Compiler checks must use per-subproject options

Fixes: #12202

mesonbuild/interpreter/compiler.py

@@ -261,7 +261,7 @@ class CompilerHolder(ObjectHolder['Compiler']):
             for idir in i.to_string_list(self.environment.get_source_dir(), self.environment.get_build_dir()):
                 args.extend(self.compiler.get_include_args(idir, False))
         if not kwargs['no_builtin_args']:
-            opts = self.environment.coredata.options
+            opts = coredata.OptionsView(self.environment.coredata.options, self.subproject)
             args += self.compiler.get_option_compile_args(opts)
             if mode is CompileCheckMode.LINK:
                 args.extend(self.compiler.get_option_link_args(opts))

test cases/common/223 persubproject options/subprojects/sub2/meson.build

@@ -14,3 +14,7 @@ shared_library('lib1', 'foo.c')
 # Parent project is c++11 but this one uses c++14 to build.
 libcpp14 = library('lib2', 'foo.cpp')
 meson.override_dependency('libcpp14', declare_dependency(link_with: libcpp14))
+
+# Compiler checks should be using c++14 as well
+cxx = meson.get_compiler('cpp')
+assert(cxx.compiles(files('foo.cpp')))