[clang] [analyzer] Refactor recognition of the errno getter functions (PR #91531)

[Balázs Kéri via cfe-commits]

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@@ -54,16 +59,10 @@ class ErrnoModeling
   void checkLiveSymbols(ProgramStateRef State, SymbolReaper &SR) const;
   bool evalCall(const CallEvent &Call, CheckerContext &C) const;
 
-  // The declaration of an "errno" variable or "errno location" function.
-  mutable const Decl *ErrnoDecl = nullptr;
-
 private:
-  // FIXME: Names from `ErrnoLocationFuncNames` are used to build this set.
-  CallDescriptionSet ErrnoLocationCalls{{{"__errno_location"}, 0, 0},
-                                        {{"___errno"}, 0, 0},
-                                        {{"__errno"}, 0, 0},
-                                        {{"_errno"}, 0, 0},
-                                        {{"__error"}, 0, 0}};
+  // The declaration of an "errno" variable on systems where errno is
+  // represented by a variable (and not a function that queries its location).
+  mutable const Decl *ErrnoDecl = nullptr;
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balazske wrote:

This can be changed to `VarDecl`.

https://github.com/llvm/llvm-project/pull/91531