[PATCH] D31130: B32239 clang-tidy should not warn about array to pointer decay on system macros

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added inline comments.


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Comment at: clang-tidy/cppcoreguidelines/ProBoundsArrayToPointerDecayCheck.cpp:50
 
+AST_MATCHER(Stmt, isArrayToPointerDecay) {
+  const auto *MatchedCast = cast<ImplicitCastExpr>(&Node);
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Why not match on `ImplicitCastExpr` rather than `Stmt`? Then you can remove the explicit cast below.


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Comment at: clang-tidy/cppcoreguidelines/ProBoundsArrayToPointerDecayCheck.cpp:55
+
+AST_MATCHER(Stmt, sysSymbolDecayInSysHeader) {
+  const auto *E = cast<ImplicitCastExpr>(&Node);
----------------
Likewise here.


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Comment at: clang-tidy/cppcoreguidelines/ProBoundsArrayToPointerDecayCheck.cpp:59-60
+  if (SM.isInSystemMacro(E->getLocStart())) {
+    const auto *PredefSymbol = dyn_cast<PredefinedExpr>(E->getSubExpr());
+    if (PredefSymbol)
+      return true;
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I think this is better-expressed with an isa check: `if (isa<PredefinedExpr>(E->getSubExpr())) return true;`


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Comment at: clang-tidy/cppcoreguidelines/ProBoundsArrayToPointerDecayCheck.cpp:63-64
+
+    const auto *SymbolDeclRef = dyn_cast<DeclRefExpr>(E->getSubExpr());
+    if (SymbolDeclRef) {
+      const ValueDecl *SymbolDecl = SymbolDeclRef->getDecl();
----------------
You can combine these into `if (const auto *SDR = dyn_cast<>())`


https://reviews.llvm.org/D31130