From 8975eb327427ea1963571c5c5bd1eb6778594f28 Mon Sep 17 00:00:00 2001
From: Nikita Popov <npopov@redhat.com>
Date: Thu, 11 Dec 2025 15:52:40 +0100
Subject: [PATCH] [FuzzerMutate] Allow implicit truncation

If the fixed value 42 does not fit the integer type, truncate it.
---
 llvm/lib/FuzzMutate/OpDescriptor.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/FuzzMutate/OpDescriptor.cpp b/llvm/lib/FuzzMutate/OpDescriptor.cpp
index 6ec70d917918..c7c5d77b7b9f 100644
--- a/llvm/lib/FuzzMutate/OpDescriptor.cpp
+++ b/llvm/lib/FuzzMutate/OpDescriptor.cpp
@@ -22,7 +22,8 @@ void fuzzerop::makeConstantsWithType(Type *T, std::vector<Constant *> &Cs) {
     uint64_t W = IntTy->getBitWidth();
     Cs.push_back(ConstantInt::get(IntTy, 0));
     Cs.push_back(ConstantInt::get(IntTy, 1));
-    Cs.push_back(ConstantInt::get(IntTy, 42));
+    Cs.push_back(ConstantInt::get(IntTy, 42, /*IsSigned=*/false,
+                                  /*ImplicitTrunc=*/true));
     Cs.push_back(ConstantInt::get(IntTy, APInt::getMaxValue(W)));
     Cs.push_back(ConstantInt::get(IntTy, APInt::getMinValue(W)));
     Cs.push_back(ConstantInt::get(IntTy, APInt::getSignedMaxValue(W)));