Add some notes for SCA.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@58597 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/NOTES.TXT b/lib/Analysis/NOTES.TXT
index 97b7bf7..54ce078 100644
--- a/lib/Analysis/NOTES.TXT
+++ b/lib/Analysis/NOTES.TXT
@@ -22,3 +22,34 @@
//===----------------------------------------------------------------------===//
Remove PersistentSValPairs and PersistentSVals?
+
+//===----------------------------------------------------------------------===//
+
+If the pointer is symbolic, we should expand it to a full region with symbolic
+values. This can eliminate the following false warning.
+
+struct file {
+ int lineno;
+};
+
+struct file *fileinfo;
+
+void f10() {
+ int i;
+ int *p = 0;
+
+ if (fileinfo->lineno)
+ p = &i;
+
+ if (fileinfo->lineno)
+ *p = 3; // false warning
+}
+
+Now we return a symbolic region for fileinfo->lineno in RegionStore. Loading
+from it returns an UnknownVal. Therefore the path condition is not recorded.
+
+Where should we call this ExpandSymbolicPointer method? Perhaps in
+GRExprEngine::VisitMemberExpr().
+
+Problem: The base expr of MemberExpr can be in various form. How do we get the
+pointer varregion(or other kind of region) to be changed?