  #include <cmath>
  #include <iostream>
  #include <stdexcept>
+diff --git a/gr-fec/python/fec/bindings/fec_mtrx_python.cc b/gr-fec/python/fec/bindings/fec_mtrx_python.cc
+index b7a7a6b7c..eb2d04093 100644
+--- a/gr-fec/python/fec/bindings/fec_mtrx_python.cc
++++ b/gr-fec/python/fec/bindings/fec_mtrx_python.cc
+@@ -14,7 +14,7 @@
+ /* BINDTOOL_GEN_AUTOMATIC(0)                                                       */
+ /* BINDTOOL_USE_PYGCCXML(0)                                                        */
+ /* BINDTOOL_HEADER_FILE(fec_mtrx.h)                                        */
+-/* BINDTOOL_HEADER_FILE_HASH(80c2f34bc9bdb9ac03abdf0c26b3d024)                     */
++/* BINDTOOL_HEADER_FILE_HASH(27f3285cd440f36bd0cb37fb3371c395)                     */
+ /***********************************************************************************/
+ 
+ #include <pybind11/complex.h>
+diff --git a/gr-fec/python/fec/bindings/ldpc_G_matrix_python.cc b/gr-fec/python/fec/bindings/ldpc_G_matrix_python.cc
+index edda371cd..9fd266dce 100644
+--- a/gr-fec/python/fec/bindings/ldpc_G_matrix_python.cc
++++ b/gr-fec/python/fec/bindings/ldpc_G_matrix_python.cc
+@@ -14,7 +14,7 @@
+ /* BINDTOOL_GEN_AUTOMATIC(0)                                                       */
+ /* BINDTOOL_USE_PYGCCXML(0)                                                        */
+ /* BINDTOOL_HEADER_FILE(ldpc_G_matrix.h)                                        */
+-/* BINDTOOL_HEADER_FILE_HASH(e7cba655800bc51dc4ee066fbd16f621)                     */
++/* BINDTOOL_HEADER_FILE_HASH(bf2a99993f1ad2c3e1ebbe9d6d29a507)                     */
+ /***********************************************************************************/
+ 
+ #include <pybind11/complex.h>
+diff --git a/gr-fec/python/fec/bindings/ldpc_H_matrix_python.cc b/gr-fec/python/fec/bindings/ldpc_H_matrix_python.cc
+index 7c57b980c..7df602be3 100644
+--- a/gr-fec/python/fec/bindings/ldpc_H_matrix_python.cc
++++ b/gr-fec/python/fec/bindings/ldpc_H_matrix_python.cc
+@@ -14,7 +14,7 @@
+ /* BINDTOOL_GEN_AUTOMATIC(0)                                                       */
+ /* BINDTOOL_USE_PYGCCXML(0)                                                        */
+ /* BINDTOOL_HEADER_FILE(ldpc_H_matrix.h)                                        */
+-/* BINDTOOL_HEADER_FILE_HASH(68956287d34e6a1208c0d84fda0d8af4)                     */
++/* BINDTOOL_HEADER_FILE_HASH(aeff2a97ade352d218316adfe97a4b6d)                     */
+ /***********************************************************************************/
+ 
+ #include <pybind11/complex.h>
 -- 
 2.20.1
 

This fixes compilation with MSVC on conda-forge, although why this
wasn't needed earlier is a mystery.
---
 gnuradio-runtime/lib/io_signature.cc        | 1 +
 gr-fec/include/gnuradio/fec/fec_mtrx.h      | 1 +
 gr-fec/include/gnuradio/fec/ldpc_G_matrix.h | 1 +
 gr-fec/lib/polar_common.cc                  | 1 +
 4 files changed, 4 insertions(+)

diff --git a/gnuradio-runtime/lib/io_signature.cc b/gnuradio-runtime/lib/io_signature.cc
index e5fd2bdd7..b330e56c3 100644

 
 namespace gr {
 namespace fec {
diff --git a/gr-fec/include/gnuradio/fec/ldpc_H_matrix.h b/gr-fec/include/gnuradio/fec/ldpc_H_matrix.h
index 9a3628a52..b4c793f82 100644
--- a/gr-fec/include/gnuradio/fec/ldpc_H_matrix.h
+++ b/gr-fec/include/gnuradio/fec/ldpc_H_matrix.h
@@ -12,6 +12,7 @@
 #include <gnuradio/fec/api.h>
 #include <gnuradio/fec/fec_mtrx.h>
 #include <memory>
+#include <string>
 
 namespace gr {
 namespace fec {
diff --git a/gr-fec/lib/polar_common.cc b/gr-fec/lib/polar_common.cc
index 6df894766..1b2a13137 100644
--- a/gr-fec/lib/polar_common.cc
