diff --git a/bindings/python/sigrok/core/classes.i b/bindings/python/sigrok/core/classes.i
index f8620abe..374996d5 100644
--- a/bindings/python/sigrok/core/classes.i
+++ b/bindings/python/sigrok/core/classes.i
@@ -26,6 +26,14 @@ PyObject *GLib;
 PyTypeObject *IOChannel;
 PyTypeObject *PollFD;
 
+#include "../../../../config.h"
+
+#if PYGOBJECT_FLAGS_SIGNED
+typedef gint pyg_flags_type;
+#else
+typedef guint pyg_flags_type;
+#endif
+
 %}
 
 %init %{
@@ -64,7 +72,7 @@ PyTypeObject *PollFD;
 
 /* Map from Glib::IOCondition to GLib.IOCondition. */
 %typecheck(SWIG_TYPECHECK_POINTER) Glib::IOCondition {
-    gint flags;
+    pyg_flags_type flags;
     $1 = pygobject_check($input, &PyGFlags_Type) &&
          (pyg_flags_get_value(G_TYPE_IO_CONDITION, $input, &flags) != -1);
 }
@@ -72,7 +80,7 @@ PyTypeObject *PollFD;
 %typemap(in) Glib::IOCondition {
     if (!pygobject_check($input, &PyGFlags_Type))
         SWIG_exception(SWIG_TypeError, "Expected GLib.IOCondition value");
-    gint flags;
+    pyg_flags_type flags;
     if (pyg_flags_get_value(G_TYPE_IO_CONDITION, $input, &flags) == -1)
         SWIG_exception(SWIG_TypeError, "Not a valid Glib.IOCondition value");
     $1 = (Glib::IOCondition) flags;
@@ -97,7 +105,7 @@ PyTypeObject *PollFD;
         SWIG_exception(SWIG_TypeError, "Expected GLib.PollFD");
     PyObject *fd_obj = PyObject_GetAttrString($input, "fd");
     PyObject *events_obj = PyObject_GetAttrString($input, "events");
-    gint flags;
+    pyg_flags_type flags;
     pyg_flags_get_value(G_TYPE_IO_CONDITION, events_obj, &flags);
     int fd = PyInt_AsLong(fd_obj);
     Glib::IOCondition events = (Glib::IOCondition) flags;
diff --git a/configure.ac b/configure.ac
index 690dc2c6..971f9a7e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -367,7 +367,12 @@ PKG_CHECK_MODULES([glibmm], [glibmm-2.4 >= 2.32.0],
 # PyGObject is needed for the Python bindings.
 PKG_CHECK_MODULES([pygobject], [pygobject-3.0],
         [CXXFLAGS="$CXXFLAGS $pygobject_CFLAGS";
-        CXXLIBS="$CXXLIBS $pygobject_LIBS"], [BINDINGS_PYTHON="no"])
+        CXXLIBS="$CXXLIBS $pygobject_LIBS";
+	PKG_CHECK_MODULES([pygobject_3_7_91], [pygobject-3.0 >= 3.7.91],
+		[pyg_flags_signed=0], [pyg_flags_signed=1]);
+	AC_DEFINE_UNQUOTED(PYGOBJECT_FLAGS_SIGNED, [$pyg_flags_signed],
+		[Whether last argument to pyg_flags_get_value() is signed])],
+	[BINDINGS_PYTHON="no"])
 
 # The Check unit testing framework is optional. Disable if not found.
 PKG_CHECK_MODULES([check], [check >= 0.9.4],