[clang-tools-extra] 1c05651 - [clang] [C23] Fix crash with _BitInt running clang-tidy (#65889)

[via cfe-commits]

Author: vabridgers
Date: 2023-09-20T05:06:45-05:00
New Revision: 1c05651426297c773334943b9e8875bcc67b5db3

URL: https://github.com/llvm/llvm-project/commit/1c05651426297c773334943b9e8875bcc67b5db3
DIFF: https://github.com/llvm/llvm-project/commit/1c05651426297c773334943b9e8875bcc67b5db3.diff

LOG: [clang] [C23] Fix crash with _BitInt running clang-tidy (#65889)

This crash was exposed recently in our randomized testing. _BitInts were
not being handled properly during IntegerLiteral visitation. This patch
addresses the problem for now.

The BitIntType has no getKind() method, so the FoldingSetID is taken
from the APInt value representing the _BitInt(), similar to other
methods in StmtProfile.cpp.

Crash seen (summary form):

clang-tidy: <src-root>/llvm/include/llvm/Support/Casting.h:566:
decltype(auto) llvm::cast(const From&) [with To = clang::BuiltinType;
>From = clang::QualType]: Assertion `isa<To>(Val) && "cast<Ty>() argument
of incompatible type!"' failed

```
  #9 <address> decltype(auto) llvm::cast<clang::BuiltinType,
       clang::QualType>(clang::QualType const&)
       <src-root>/llvm/include/llvm/Support/Casting.h:566:3
 #10 <address> clang::BuiltinType const* clang::Type::castAs<clang::BuiltinType>() const
       <bin-root>/tools/clang/include/clang/AST/TypeNodes.inc:86:1
 #11 <address> (anonymous namespace)::StmtProfiler::VisitIntegerLiteral(
       clang::IntegerLiteral const*)
       <src-root>/clang/lib/AST/StmtProfile.cpp:1362:64
 #12 <address> clang::StmtVisitorBase<llvm::make_const_ptr,
       (anonymous namespace)::StmtProfiler, void>::Visit(clang::Stmt const*)
       <src-root>/clang/include/clang/AST/StmtNodes.inc:1225:1
```

Reviewed By: donat.nagy

Added: 
    clang-tools-extra/test/clang-tidy/checkers/bugprone/inc-dec-in-conditions-bitint-no-crash.c

Modified: 
    clang/include/clang/AST/Type.h
    clang/lib/AST/StmtProfile.cpp

Removed: 
    


################################################################################
diff  --git a/clang-tools-extra/test/clang-tidy/checkers/bugprone/inc-dec-in-conditions-bitint-no-crash.c b/clang-tools-extra/test/clang-tidy/checkers/bugprone/inc-dec-in-conditions-bitint-no-crash.c
new file mode 100644
index 000000000000000..cfb64c10fe46cea
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/checkers/bugprone/inc-dec-in-conditions-bitint-no-crash.c
@@ -0,0 +1,9 @@
+// RUN: %check_clang_tidy %s bugprone-inc-dec-in-conditions %t
+
+_BitInt(8) v_401_0() {
+  0 && ({
+    _BitInt(5) y = 0;
+    16777215wb ?: ++y;
+  });
+}
+// CHECK-MESSAGES: warning 

diff  --git a/clang/include/clang/AST/Type.h b/clang/include/clang/AST/Type.h
index 46dbadd8b878bf0..4799f89db82fa7f 100644
--- a/clang/include/clang/AST/Type.h
+++ b/clang/include/clang/AST/Type.h
@@ -6642,7 +6642,7 @@ class BitIntType final : public Type, public llvm::FoldingSetNode {
   bool isSugared() const { return false; }
   QualType desugar() const { return QualType(this, 0); }
 
-  void Profile(llvm::FoldingSetNodeID &ID) {
+  void Profile(llvm::FoldingSetNodeID &ID) const {
     Profile(ID, isUnsigned(), getNumBits());
   }
 

diff  --git a/clang/lib/AST/StmtProfile.cpp b/clang/lib/AST/StmtProfile.cpp
index 27f71edd6f99b32..2e4f15f83ac26ef 100644
--- a/clang/lib/AST/StmtProfile.cpp
+++ b/clang/lib/AST/StmtProfile.cpp
@@ -1333,7 +1333,13 @@ void StmtProfiler::VisitPredefinedExpr(const PredefinedExpr *S) {
 void StmtProfiler::VisitIntegerLiteral(const IntegerLiteral *S) {
   VisitExpr(S);
   S->getValue().Profile(ID);
-  ID.AddInteger(S->getType()->castAs<BuiltinType>()->getKind());
+
+  QualType T = S->getType();
+  ID.AddInteger(T->getTypeClass());
+  if (auto BitIntT = T->getAs<BitIntType>())
+    BitIntT->Profile(ID);
+  else
+    ID.AddInteger(T->castAs<BuiltinType>()->getKind());
 }
 
 void StmtProfiler::VisitFixedPointLiteral(const FixedPointLiteral *S) {