--- /dev/null
+/* Verify that -Wformat-overflow uses context-sensitive ranges even
+ at -O0 to avoid both false positives and negatives.
+ { dg-do compile }
+ { dg-options "-O0 -Wall" } */
+
+extern int sprintf (char*, const char*, ...);
+
+extern char a[4];
+
+void test_context_range (int c)
+{
+ int i = 998;
+
+ /* Prior to the switch to Ranger in GCC 12 -Wformat-overflow triggers
+ for both calls because EVRP doesn't expose the accurate range of
+ the argument. */
+ if (c)
+ sprintf (a, "%i", i + 2); // { dg-warning "writing a terminating nul past the end of the destination" }
+ else
+ sprintf (a, "%i", i + 1); // { dg-bogus "-Wformat-overflow" }
+}