[clang] [lldb] [llvm] [APInt] Fix APInt constructions where value does not fit bitwidth (NFCI) (PR #80309)

[Nikita Popov via cfe-commits]

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@@ -3600,8 +3600,11 @@ ExprResult Sema::ActOnCharacterConstant(const Token &Tok, Scope *UDLScope) {
 
 ExprResult Sema::ActOnIntegerConstant(SourceLocation Loc, uint64_t Val) {
   unsigned IntSize = Context.getTargetInfo().getIntWidth();
-  return IntegerLiteral::Create(Context, llvm::APInt(IntSize, Val),
-                                Context.IntTy, Loc);
+  // TODO: Avoid implicit trunc?
+  return IntegerLiteral::Create(
+      Context,
+      llvm::APInt(IntSize, Val, /*isSigned=*/false, /*implicitTrunc=*/true),
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nikic wrote:

I've changed this to set isSigned=true and updated the signature to use int64_t instead of uint64_t to clarify that a signed value is expected.

https://github.com/llvm/llvm-project/pull/80309