Move variable declaration to the top of the block,
to let _json.c compile with Microsoft compilers.
diff --git a/Modules/_json.c b/Modules/_json.c
index 39d39cb..890d27e 100644
--- a/Modules/_json.c
+++ b/Modules/_json.c
@@ -256,10 +256,11 @@
         }
         /* Pick up this chunk if it's not zero length */
         if (next != end) {
+            PyObject *strchunk;
             if (PyBuffer_FillInfo(&info, &buf[end], next - end, 1, 0) < 0) {
                 goto bail;
             }
-            PyObject *strchunk = PyMemoryView_FromMemory(&info);
+            strchunk = PyMemoryView_FromMemory(&info);
             if (strchunk == NULL) {
                 goto bail;
             }