[clang] [NFC][analyzer] Eliminate SwitchNodeBuilder (PR #188096)

[Donát Nagy via cfe-commits]

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@@ -3154,7 +3156,18 @@ void ExprEngine::processSwitch(const SwitchStmt *Switch, ExplodedNode *Pred,
         continue;
     }
 
-    Builder.generateDefaultCaseNode(State, Node);
+    // Get the block for the default case.
+    const CFGBlock *Src = getCurrBlock();
+    assert(Src->succ_rbegin() != Src->succ_rend());
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NagyDonat wrote:

I ended up completely omitting this assertion in a later change, but I can re-add it if you prefer.

https://github.com/llvm/llvm-project/pull/188096