[clang] [clang] [Static analyzer]: add initial support for builtin overflow (PR #102602)

[Pavel Skripkin via cfe-commits]

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@@ -50,6 +101,44 @@ class BuiltinFunctionChecker : public Checker<eval::Call> {
 
 } // namespace
 
+void BuiltinFunctionChecker::HandleOverflowBuiltin(const CallEvent &Call,
+                                                   CheckerContext &C,
+                                                   BinaryOperator::Opcode Op,
+                                                   QualType ResultType) const {
+  // All __builtin_*_overflow functions take 3 argumets.
+  assert(Call.getNumArgs() == 3);
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pskrgag wrote:

Hm, I thought that CSA won't run on code with compile errors. Or there is a mode which will try to run even on invalid AST?

I've tried to catch this assert locally by calling `__builtin_*_overflow`  with 2 arguments, but clang just rejects it.

https://github.com/llvm/llvm-project/pull/102602