[llvm] [Libomptarget] Pass '-Werror=global-constructors' to the libomptarget build (PR #88531)

[Joseph Huber via llvm-commits]

https://github.com/jhuber6 updated https://github.com/llvm/llvm-project/pull/88531

>From 75f74188ae10e1180bcd8cf1a37af669fb071a97 Mon Sep 17 00:00:00 2001
From: Joseph Huber <huberjn at outlook.com>
Date: Fri, 12 Apr 2024 11:03:18 -0500
Subject: [PATCH] [Libomptarget] Pass '-Werror=global-constructors' to the
 libomptarget build

Summary:
A runtime library should not have global constructors. This has caused
many issues in the past so we would make them a hard error if they show
up. This required rewriting the RecordReplay implementation because it
uses a SmallVector internally which can't be made constexpr.
---
 offload/CMakeLists.txt     | 5 +++++
 offload/src/CMakeLists.txt | 4 ++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/offload/CMakeLists.txt b/offload/CMakeLists.txt
index 1d8cab240924e..e2a4c2597636e 100644
--- a/offload/CMakeLists.txt
+++ b/offload/CMakeLists.txt
@@ -136,6 +136,8 @@ include(LibomptargetGetDependencies)
 # Set up testing infrastructure.
 include(OpenMPTesting)
 
+check_cxx_compiler_flag(-Werror=global-constructors OFFLOAD_HAVE_WERROR_CTOR)
+
 # LLVM source tree is required at build time for libomptarget
 if (NOT LIBOMPTARGET_LLVM_INCLUDE_DIRS)
   message(FATAL_ERROR "Missing definition for LIBOMPTARGET_LLVM_INCLUDE_DIRS")
@@ -207,6 +209,9 @@ set(offload_compile_flags -fno-exceptions)
 if(NOT LLVM_ENABLE_RTTI)
   set(offload_compile_flags ${offload_compile_flags} -fno-rtti)
 endif()
+if(OFFLOAD_HAVE_WERROR_CTOR)
+  list(APPEND offload_compile_flags -Werror=global-constructors)
+endif()
 
 # TODO: Consider enabling LTO by default if supported.
 # https://cmake.org/cmake/help/latest/module/CheckIPOSupported.html can be used
diff --git a/offload/src/CMakeLists.txt b/offload/src/CMakeLists.txt
index b474f29ea0be2..c5338130297fe 100644
--- a/offload/src/CMakeLists.txt
+++ b/offload/src/CMakeLists.txt
@@ -69,8 +69,8 @@ foreach(plugin IN LISTS LIBOMPTARGET_PLUGINS_TO_BUILD)
   target_link_libraries(omptarget PRIVATE omptarget.rtl.${plugin})
 endforeach()
 
-target_compile_options(omptarget PUBLIC ${offload_compile_flags})
-target_link_options(omptarget PUBLIC ${offload_link_flags})
+target_compile_options(omptarget PRIVATE ${offload_compile_flags})
+target_link_options(omptarget PRIVATE ${offload_link_flags})
 
 # libomptarget.so needs to be aware of where the plugins live as they
 # are now separated in the build directory.