Auto merge of #104673 - matthiaskrgr:rollup-85f65ov, r=matthiaskrgr

Rollup of 9 pull requests

Successful merges:

 - #104420 (Fix doc example for `wrapping_abs`)
 - #104499 (rustdoc JSON: Use `Function` everywhere and remove `Method`)
 - #104500 (`rustc_ast`: remove `ref` patterns)
 - #104511 (Mark functions created for `raw-dylib` on x86 with DllImport storage class)
 - #104595 (Add `PolyExistentialPredicate` type alias)
 - #104605 (deduplicate constant evaluation in cranelift backend)
 - #104628 (Revert "Update CI to use Android NDK r25b")
 - #104662 (Streamline deriving on packed structs.)
 - #104667 (Revert formatting changes of a test)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

1 files changed, 14 insertions, 1 deletions

diff --git a/compiler/rustc_codegen_llvm/src/callee.rs b/compiler/rustc_codegen_llvm/src/callee.rs
index 6f0d1b7ce84..70ff5c9617b 100644
--- a/compiler/rustc_codegen_llvm/src/callee.rs
+++ b/compiler/rustc_codegen_llvm/src/callee.rs
@@ -83,7 +83,20 @@ pub fn get_fn<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>, instance: Instance<'tcx>) ->
         let llfn = if tcx.sess.target.arch == "x86" &&
             let Some(dllimport) = common::get_dllimport(tcx, instance_def_id, sym)
         {
-            cx.declare_fn(&common::i686_decorated_name(&dllimport, common::is_mingw_gnu_toolchain(&tcx.sess.target), true), fn_abi)
+            // Fix for https://github.com/rust-lang/rust/issues/104453
+            // On x86 Windows, LLVM uses 'L' as the prefix for any private
+            // global symbols, so when we create an undecorated function symbol
+            // that begins with an 'L' LLVM misinterprets that as a private
+            // global symbol that it created and so fails the compilation at a
+            // later stage since such a symbol must have a definition.
+            //
+            // To avoid this, we set the Storage Class to "DllImport" so that
+            // LLVM will prefix the name with `__imp_`. Ideally, we'd like the
+            // existing logic below to set the Storage Class, but it has an
+            // exemption for MinGW for backwards compatability.
+            let llfn = cx.declare_fn(&common::i686_decorated_name(&dllimport, common::is_mingw_gnu_toolchain(&tcx.sess.target), true), fn_abi);
+            unsafe { llvm::LLVMSetDLLStorageClass(llfn, llvm::DLLStorageClass::DllImport); }
+            llfn
         } else {
             cx.declare_fn(sym, fn_abi)
         };