Issue #19418 Fix some warnings on Win64
diff --git a/Modules/audioop.c b/Modules/audioop.c
index 5e1de1b..342f262 100644
--- a/Modules/audioop.c
+++ b/Modules/audioop.c
@@ -15,7 +15,8 @@
 #endif
 
 static const int maxvals[] = {0, 0x7F, 0x7FFF, 0x7FFFFF, 0x7FFFFFFF};
-static const int minvals[] = {0, -0x80, -0x8000, -0x800000, -0x80000000};
+/* -1 trick is needed on Windows to support -0x80000000 without a warning */
+static const int minvals[] = {0, -0x80, -0x8000, -0x800000, -0x7FFFFFFF-1};
 static const unsigned int masks[] = {0, 0xFF, 0xFFFF, 0xFFFFFF, 0xFFFFFFFF};
 
 static int
@@ -434,7 +435,9 @@
     signed char *cp;
     Py_ssize_t len, i;
     int size;
-    int min = 0x7fffffff, max = -0x80000000;
+    /* -1 trick below is needed on Windows to support -0x80000000 without
+    a warning */
+    int min = 0x7fffffff, max = -0x7FFFFFFF-1;
 
     if (!PyArg_ParseTuple(args, "s#i:minmax", &cp, &len, &size))
         return NULL;