[clang] [clang][analyzer] Forward CTU-import failure conditions (PR #189064)

[Donát Nagy via cfe-commits]

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@@ -346,6 +347,8 @@ class CrossTranslationUnitContext {
   };
 
   ASTUnitStorage ASTStorage;
+
+  bool HasEmittedLoadThresholdRemark = false;
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NagyDonat wrote:

> I don't see a way interacting with the ASTImporter (thus mutating our **own** AST) without having irrecoverable side-effects. This is by definition, can't be avoided.

I mostly agree, but I have a (wild, unrefined) idea that in the distant future perhaps we could replace the current "we import what we need" lazy AST import with an eager process where the analyzer imports the definitions that are frequently called, not to large and heuristically "interesting" (based on some rough preliminary whole program analysis).

https://github.com/llvm/llvm-project/pull/189064