diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata/type_map.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata/type_map.rs
index 18a783a348a4..af72d4ea3de0 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata/type_map.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata/type_map.rs
@@ -1,5 +1,6 @@
 use std::cell::RefCell;
 
+use libc::c_uint;
 use rustc_abi::{Align, Size, VariantIdx};
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::FxHashMap;
@@ -191,6 +192,7 @@ pub(super) fn stub<'ll, 'tcx>(
     containing_scope: Option<&'ll DIScope>,
     flags: DIFlags,
 ) -> StubInfo<'ll, 'tcx> {
+    let no_elements: &[Option<&llvm::Metadata>] = &[];
     let empty_array = create_DIArray(DIB(cx), &[]);
     let unique_type_id_str = unique_type_id.generate_unique_id_string(cx.tcx);
 
@@ -227,19 +229,20 @@ pub(super) fn stub<'ll, 'tcx>(
             }
         }
         Stub::Union => unsafe {
-            llvm::LLVMRustDIBuilderCreateUnionType(
+            llvm::LLVMDIBuilderCreateUnionType(
                 DIB(cx),
                 containing_scope,
-                name.as_c_char_ptr(),
+                name.as_ptr(),
                 name.len(),
                 file_metadata,
                 line_number,
                 size.bits(),
                 align.bits() as u32,
                 flags,
-                Some(empty_array),
-                0,
-                unique_type_id_str.as_c_char_ptr(),
+                no_elements.as_ptr(),
+                no_elements.len() as c_uint,
+                0u32, // (Objective-C runtime version; default is 0)
+                unique_type_id_str.as_ptr(),
                 unique_type_id_str.len(),
             )
         },
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index af0ec6a33b0d..58aebe4c391e 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -1878,6 +1878,23 @@ unsafe extern "C" {
         NumParameterTypes: c_uint,
         Flags: DIFlags, // (default is `DIFlags::DIFlagZero`)
     ) -> &'ll Metadata;
+
+    pub(crate) fn LLVMDIBuilderCreateUnionType<'ll>(
+        Builder: &DIBuilder<'ll>,
+        Scope: Option<&'ll Metadata>,
+        Name: *const c_uchar, // See "PTR_LEN_STR".
+        NameLen: size_t,
+        File: &'ll Metadata,
+        LineNumber: c_uint,
+        SizeInBits: u64,
+        AlignInBits: u32,
+        Flags: DIFlags,
+        Elements: *const Option<&'ll Metadata>,
+        NumElements: c_uint,
+        RunTimeLang: c_uint, // (optional Objective-C runtime version; default is 0)
+        UniqueId: *const c_uchar, // See "PTR_LEN_STR".
+        UniqueIdLen: size_t,
+    ) -> &'ll Metadata;
 }
 
 #[link(name = "llvm-wrapper", kind = "static")]
@@ -2391,22 +2408,6 @@ unsafe extern "C" {
         IsScoped: bool,
     ) -> &'a DIType;
 
-    pub(crate) fn LLVMRustDIBuilderCreateUnionType<'a>(
-        Builder: &DIBuilder<'a>,
-        Scope: Option<&'a DIScope>,
-        Name: *const c_char,
-        NameLen: size_t,
-        File: &'a DIFile,
-        LineNumber: c_uint,
-        SizeInBits: u64,
-        AlignInBits: u32,
-        Flags: DIFlags,
-        Elements: Option<&'a DIArray>,
-        RunTimeLang: c_uint,
-        UniqueId: *const c_char,
-        UniqueIdLen: size_t,
-    ) -> &'a DIType;
-
     pub(crate) fn LLVMRustDIBuilderCreateVariantPart<'a>(
         Builder: &DIBuilder<'a>,
         Scope: &'a DIScope,
diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
index a1c3cce99202..2cbfcf79c83d 100644
--- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
@@ -1268,19 +1268,6 @@ extern "C" LLVMMetadataRef LLVMRustDIBuilderCreateEnumerationType(
       /* RunTimeLang */ 0, "", IsScoped));
 }
 
-extern "C" LLVMMetadataRef LLVMRustDIBuilderCreateUnionType(
-    LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
-    size_t NameLen, LLVMMetadataRef File, unsigned LineNumber,
-    uint64_t SizeInBits, uint32_t AlignInBits, LLVMDIFlags Flags,
-    LLVMMetadataRef Elements, unsigned RunTimeLang, const char *UniqueId,
-    size_t UniqueIdLen) {
-  return wrap(unwrap(Builder)->createUnionType(
-      unwrapDI<DIDescriptor>(Scope), StringRef(Name, NameLen),
-      unwrapDI<DIFile>(File), LineNumber, SizeInBits, AlignInBits,
-      fromRust(Flags), DINodeArray(unwrapDI<MDTuple>(Elements)), RunTimeLang,
-      StringRef(UniqueId, UniqueIdLen)));
-}
-
 extern "C" LLVMMetadataRef LLVMRustDIBuilderCreateTemplateTypeParameter(
     LLVMDIBuilderRef Builder, LLVMMetadataRef Scope, const char *Name,
     size_t NameLen, LLVMMetadataRef Ty) {