move PR1604 here.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57582 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/README.txt b/lib/Target/README.txt
index 173c0bc5f3934660dabf2f2385f9f399f7b28b94..9831efbdf64d247bb8a0cdb348d0f95ac784171a 100644 (file)
--- a/lib/Target/README.txt
+++ b/lib/Target/README.txt
@@ -954,3 +954,20 @@ should remove it, but it doesn't apply to memory objects.
 
 //===---------------------------------------------------------------------===//
 
+Better mod/ref analysis for scanf would allow us to eliminate the vtable and a
+bunch of other stuff from this example (see PR1604): 
+
+#include <cstdio>
+struct test {
+    int val;
+    virtual ~test() {}
+};
+
+int main() {
+    test t;
+    std::scanf("%d", &t.val);
+    std::printf("%d\n", t.val);
+}
+
+//===---------------------------------------------------------------------===//
+