compilers: make keyword args to Compiler.compile keyword only

Becuase treating args as either keyword or positional makes inheritance
really awful to work with.

mesonbuild/compilers/clike.py

@@ -849,7 +849,7 @@ class CLikeCompiler:
         '''
         args = self.get_compiler_check_args()
         n = 'symbols_have_underscore_prefix'
-        with self.compile(code, args, 'compile', want_output=True) as p:
+        with self.compile(code, extra_args=args, mode='compile', want_output=True) as p:
             if p.returncode != 0:
                 m = 'BUG: Unable to compile {!r} check: {}'
                 raise RuntimeError(m.format(n, p.stdo))

mesonbuild/compilers/compilers.py

@@ -1146,7 +1146,7 @@ class Compiler:
         return os.path.join(dirname, 'output.' + suffix)
 
     @contextlib.contextmanager
-    def compile(self, code, extra_args=None, mode='link', want_output=False):
+    def compile(self, code, extra_args=None, *, mode='link', want_output=False):
         if extra_args is None:
             extra_args = []
         try:
@@ -1199,7 +1199,7 @@ class Compiler:
             pass
 
     @contextlib.contextmanager
-    def cached_compile(self, code, cdata: coredata.CoreData, extra_args=None, mode: str = 'link'):
+    def cached_compile(self, code, cdata: coredata.CoreData, *, extra_args=None, mode: str = 'link'):
         assert(isinstance(cdata, coredata.CoreData))
 
         # Calculate the key

mesonbuild/compilers/cpp.py

@@ -97,7 +97,7 @@ class CPPCompiler(CLikeCompiler, Compiler):
         # 2. even if it did have an env object, that might contain another more
         #    recent -std= argument, which might lead to a cascaded failure.
         CPP_TEST = 'int i = static_cast<int>(0);'
-        with self.compile(code=CPP_TEST, extra_args=[cpp_std_value], mode='compile') as p:
+        with self.compile(CPP_TEST, extra_args=[cpp_std_value], mode='compile') as p:
             if p.returncode == 0:
                 mlog.debug('Compiler accepts {}:'.format(cpp_std_value), 'YES')
                 return True