[clang] [clang][analyzer] Stable order for SymbolRef-keyed containers (PR #121551)

[Balazs Benics via cfe-commits]

================
@@ -687,4 +711,35 @@ class SymbolVisitor {
 
 } // namespace clang
 
+// Override the default definition that would use pointer values of SymbolRefs
+// to order them, which is unstable due to ASLR.
+// Use the SymbolID instead which reflect the order in which the symbols were
+// allocated. This is usually stable across runs leading to the stability of
+// ConstraintMap and other containers using SymbolRef as keys.
+template <>
+struct ::llvm::ImutContainerInfo<clang::ento::SymbolRef>
+    : public ImutProfileInfo<clang::ento::SymbolRef> {
+  using value_type =
+      typename ImutProfileInfo<clang::ento::SymbolRef>::value_type;
+  using value_type_ref =
+      typename ImutProfileInfo<clang::ento::SymbolRef>::value_type_ref;
+  using key_type = value_type;
+  using key_type_ref = value_type_ref;
+  using data_type = bool;
+  using data_type_ref = bool;
----------------
steakhal wrote:

I rarely ever de fined my own ImutInfo but I wonder where the data type comes from. I could only see a single type parameter for this template specialization, and I was expecting a partial specialization leaving the Data type unbound. Could you explain this to me?
Maybe we could leave a comment at the `isDataEqual` where the same question would come up.

https://github.com/llvm/llvm-project/pull/121551