Auto merge of #86873 - nikic:opaque-ptrs, r=nagisa

Improve opaque pointers support

Opaque pointers are coming, and rustc is not ready.

This adds partial support by passing an explicit load type to LLVM. Two issues I've encountered:
 * The necessary type was not available at the point where non-temporal copies were generated. I've pushed the code for that upwards out of the memcpy implementation and moved the position of a cast to make do with the types we have available. (I'm not sure that cast is needed at all, but have retained it in the interest of conservativeness.)
 * The `PlaceRef::project_deref()` function used during debuginfo generation seems to be buggy in some way -- though I haven't figured out specifically what it does wrong. Replacing it with `load_operand().deref()` did the trick, but I don't really know what I'm doing here.

1 files changed, 1 insertions, 1 deletions

diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/gdb.rs b/compiler/rustc_codegen_llvm/src/debuginfo/gdb.rs
index 38f50a6d621..de3f719b816 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/gdb.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/gdb.rs
@@ -20,7 +20,7 @@ pub fn insert_reference_to_gdb_debug_scripts_section_global(bx: &mut Builder<'_,
         // LLVM to keep around the reference to the global.
         let indices = [bx.const_i32(0), bx.const_i32(0)];
         let element = bx.inbounds_gep(gdb_debug_scripts_section, &indices);
-        let volative_load_instruction = bx.volatile_load(element);
+        let volative_load_instruction = bx.volatile_load(bx.type_i8(), element);
         unsafe {
             llvm::LLVMSetAlignment(volative_load_instruction, 1);
         }