[libcxx, libcxxabi, libunwind] Prefer -fvisibility-global-new-delete=force-hidden

[mstorsjo]

27ce26b added the new option -fvisibility-global-new-delete=, where
-fvisibility-global-new-delete=force-hidden is equivalent to the old option -fvisibility-global-new-delete-hidden. At the same time, the old option was deprecated.

Test for and use the new option form first; if unsupported, try using the old form.

This avoids warnings in the MinGW builds, if built with Clang 18 or newer.

[llvmbot]

@llvm/pr-subscribers-libunwind
@llvm/pr-subscribers-libcxxabi

@llvm/pr-subscribers-libcxx

Author: Martin Storsjö (mstorsjo)

Changes

27ce26b added the new option -fvisibility-global-new-delete=, where
-fvisibility-global-new-delete=force-hidden is equivalent to the old option -fvisibility-global-new-delete-hidden. At the same time, the old option was deprecated.

Test for and use the new option form first; if unsupported, try using the old form.

This avoids warnings in the MinGW builds, if built with Clang 18 or newer.

---

Full diff: https://github.com/llvm/llvm-project/pull/84917.diff

3 Files Affected:

• (modified) libcxx/src/CMakeLists.txt (+4-1)
• (modified) libcxxabi/src/CMakeLists.txt (+4-1)
• (modified) libunwind/src/CMakeLists.txt (+4-1)

diff --git a/libcxx/src/CMakeLists.txt b/libcxx/src/CMakeLists.txt
index 07ffc8bfdaae3d..1110a79ddcacd5 100644
--- a/libcxx/src/CMakeLists.txt
+++ b/libcxx/src/CMakeLists.txt
@@ -301,7 +301,10 @@ if (LIBCXX_ENABLE_STATIC)
     # then its code shouldn't declare them with hidden visibility.  They might
     # actually be provided by a shared library at link time.
     if (LIBCXX_ENABLE_NEW_DELETE_DEFINITIONS)
-      append_flags_if_supported(CXX_STATIC_LIBRARY_FLAGS -fvisibility-global-new-delete-hidden)
+      append_flags_if_supported(CXX_STATIC_LIBRARY_FLAGS -fvisibility-global-new-delete=force-hidden)
+      if (NOT CXX_SUPPORTS_FVISIBILITY_GLOBAL_NEW_DELETE_EQ_FORCE_HIDDEN_FLAG)
+        append_flags_if_supported(CXX_STATIC_LIBRARY_FLAGS -fvisibility-global-new-delete-hidden)
+      endif()
     endif()
     target_compile_options(cxx_static PRIVATE ${CXX_STATIC_LIBRARY_FLAGS})
     # _LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS can be defined in __config_site
diff --git a/libcxxabi/src/CMakeLists.txt b/libcxxabi/src/CMakeLists.txt
index 0af4dc1448e91a..c8cc93de50777b 100644
--- a/libcxxabi/src/CMakeLists.txt
+++ b/libcxxabi/src/CMakeLists.txt
@@ -268,7 +268,10 @@ if(LIBCXXABI_HERMETIC_STATIC_LIBRARY)
   # then its code shouldn't declare them with hidden visibility.  They might
   # actually be provided by a shared library at link time.
   if (LIBCXXABI_ENABLE_NEW_DELETE_DEFINITIONS)
-    target_add_compile_flags_if_supported(cxxabi_static_objects PRIVATE -fvisibility-global-new-delete-hidden)
+    target_add_compile_flags_if_supported(cxxabi_static_objects PRIVATE -fvisibility-global-new-delete=force-hidden)
+    if (NOT CXX_SUPPORTS_FVISIBILITY_GLOBAL_NEW_DELETE_EQ_FORCE_HIDDEN_FLAG)
+      target_add_compile_flags_if_supported(cxxabi_static_objects PRIVATE -fvisibility-global-new-delete-hidden)
+    endif()
   endif()
   # _LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS can be defined in libcxx's
   # __config_site too. Define it in the same way here, to avoid redefinition
diff --git a/libunwind/src/CMakeLists.txt b/libunwind/src/CMakeLists.txt
index 9c6f5d908b0945..780430ba70ba60 100644
--- a/libunwind/src/CMakeLists.txt
+++ b/libunwind/src/CMakeLists.txt
@@ -201,7 +201,10 @@ set_target_properties(unwind_static_objects
 
 if(LIBUNWIND_HIDE_SYMBOLS)
   target_add_compile_flags_if_supported(unwind_static_objects PRIVATE -fvisibility=hidden)
-  target_add_compile_flags_if_supported(unwind_static_objects PRIVATE -fvisibility-global-new-delete-hidden)
+  target_add_compile_flags_if_supported(unwind_static_objects PRIVATE -fvisibility-global-new-delete=force-hidden)
+  if (NOT CXX_SUPPORTS_FVISIBILITY_GLOBAL_NEW_DELETE_EQ_FORCE_HIDDEN_FLAG)
+    target_add_compile_flags_if_supported(unwind_static_objects PRIVATE -fvisibility-global-new-delete-hidden)
+  endif()
   target_compile_definitions(unwind_static_objects PRIVATE _LIBUNWIND_HIDE_SYMBOLS)
 endif()
 

[ldionne]

/cherry-pick 1f973ef

[llvmbot]

/pull-request #85126