[release/7.0] Suppress clang-16 warnings (backport #81573) (#84444)

Fix DBI loading problem on Linux (#82461)

Author: ayakael

eng/native/configurecompiler.cmake

@@ -449,6 +449,15 @@ if (CLR_CMAKE_HOST_UNIX)
     add_compile_options(-Wno-incompatible-ms-struct)
 
     add_compile_options(-Wno-reserved-identifier)
+
+    # clang 16.0 introduced buffer hardening https://discourse.llvm.org/t/rfc-c-buffer-hardening/65734
+    # which we are not conforming to yet.
+    add_compile_options(-Wno-unsafe-buffer-usage)
+
+    # other clang 16.0 suppressions
+    add_compile_options(-Wno-single-bit-bitfield-constant-conversion)
+    add_compile_options(-Wno-cast-function-type-strict)
+    add_compile_options(-Wno-incompatible-function-pointer-types-strict)
   else()
     add_compile_options(-Wno-uninitialized)
     add_compile_options(-Wno-strict-aliasing)

src/coreclr/dlls/mscordbi/CMakeLists.txt

@@ -100,6 +100,17 @@ elseif(CLR_CMAKE_HOST_UNIX)
         mscordaccore
     )
 
+    # Before llvm 16, lld was setting `--undefined-version` by default. The default was
+    # flipped to `--no-undefined-version` in lld 16, so we will explicitly set it to
+    # `--undefined-version` for our use-case.
+    include(CheckLinkerFlag OPTIONAL)
+    if(COMMAND check_linker_flag)
+        check_linker_flag(CXX -Wl,--undefined-version LINKER_SUPPORTS_UNDEFINED_VERSION)
+        if (LINKER_SUPPORTS_UNDEFINED_VERSION)
+            add_linker_flag(-Wl,--undefined-version)
+        endif(LINKER_SUPPORTS_UNDEFINED_VERSION)
+    endif(COMMAND check_linker_flag)
+
     # COREDBI_LIBRARIES is mentioned twice because ld is one pass linker and will not find symbols
     # if they are defined after they are used. Having all libs twice makes sure that ld will actually
     # find all symbols.

src/native/corehost/apphost/static/CMakeLists.txt

@@ -65,8 +65,8 @@ if(CLR_CMAKE_TARGET_WIN32)
     add_linker_flag("/DEF:${CMAKE_CURRENT_SOURCE_DIR}/singlefilehost.def")
 
 else()
-    if(CLR_CMAKE_TARGET_OSX)
-        set(DEF_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/singlefilehost_OSXexports.src)
+    if(CLR_CMAKE_TARGET_FREEBSD)
+        set(DEF_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/singlefilehost_freebsdexports.src)
     else()
         set(DEF_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/singlefilehost_unixexports.src)
     endif()

src/native/corehost/apphost/static/singlefilehost_OSXexports.src renamed to src/native/corehost/apphost/static/singlefilehost_freebsdexports.src

@@ -9,3 +9,7 @@ g_dacTable
 
 ; Used by profilers
 MetaDataGetDispenser
+
+; FreeBSD needs to reexport these
+__progname
+environ 

src/native/corehost/apphost/static/singlefilehost_unixexports.src

@@ -9,7 +9,3 @@ g_dacTable
 
 ; Used by profilers
 MetaDataGetDispenser
-
-; FreeBSD needs to reexport these
-__progname
-environ