Auto merge of #93670 - erikdesjardins:noundef, r=nikic

Apply noundef attribute to &T, &mut T, Box<T>, bool

This doesn't handle `char` because it's a bit awkward to distinguish it from `u32` at this point in codegen.

Note that this _does not_ change whether or not it is UB for `&`, `&mut`, or `Box` to point to undef. It only applies to the pointer itself, not the pointed-to memory.

Fixes (partially) #74378.

r? `@nikic` cc `@RalfJung`

1 files changed, 2 insertions, 0 deletions

diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
index d871290744f..fb9c5e6a527 100644
--- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
@@ -224,6 +224,8 @@ static Attribute::AttrKind fromRust(LLVMRustAttribute Kind) {
     return Attribute::StackProtectStrong;
   case StackProtect:
     return Attribute::StackProtect;
+  case NoUndef:
+    return Attribute::NoUndef;
   }
   report_fatal_error("bad AttributeKind");
 }