The previous placement resulted in this warning when using g++-13:
/home/david.spickett/llvm-project/llvm/include/llvm/Support/Compiler.h:120:43: warning: attribute ignored [-Wattributes]
120 | #define LLVM_ATTRIBUTE_VISIBILITY_DEFAULT [[gnu::visibility("default")]]
| ^
/home/david.spickett/llvm-project/llvm/include/llvm/Support/Compiler.h:213:18: note: in expansion of macro ‘LLVM_ATTRIBUTE_VISIBILITY_DEFAULT’
213 | #define LLVM_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/david.spickett/llvm-project/llvm/lib/ProfileData/MemProfRadixTree.cpp:245:5: note: in expansion of macro ‘LLVM_ABI’
245 | LLVM_ABI computeFrameHistogram<FrameId>(
| ^~~~~~~~
/home/david.spickett/llvm-project/llvm/include/llvm/Support/Compiler.h:120:43: note: an attribute that appertains to a type-specifier is ignored
120 | #define LLVM_ATTRIBUTE_VISIBILITY_DEFAULT [[gnu::visibility("default")]]
| ^
According to the interface guide, that macro should go before the return
type to be effective.
https://llvm.org/docs/InterfaceExportAnnotations.html#specialized-template-functions
## Purpose
This patch is one in a series of code-mods that annotate LLVM’s public
interface for export. This patch annotates the `llvm/ProfileData`
library. 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:
- Manually annotate the file
`llvm/include/llvm/ProfileData/InstrProfData.inc` because it is skipped
by IDS
- Add `LLVM_TEMPLATE_ABI` and `LLVM_EXPORT_TEMPLATE` to exported
instantiated templates.
- Add `LLVM_ABI_FRIEND` to friend member functions declared with
`LLVM_ABI`
- Add `LLVM_ABI` to a small number of symbols that require export but
are not declared in headers
## 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
