From ecbe2e8c3f8f4be87d5d30ad5d1fcc1986fa5c47 Mon Sep 17 00:00:00 2001
From: Andrew Rogers <andrurogerz@gmail.com>
Date: Wed, 4 Jun 2025 10:28:58 -0700
Subject: [llvm] annotate interfaces in llvm/ObjCopy and llvm/Object for DLL
 export (#142668)
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## Purpose

This patch is one in a series of code-mods that annotate LLVM’s public
interface for export. This patch annotates the `llvm/ObjCopy` and
`llvm/Object` libraries. These annotations currently have no meaningful
impact on the LLVM build; however, they are a prerequisite to support an
LLVM Windows DLL (shared library) build.

## Background

This effort is tracked in #109483. Additional context is provided in
[this
discourse](https://discourse.llvm.org/t/psa-annotating-llvm-public-interface/85307),
and documentation for `LLVM_ABI` and related annotations is found in the
LLVM repo
[here](https://github.com/llvm/llvm-project/blob/main/llvm/docs/InterfaceExportAnnotations.rst).

The bulk of these changes were generated automatically using the
[Interface Definition Scanner (IDS)](https://github.com/compnerd/ids)
tool, followed formatting with `git clang-format`.

The following manual adjustments were also applied after running IDS on
Linux:
- Add `#include "llvm/Support/Compiler.h"` to files where it was not
auto-added by IDS due to no pre-existing block of include statements.
- Manually annotate template class `CommonArchiveMemberHeader` with
`LLVM_ABI` since IDS ignores templates and this is the simplest solution
for DLL-exporting its child classes because it has methods defined
out-of-line. Seems to be an uncommon situation.
- Explicitly make `Archive` class non-copyable due to the class-level
`LLVM_ABI` annotation.
- Add default constructor to `ELFFile` so it can be instantiated for
DLL-export as a base class.
- Add `LLVM_TEMPLATE_ABI` and `LLVM_EXPORT_TEMPLATE` to exported
instantiated templates.

## Validation

Local builds and tests to validate cross-platform compatibility. This
included llvm, clang, and lldb on the following configurations:

- Windows with MSVC
- Windows with Clang
- Linux with GCC
- Linux with Clang
- Darwin with Clang
---
 llvm/lib/Object/XCOFFObjectFile.cpp | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

(limited to 'llvm/lib')

diff --git a/llvm/lib/Object/XCOFFObjectFile.cpp b/llvm/lib/Object/XCOFFObjectFile.cpp
index 5a24643..c5a2ec2 100644
--- a/llvm/lib/Object/XCOFFObjectFile.cpp
+++ b/llvm/lib/Object/XCOFFObjectFile.cpp
@@ -93,8 +93,8 @@ uint8_t XCOFFRelocation<AddressType>::getRelocatedLength() const {
   return (Info & XR_BIASED_LENGTH_MASK) + 1;
 }
 
-template struct ExceptionSectionEntry<support::ubig32_t>;
-template struct ExceptionSectionEntry<support::ubig64_t>;
+template struct LLVM_EXPORT_TEMPLATE ExceptionSectionEntry<support::ubig32_t>;
+template struct LLVM_EXPORT_TEMPLATE ExceptionSectionEntry<support::ubig64_t>;
 
 template <typename T>
 Expected<StringRef> getLoaderSecSymNameInStrTbl(const T *LoaderSecHeader,
@@ -1375,11 +1375,11 @@ Expected<StringRef> XCOFFSymbolRef::getName() const {
 }
 
 // Explicitly instantiate template classes.
-template struct XCOFFSectionHeader<XCOFFSectionHeader32>;
-template struct XCOFFSectionHeader<XCOFFSectionHeader64>;
+template struct LLVM_EXPORT_TEMPLATE XCOFFSectionHeader<XCOFFSectionHeader32>;
+template struct LLVM_EXPORT_TEMPLATE XCOFFSectionHeader<XCOFFSectionHeader64>;
 
-template struct XCOFFRelocation<llvm::support::ubig32_t>;
-template struct XCOFFRelocation<llvm::support::ubig64_t>;
+template struct LLVM_EXPORT_TEMPLATE XCOFFRelocation<llvm::support::ubig32_t>;
+template struct LLVM_EXPORT_TEMPLATE XCOFFRelocation<llvm::support::ubig64_t>;
 
 template LLVM_EXPORT_TEMPLATE
     llvm::Expected<llvm::ArrayRef<llvm::object::XCOFFRelocation64>>
-- 
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