[clang] [clang][dataflow] Fully support Environment construction for Stmt analysis. (PR #91616)

[Yitzhak Mandelbaum via cfe-commits]

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@@ -476,7 +476,7 @@ runTypeErasedDataflowAnalysis(
   PrettyStackTraceAnalysis CrashInfo(ACFG, "runTypeErasedDataflowAnalysis");
 
   std::optional<Environment> MaybeStartingEnv;
-  if (InitEnv.callStackSize() == 1) {
+  if (InitEnv.callStackSize() == 0) {
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ymand wrote:

aside: this line now feels more "right" than the original version.

https://github.com/llvm/llvm-project/pull/91616