[clang][bytecode] Typecheck called function pointers more thorougly (#159757)

Fix two older FIXME items from the `functions.cpp` test.

1 files changed, 10 insertions, 3 deletions

diff --git a/clang/lib/AST/ByteCode/Interp.cpp b/clang/lib/AST/ByteCode/Interp.cpp
index d5e75a0..0f322f6 100644
--- a/clang/lib/AST/ByteCode/Interp.cpp
+++ b/clang/lib/AST/ByteCode/Interp.cpp
@@ -1750,9 +1750,8 @@ bool CallPtr(InterpState &S, CodePtr OpPC, uint32_t ArgSize,
   const Pointer &Ptr = S.Stk.pop<Pointer>();
 
   if (Ptr.isZero()) {
-    const auto *E = cast<CallExpr>(S.Current->getExpr(OpPC));
-    S.FFDiag(E, diag::note_constexpr_null_callee)
-        << const_cast<Expr *>(E->getCallee()) << E->getSourceRange();
+    S.FFDiag(S.Current->getSource(OpPC), diag::note_constexpr_null_callee)
+        << const_cast<Expr *>(CE->getCallee()) << CE->getSourceRange();
     return false;
   }
 
@@ -1778,6 +1777,14 @@ bool CallPtr(InterpState &S, CodePtr OpPC, uint32_t ArgSize,
       return false;
   }
 
+  // Can happen when casting function pointers around.
+  QualType CalleeType = CE->getCallee()->getType();
+  if (CalleeType->isPointerType() &&
+      !S.getASTContext().hasSameFunctionTypeIgnoringExceptionSpec(
+          F->getDecl()->getType(), CalleeType->getPointeeType())) {
+    return false;
+  }
+
   assert(ArgSize >= F->getWrittenArgSize());
   uint32_t VarArgSize = ArgSize - F->getWrittenArgSize();