Conditionally check the compiler flags in libs.native (#109228)

Author: am11

src/native/libs/CMakeLists.txt

@@ -126,10 +126,14 @@ if (CLR_CMAKE_TARGET_UNIX OR CLR_CMAKE_TARGET_BROWSER OR CLR_CMAKE_TARGET_WASI)
         add_compile_options(-Wno-empty-translation-unit)
         add_compile_options(-Wno-cast-align)
         add_compile_options(-Wno-typedef-redefinition)
-        add_compile_options(-Wno-c11-extensions)
-        add_compile_options(-Wno-pre-c11-compat) # fixes build on Debian
-        add_compile_options(-Wno-unknown-warning-option) # unknown warning option '-Wno-pre-c11-compat'
         add_compile_options(-Wno-thread-safety-analysis)
+        add_compile_options(-Wno-c11-extensions)
+
+        check_c_compiler_flag(-Wpre-c11-compat COMPILER_SUPPORTS_W_PRE_C11_COMPAT)
+        if (COMPILER_SUPPORTS_W_PRE_C11_COMPAT)
+            add_compile_options(-Wno-pre-c11-compat)
+        endif()
+
         if (CLR_CMAKE_TARGET_BROWSER OR CLR_CMAKE_TARGET_WASI)
             add_compile_options(-Wno-unsafe-buffer-usage)
             add_compile_options(-Wno-cast-function-type-strict)