,

                                  %newpointer_flags);

     if (fragile == NULL)

       {

+        int j;

+        for (j = 0; j < i; j++)

+          Py_XDECREF(PyList_GetItem($result, j));

         Py_DECREF($result);

-        return NULL;	/* raise */

+        SWIG_fail;	/* raise */

       }

     o = _gpg_wrap_result(fragile, "EngineInfo");

     Py_DECREF(fragile);

     if (o == NULL)

       {

+        int j;

+        for (j = 0; j < i; j++)

+          Py_XDECREF(PyList_GetItem($result, j));

         Py_DECREF($result);

-        return NULL;	/* raise */

+        SWIG_fail;	/* raise */

       }

     PyList_SetItem($result, i, o);

   }

diff --git a/src/engine-gpg.c b/src/engine-gpg.c

index dc2d9455..a1e40fe2 100644

--- a/src/engine-gpg.c

+++ b/src/engine-gpg.c

@@ -1122,6 +1122,7 @@ build_argv (engine_gpg_t gpg, const char *pgmname)

                    to avoid and given that we reach this here only

                    after a malloc failure for a small object, it is

                    probably better not to do anything.  */

+		free_argv (argv);

 		return gpg_error (GPG_ERR_GENERAL);

 	      }

 	    /* If the data_type is FD, we have to do a dup2 here.  */

@@ -1239,6 +1240,9 @@ read_status (engine_gpg_t gpg)

       buffer = realloc (buffer, bufsize);

       if (!buffer)

 	return gpg_error_from_syserror ();

+      /* Update buffer and bufsize here to prevent memory leaks.  */

+      gpg->status.buffer = buffer;

+      gpg->status.bufsize = bufsize;

     }

   nread = _gpgme_io_read (gpg->status.fd[0],

@@ -1351,8 +1355,6 @@ read_status (engine_gpg_t gpg)

     }

   /* Update the gpg object.  */

-  gpg->status.bufsize = bufsize;

-  gpg->status.buffer = buffer;

   gpg->status.readpos = readpos;

   return 0;

 }

@@ -1392,6 +1394,9 @@ read_colon_line (engine_gpg_t gpg)

       buffer = realloc (buffer, bufsize);

       if (!buffer)

 	return gpg_error_from_syserror ();

+      /* Prevent memory leaks.  */

+      gpg->colon.bufsize = bufsize;

+      gpg->colon.buffer  = buffer;

     }

   nread = _gpgme_io_read (gpg->colon.fd[0], buffer+readpos, bufsize-readpos);

@@ -1471,8 +1476,6 @@ read_colon_line (engine_gpg_t gpg)

     }

   /* Update the gpg object.  */

-  gpg->colon.bufsize = bufsize;

-  gpg->colon.buffer  = buffer;

   gpg->colon.readpos = readpos;

   return 0;

 }

diff --git a/src/engine-gpgsm.c b/src/engine-gpgsm.c

index ae5d8ef1..1f603f19 100644

--- a/src/engine-gpgsm.c

+++ b/src/engine-gpgsm.c

@@ -1533,8 +1533,10 @@ gpgsm_export (void *engine, const char *pattern, gpgme_export_mode_t mode,

   gpgsm->output_cb.data = keydata;

   err = gpgsm_set_fd (gpgsm, OUTPUT_FD, use_armor ? "--armor"

 		      : map_data_enc (gpgsm->output_cb.data));

-  if (err)

+  if (err) {

+    free (cmd);

     return err;

+  }

   gpgsm_clear_fd (gpgsm, INPUT_FD);

   gpgsm_clear_fd (gpgsm, MESSAGE_FD);

   gpgsm->inline_data = NULL;

@@ -1634,8 +1636,10 @@ gpgsm_export_ext (void *engine, const char *pattern[], gpgme_export_mode_t mode,

   gpgsm->output_cb.data = keydata;

   err = gpgsm_set_fd (gpgsm, OUTPUT_FD, use_armor ? "--armor"

 		      : map_data_enc (gpgsm->output_cb.data));

-  if (err)

+  if (err) {

+    free (line);

     return err;

+  }

   gpgsm_clear_fd (gpgsm, INPUT_FD);

   gpgsm_clear_fd (gpgsm, MESSAGE_FD);

   gpgsm->inline_data = NULL;

diff --git a/src/engine.c b/src/engine.c

index 05979c15..7e2e3800 100644

--- a/src/engine.c

+++ b/src/engine.c

@@ -460,7 +460,8 @@ _gpgme_set_engine_info (gpgme_engine_info_t info, gpgme_protocol_t proto,

       if (!new_version)

         {

           free (new_file_name);

-          free (new_home_dir);

+          if (new_home_dir)

+            free (new_home_dir);

           return gpg_error_from_syserror ();

         }

     }

diff --git a/src/gpgme-tool.c b/src/gpgme-tool.c

index 7a0bfcb3..f4ddd83b 100644

--- a/src/gpgme-tool.c

+++ b/src/gpgme-tool.c

@@ -1189,6 +1189,7 @@ gt_get_key (gpgme_tool_t gt, const char *pattern, gpgme_key_t *r_key)

                  similar hack to sort out such duplicates but it can't

                  do that while listing keys.  */

               gpgme_key_unref (key);

+              key = NULL;

               goto try_next_key;

             }

 	  if (!err)

diff --git a/src/keylist.c b/src/keylist.c

index cdb115fd..b7cbf3c3 100644

--- a/src/keylist.c

+++ b/src/keylist.c

@@ -1321,6 +1321,7 @@ gpgme_get_key (gpgme_ctx_t ctx, const char *fpr, gpgme_key_t *r_key,

                  similar hack to sort out such duplicates but it can't

                  do that while listing keys.  */

               gpgme_key_unref (key);

+              key = NULL;

               goto try_next_key;

             }

 	  if (!err)