Index: generic/tclCmdIL.c
==================================================================
--- generic/tclCmdIL.c
+++ generic/tclCmdIL.c
@@ -3100,11 +3100,11 @@
 
     if (last >= listLen) {
 	last = listLen - 1;
     }
     if (first <= last) {
-	numToDelete = last - first + 1;
+	numToDelete = (unsigned)last - (unsigned)first + 1; /* See [3d3124d01d] */
     } else {
 	numToDelete = 0;
     }
 
     /*
@@ -5080,11 +5080,11 @@
 
     if (last >= listLen) {
 	last = listLen - 1;
     }
     if (first <= last) {
-	numToDelete = last - first + 1;
+	numToDelete = (unsigned)last - (unsigned)first + 1; /* See [3d3124d01d] */
     } else {
 	numToDelete = 0;
     }
 
     if (Tcl_IsShared(listPtr)) {

Index: generic/tclExecute.c
==================================================================
--- generic/tclExecute.c
+++ generic/tclExecute.c
@@ -5291,11 +5291,11 @@
 	    }
 	    if (toIdx > length) {
 		toIdx = length;
 	    }
 	    if (toIdx >= fromIdx) {
-		numToDelete = toIdx - fromIdx + 1;
+		numToDelete = (unsigned)toIdx - (unsigned)fromIdx + 1; /* See [3d3124d01d] */
 	    }
 	}
 
 	CACHE_STACK_INFO();