Replace some type comments with annotations

9 files changed, 119 insertions, 115 deletions

diff --git a/mesonbuild/compilers/mixins/ccrx.py b/mesonbuild/compilers/mixins/ccrx.py
index 1c22214..6e503d1 100644
--- a/mesonbuild/compilers/mixins/ccrx.py
+++ b/mesonbuild/compilers/mixins/ccrx.py
@@ -31,35 +31,35 @@ else:
     # do). This gives up DRYer type checking, with no runtime impact
     Compiler = object
 
-ccrx_buildtype_args = {
+ccrx_buildtype_args: T.Dict[str, T.List[str]] = {
     'plain': [],
     'debug': [],
     'debugoptimized': [],
     'release': [],
     'minsize': [],
     'custom': [],
-}  # type: T.Dict[str, T.List[str]]
+}
 
-ccrx_optimization_args = {
+ccrx_optimization_args: T.Dict[str, T.List[str]] = {
     '0': ['-optimize=0'],
     'g': ['-optimize=0'],
     '1': ['-optimize=1'],
     '2': ['-optimize=2'],
     '3': ['-optimize=max'],
     's': ['-optimize=2', '-size']
-}  # type: T.Dict[str, T.List[str]]
+}
 
-ccrx_debug_args = {
+ccrx_debug_args: T.Dict[bool, T.List[str]] = {
     False: [],
     True: ['-debug']
-}  # type: T.Dict[bool, T.List[str]]
+}
 
 
 class CcrxCompiler(Compiler):
 
     if T.TYPE_CHECKING:
         is_cross = True
-        can_compile_suffixes = set()  # type: T.Set[str]
+        can_compile_suffixes: T.Set[str] = set()
 
     id = 'ccrx'
 
@@ -68,12 +68,13 @@ class CcrxCompiler(Compiler):
             raise EnvironmentException('ccrx supports only cross-compilation.')
         # Assembly
         self.can_compile_suffixes.add('src')
-        default_warn_args = []  # type: T.List[str]
-        self.warn_args = {'0': [],
-                          '1': default_warn_args,
-                          '2': default_warn_args + [],
-                          '3': default_warn_args + [],
-                          'everything': default_warn_args + []}  # type: T.Dict[str, T.List[str]]
+        default_warn_args: T.List[str] = []
+        self.warn_args: T.Dict[str, T.List[str]] = {
+            '0': [],
+            '1': default_warn_args,
+            '2': default_warn_args + [],
+            '3': default_warn_args + [],
+            'everything': default_warn_args + []}
 
     def get_pic_args(self) -> T.List[str]:
         # PIC support is not enabled by default for CCRX,
diff --git a/mesonbuild/compilers/mixins/clang.py b/mesonbuild/compilers/mixins/clang.py
index b43b246..24f24a8 100644
--- a/mesonbuild/compilers/mixins/clang.py
+++ b/mesonbuild/compilers/mixins/clang.py
@@ -30,13 +30,13 @@ if T.TYPE_CHECKING:
     from ...environment import Environment
     from ...dependencies import Dependency  # noqa: F401
 
-clang_color_args = {
+clang_color_args: T.Dict[str, T.List[str]] = {
     'auto': ['-fcolor-diagnostics'],
     'always': ['-fcolor-diagnostics'],
     'never': ['-fno-color-diagnostics'],
-}  # type: T.Dict[str, T.List[str]]
+}
 
-clang_optimization_args = {
+clang_optimization_args: T.Dict[str, T.List[str]] = {
     'plain': [],
     '0': ['-O0'],
     'g': ['-Og'],
@@ -44,7 +44,7 @@ clang_optimization_args = {
     '2': ['-O2'],
     '3': ['-O3'],
     's': ['-Oz'],
-}  # type: T.Dict[str, T.List[str]]
+}
 
 class ClangCompiler(GnuLikeCompiler):
 
diff --git a/mesonbuild/compilers/mixins/clike.py b/mesonbuild/compilers/mixins/clike.py
index fe39ef1..d3e1008 100644
--- a/mesonbuild/compilers/mixins/clike.py
+++ b/mesonbuild/compilers/mixins/clike.py
@@ -103,7 +103,7 @@ class CLikeCompilerArgs(arglist.CompilerArgs):
         default_dirs = self.compiler.get_default_include_dirs()
         if default_dirs:
             real_default_dirs = [self._cached_realpath(i) for i in default_dirs]
-            bad_idx_list = []  # type: T.List[int]
+            bad_idx_list: T.List[int] = []
             for i, each in enumerate(new):
                 if not each.startswith('-isystem'):
                     continue
@@ -136,11 +136,11 @@ class CLikeCompiler(Compiler):
     """Shared bits for the C and CPP Compilers."""
 
     if T.TYPE_CHECKING:
-        warn_args = {}  # type: T.Dict[str, T.List[str]]
+        warn_args: T.Dict[str, T.List[str]] = {}
 
     # TODO: Replace this manual cache with functools.lru_cache
-    find_library_cache = {}    # type: T.Dict[T.Tuple[T.Tuple[str, ...], str, T.Tuple[str, ...], str, LibType], T.Optional[T.List[str]]]
-    find_framework_cache = {}  # type: T.Dict[T.Tuple[T.Tuple[str, ...], str, T.Tuple[str, ...], bool], T.Optional[T.List[str]]]
+    find_library_cache: T.Dict[T.Tuple[T.Tuple[str, ...], str, T.Tuple[str, ...], str, LibType], T.Optional[T.List[str]]] = {}
+    find_framework_cache: T.Dict[T.Tuple[T.Tuple[str, ...], str, T.Tuple[str, ...], bool], T.Optional[T.List[str]]] = {}
     internal_libs = arglist.UNIXY_COMPILER_INTERNAL_LIBS
 
     def __init__(self, exe_wrapper: T.Optional['ExternalProgram'] = None):
@@ -389,8 +389,8 @@ class CLikeCompiler(Compiler):
                              dependencies=dependencies)
 
     def _get_basic_compiler_args(self, env: 'Environment', mode: CompileCheckMode) -> T.Tuple[T.List[str], T.List[str]]:
-        cargs = []  # type: T.List[str]
-        largs = []  # type: T.List[str]
+        cargs: T.List[str] = []
+        largs: T.List[str] = []
         if mode is CompileCheckMode.LINK:
             # Sometimes we need to manually select the CRT to use with MSVC.
             # One example is when trying to do a compiler check that involves
@@ -446,8 +446,8 @@ class CLikeCompiler(Compiler):
             # TODO: we want to ensure the front end does the listifing here
             dependencies = [dependencies]
         # Collect compiler arguments
-        cargs = self.compiler_args()  # type: arglist.CompilerArgs
-        largs = []  # type: T.List[str]
+        cargs: arglist.CompilerArgs = self.compiler_args()
+        largs: T.List[str] = []
         for d in dependencies:
             # Add compile flags needed by dependencies
             cargs += d.get_compile_args()
@@ -805,7 +805,7 @@ class CLikeCompiler(Compiler):
         #
         # class StrProto(typing.Protocol):
         #    def __str__(self) -> str: ...
-        fargs = {'prefix': prefix, 'func': funcname}  # type: T.Dict[str, T.Union[str, bool, int]]
+        fargs: T.Dict[str, T.Union[str, bool, int]] = {'prefix': prefix, 'func': funcname}
 
         # glibc defines functions that are not available on Linux as stubs that
         # fail with ENOSYS (such as e.g. lchmod). In this case we want to fail
@@ -1002,7 +1002,7 @@ class CLikeCompiler(Compiler):
         return self._symbols_have_underscore_prefix_searchbin(env)
 
     def _get_patterns(self, env: 'Environment', prefixes: T.List[str], suffixes: T.List[str], shared: bool = False) -> T.List[str]:
-        patterns = []  # type: T.List[str]
+        patterns: T.List[str] = []
         for p in prefixes:
             for s in suffixes:
                 patterns.append(p + '{}.' + s)
@@ -1066,7 +1066,7 @@ class CLikeCompiler(Compiler):
 
     @staticmethod
     def _sort_shlibs_openbsd(libs: T.List[str]) -> T.List[str]:
-        filtered = []  # type: T.List[str]
+        filtered: T.List[str] = []
         for lib in libs:
             # Validate file as a shared library of type libfoo.so.X.Y
             ret = lib.rsplit('.so.', maxsplit=1)
@@ -1205,7 +1205,7 @@ class CLikeCompiler(Compiler):
         os_env = os.environ.copy()
         os_env['LC_ALL'] = 'C'
         _, _, stde = mesonlib.Popen_safe(commands, env=os_env, stdin=subprocess.PIPE)
-        paths = []  # T.List[str]
+        paths: T.List[str] = []
         for line in stde.split('\n'):
             if '(framework directory)' not in line:
                 continue
@@ -1273,7 +1273,7 @@ class CLikeCompiler(Compiler):
         return self.compiles(code, env, extra_args=args, mode=mode)
 
     def _has_multi_arguments(self, args: T.List[str], env: 'Environment', code: str) -> T.Tuple[bool, bool]:
-        new_args = []  # type: T.List[str]
+        new_args: T.List[str] = []
         for arg in args:
             # some compilers, e.g. GCC, don't warn for unsupported warning-disable
             # flags, so when we are testing a flag like "-Wno-forgotten-towel", also
diff --git a/mesonbuild/compilers/mixins/compcert.py b/mesonbuild/compilers/mixins/compcert.py
index d9c21a8..ac4d5aa 100644
--- a/mesonbuild/compilers/mixins/compcert.py
+++ b/mesonbuild/compilers/mixins/compcert.py
@@ -30,16 +30,16 @@ else:
     # do). This gives up DRYer type checking, with no runtime impact
     Compiler = object
 
-ccomp_buildtype_args = {
+ccomp_buildtype_args: T.Dict[str, T.List[str]] = {
     'plain': [''],
     'debug': ['-O0', '-g'],
     'debugoptimized': ['-O0', '-g'],
     'release': ['-O3'],
     'minsize': ['-Os'],
     'custom': ['-Obranchless'],
-}  # type: T.Dict[str, T.List[str]]
+}
 
-ccomp_optimization_args = {
+ccomp_optimization_args: T.Dict[str, T.List[str]] = {
     'plain': [],
     '0': ['-O0'],
     'g': ['-O0'],
@@ -47,19 +47,19 @@ ccomp_optimization_args = {
     '2': ['-O2'],
     '3': ['-O3'],
     's': ['-Os']
-}  # type: T.Dict[str, T.List[str]]
+}
 
-ccomp_debug_args = {
+ccomp_debug_args: T.Dict[bool, T.List[str]] = {
     False: [],
     True: ['-g']
-}  # type: T.Dict[bool, T.List[str]]
+}
 
 # As of CompCert 20.04, these arguments should be passed to the underlying gcc linker (via -WUl,<arg>)
 # There are probably (many) more, but these are those used by picolibc
-ccomp_args_to_wul = [
+ccomp_args_to_wul: T.List[str] = [
         r"^-ffreestanding$",
         r"^-r$"
-] # type: T.List[str]
+]
 
 class CompCertCompiler(Compiler):
 
@@ -69,12 +69,13 @@ class CompCertCompiler(Compiler):
         # Assembly
         self.can_compile_suffixes.add('s')
         self.can_compile_suffixes.add('sx')
-        default_warn_args = []  # type: T.List[str]
-        self.warn_args = {'0': [],
-                          '1': default_warn_args,
-                          '2': default_warn_args + [],
-                          '3': default_warn_args + [],
-                          'everything': default_warn_args + []}  # type: T.Dict[str, T.List[str]]
+        default_warn_args: T.List[str] = []
+        self.warn_args: T.Dict[str, T.List[str]] = {
+            '0': [],
+            '1': default_warn_args,
+            '2': default_warn_args + [],
+            '3': default_warn_args + [],
+            'everything': default_warn_args + []}
 
     def get_always_args(self) -> T.List[str]:
         return []
@@ -95,7 +96,7 @@ class CompCertCompiler(Compiler):
     @classmethod
     def _unix_args_to_native(cls, args: T.List[str], info: MachineInfo) -> T.List[str]:
         "Always returns a copy that can be independently mutated"
-        patched_args = []  # type: T.List[str]
+        patched_args: T.List[str] = []
         for arg in args:
             added = 0
             for ptrn in ccomp_args_to_wul:
diff --git a/mesonbuild/compilers/mixins/gnu.py b/mesonbuild/compilers/mixins/gnu.py
index 6517a3e..703fb1a 100644
--- a/mesonbuild/compilers/mixins/gnu.py
+++ b/mesonbuild/compilers/mixins/gnu.py
@@ -42,21 +42,21 @@ else:
 
 # XXX: prevent circular references.
 # FIXME: this really is a posix interface not a c-like interface
-clike_debug_args = {
+clike_debug_args: T.Dict[bool, T.List[str]] = {
     False: [],
     True: ['-g'],
-}  # type: T.Dict[bool, T.List[str]]
+}
 
-gnulike_buildtype_args = {
+gnulike_buildtype_args: T.Dict[str, T.List[str]] = {
     'plain': [],
     'debug': [],
     'debugoptimized': [],
     'release': [],
     'minsize': [],
     'custom': [],
-}  # type: T.Dict[str, T.List[str]]
+}
 
-gnu_optimization_args = {
+gnu_optimization_args: T.Dict[str, T.List[str]] = {
     'plain': [],
     '0': ['-O0'],
     'g': ['-Og'],
@@ -64,9 +64,9 @@ gnu_optimization_args = {
     '2': ['-O2'],
     '3': ['-O3'],
     's': ['-Os'],
-}  # type: T.Dict[str, T.List[str]]
+}
 
-gnulike_instruction_set_args = {
+gnulike_instruction_set_args: T.Dict[str, T.List[str]] = {
     'mmx': ['-mmmx'],
     'sse': ['-msse'],
     'sse2': ['-msse2'],
@@ -77,22 +77,22 @@ gnulike_instruction_set_args = {
     'avx': ['-mavx'],
     'avx2': ['-mavx2'],
     'neon': ['-mfpu=neon'],
-}  # type: T.Dict[str, T.List[str]]
+}
 
-gnu_symbol_visibility_args = {
+gnu_symbol_visibility_args: T.Dict[str, T.List[str]] = {
     '': [],
     'default': ['-fvisibility=default'],
     'internal': ['-fvisibility=internal'],
     'hidden': ['-fvisibility=hidden'],
     'protected': ['-fvisibility=protected'],
     'inlineshidden': ['-fvisibility=hidden', '-fvisibility-inlines-hidden'],
-}  # type: T.Dict[str, T.List[str]]
+}
 
-gnu_color_args = {
+gnu_color_args: T.Dict[str, T.List[str]] = {
     'auto': ['-fdiagnostics-color=auto'],
     'always': ['-fdiagnostics-color=always'],
     'never': ['-fdiagnostics-color=never'],
-}  # type: T.Dict[str, T.List[str]]
+}
 
 # Warnings collected from the GCC source and documentation.  This is an
 # objective set of all the warnings flags that apply to general projects: the
@@ -118,7 +118,7 @@ gnu_color_args = {
 #
 # Omitted warnings enabled elsewhere in meson:
 #   -Winvalid-pch (GCC 3.4.0)
-gnu_common_warning_args = {
+gnu_common_warning_args: T.Dict[str, T.List[str]] = {
     "0.0.0": [
         "-Wcast-qual",
         "-Wconversion",
@@ -213,7 +213,7 @@ gnu_common_warning_args = {
         "-Wopenacc-parallelism",
         "-Wtrivial-auto-var-init",
     ],
-}  # type: T.Dict[str, T.List[str]]
+}
 
 # GCC warnings for C
 # Omitted non-general or legacy warnings:
@@ -223,7 +223,7 @@ gnu_common_warning_args = {
 #   -Wdeclaration-after-statement
 #   -Wtraditional
 #   -Wtraditional-conversion
-gnu_c_warning_args = {
+gnu_c_warning_args: T.Dict[str, T.List[str]] = {
     "0.0.0": [
         "-Wbad-function-cast",
         "-Wmissing-prototypes",
@@ -240,7 +240,7 @@ gnu_c_warning_args = {
     "4.5.0": [
         "-Wunsuffixed-float-constants",
     ],
-}  # type: T.Dict[str, T.List[str]]
+}
 
 # GCC warnings for C++
 # Omitted non-general or legacy warnings:
@@ -250,7 +250,7 @@ gnu_c_warning_args = {
 #   -Wctad-maybe-unsupported
 #   -Wnamespaces
 #   -Wtemplates
-gnu_cpp_warning_args = {
+gnu_cpp_warning_args: T.Dict[str, T.List[str]] = {
     "0.0.0": [
         "-Wctor-dtor-privacy",
         "-Weffc++",
@@ -309,13 +309,13 @@ gnu_cpp_warning_args = {
         "-Wdeprecated-enum-float-conversion",
         "-Winvalid-imported-macros",
     ],
-}  # type: T.Dict[str, T.List[str]]
+}
 
 # GCC warnings for Objective C and Objective C++
 # Omitted non-general or legacy warnings:
 #   -Wtraditional
 #   -Wtraditional-conversion
-gnu_objc_warning_args = {
+gnu_objc_warning_args: T.Dict[str, T.List[str]] = {
     "0.0.0": [
         "-Wselector",
     ],
@@ -326,7 +326,7 @@ gnu_objc_warning_args = {
         "-Wassign-intercept",
         "-Wstrict-selector-match",
     ],
-}  # type: T.Dict[str, T.List[str]]
+}
 
 _LANG_MAP = {
     'c': 'c',
@@ -345,7 +345,7 @@ def gnulike_default_include_dirs(compiler: T.Tuple[str, ...], lang: str) -> 'Imm
     cmd = list(compiler) + [f'-x{lang}', '-E', '-v', '-']
     _, stdout, _ = mesonlib.Popen_safe(cmd, stderr=subprocess.STDOUT, env=env)
     parse_state = 0
-    paths = []  # type: T.List[str]
+    paths: T.List[str] = []
     for line in stdout.split('\n'):
         line = line.strip(' \n\r\t')
         if parse_state == 0:
diff --git a/mesonbuild/compilers/mixins/intel.py b/mesonbuild/compilers/mixins/intel.py
index b793fa8..711e77c 100644
--- a/mesonbuild/compilers/mixins/intel.py
+++ b/mesonbuild/compilers/mixins/intel.py
@@ -50,14 +50,14 @@ class IntelGnuLikeCompiler(GnuLikeCompiler):
     minsize: -O2
     """
 
-    BUILD_ARGS = {
+    BUILD_ARGS: T.Dict[str, T.List[str]] = {
         'plain': [],
         'debug': ["-g", "-traceback"],
         'debugoptimized': ["-g", "-traceback"],
         'release': [],
         'minsize': [],
         'custom': [],
-    }  # type: T.Dict[str, T.List[str]]
+    }
 
     OPTIM_ARGS: T.Dict[str, T.List[str]] = {
         'plain': [],
@@ -129,14 +129,14 @@ class IntelVisualStudioLikeCompiler(VisualStudioLikeCompiler):
 
     """Abstractions for ICL, the Intel compiler on Windows."""
 
-    BUILD_ARGS = {
+    BUILD_ARGS: T.Dict[str, T.List[str]] = {
         'plain': [],
         'debug': ["/Zi", "/traceback"],
         'debugoptimized': ["/Zi", "/traceback"],
         'release': [],
         'minsize': [],
         'custom': [],
-    }  # type: T.Dict[str, T.List[str]]
+    }
 
     OPTIM_ARGS: T.Dict[str, T.List[str]] = {
         'plain': [],
diff --git a/mesonbuild/compilers/mixins/metrowerks.py b/mesonbuild/compilers/mixins/metrowerks.py
index 4390145..970faeb 100644
--- a/mesonbuild/compilers/mixins/metrowerks.py
+++ b/mesonbuild/compilers/mixins/metrowerks.py
@@ -30,16 +30,16 @@ else:
     # do). This gives up DRYer type checking, with no runtime impact
     Compiler = object
 
-mwcc_buildtype_args = {
+mwcc_buildtype_args: T.Dict[str, T.List[str]] = {
     'plain': [],
     'debug': ['-g'],
     'debugoptimized': ['-g', '-O4'],
     'release': ['-O4,p'],
     'minsize': ['-Os'],
     'custom': [],
-}  # type: T.Dict[str, T.List[str]]
+}
 
-mwccarm_instruction_set_args = {
+mwccarm_instruction_set_args: T.Dict[str, T.List[str]] = {
     'generic': ['-proc', 'generic'],
     'v4': ['-proc', 'v4'],
     'v4t': ['-proc', 'v4t'],
@@ -69,9 +69,9 @@ mwccarm_instruction_set_args = {
     'pxa261': ['-proc', 'pxa261'],
     'pxa262': ['-proc', 'pxa262'],
     'pxa263': ['-proc', 'pxa263']
-}  # type: T.Dict[str, T.List[str]]
+}
 
-mwcceppc_instruction_set_args = {
+mwcceppc_instruction_set_args: T.Dict[str, T.List[str]] = {
     'generic': ['-proc', 'generic'],
     '401': ['-proc', '401'],
     '403': ['-proc', '403'],
@@ -97,9 +97,9 @@ mwcceppc_instruction_set_args = {
     '8260': ['-proc', '8260'],
     'e500': ['-proc', 'e500'],
     'gekko': ['-proc', 'gekko'],
-}  # type: T.Dict[str, T.List[str]]
+}
 
-mwasmarm_instruction_set_args = {
+mwasmarm_instruction_set_args: T.Dict[str, T.List[str]] = {
     'arm4': ['-proc', 'arm4'],
     'arm4t': ['-proc', 'arm4t'],
     'arm4xm': ['-proc', 'arm4xm'],
@@ -112,9 +112,9 @@ mwasmarm_instruction_set_args = {
     'arm5TExP': ['-proc', 'arm5TExP'],
     'arm6': ['-proc', 'arm6'],
     'xscale': ['-proc', 'xscale']
-}  # type: T.Dict[str, T.List[str]]
+}
 
-mwasmeppc_instruction_set_args = {
+mwasmeppc_instruction_set_args: T.Dict[str, T.List[str]] = {
     '401': ['-proc', '401'],
     '403': ['-proc', '403'],
     '505': ['-proc', '505'],
@@ -165,9 +165,9 @@ mwasmeppc_instruction_set_args = {
     '5674': ['-proc', '5674'],
     'gekko': ['-proc', 'gekko'],
     'generic': ['-proc', 'generic'],
-}  # type: T.Dict[str, T.List[str]]
+}
 
-mwcc_optimization_args = {
+mwcc_optimization_args: T.Dict[str, T.List[str]] = {
     'plain': [],
     '0': ['-O0'],
     'g': ['-Op'],
@@ -175,12 +175,12 @@ mwcc_optimization_args = {
     '2': ['-O2'],
     '3': ['-O3'],
     's': ['-Os']
-}  # type: T.Dict[str, T.List[str]]
+}
 
-mwcc_debug_args = {
+mwcc_debug_args: T.Dict[bool, T.List[str]] = {
     False: [],
     True: ['-g']
-}  # type: T.Dict[bool, T.List[str]]
+}
 
 
 class MetrowerksCompiler(Compiler):
@@ -197,12 +197,13 @@ class MetrowerksCompiler(Compiler):
         self.base_options = {
             OptionKey(o) for o in ['b_pch', 'b_ndebug']}
 
-        default_warn_args = []  # type: T.List[str]
-        self.warn_args = {'0': ['-w', 'off'],
-                          '1': default_warn_args,
-                          '2': default_warn_args + ['-w', 'most'],
-                          '3': default_warn_args + ['-w', 'all'],
-                          'everything': default_warn_args + ['-w', 'full']}  # type: T.Dict[str, T.List[str]]
+        default_warn_args: T.List[str] = []
+        self.warn_args: T.Dict[str, T.List[str]] = {
+            '0': ['-w', 'off'],
+            '1': default_warn_args,
+            '2': default_warn_args + ['-w', 'most'],
+            '3': default_warn_args + ['-w', 'all'],
+            'everything': default_warn_args + ['-w', 'full']}
 
     def depfile_for_object(self, objfile: str) -> T.Optional[str]:
         # Earlier versions of these compilers do not support specifying
diff --git a/mesonbuild/compilers/mixins/ti.py b/mesonbuild/compilers/mixins/ti.py
index 950c97f..53688a9 100644
--- a/mesonbuild/compilers/mixins/ti.py
+++ b/mesonbuild/compilers/mixins/ti.py
@@ -31,16 +31,16 @@ else:
     # do). This gives up DRYer type checking, with no runtime impact
     Compiler = object
 
-ti_buildtype_args = {
+ti_buildtype_args: T.Dict[str, T.List[str]] = {
     'plain': [],
     'debug': [],
     'debugoptimized': [],
     'release': [],
     'minsize': [],
     'custom': [],
-}  # type: T.Dict[str, T.List[str]]
+}
 
-ti_optimization_args = {
+ti_optimization_args: T.Dict[str, T.List[str]] = {
     'plain': [],
     '0': ['-O0'],
     'g': ['-Ooff'],
@@ -48,12 +48,12 @@ ti_optimization_args = {
     '2': ['-O2'],
     '3': ['-O3'],
     's': ['-O4']
-}  # type: T.Dict[str, T.List[str]]
+}
 
-ti_debug_args = {
+ti_debug_args: T.Dict[bool, T.List[str]] = {
     False: [],
     True: ['-g']
-}  # type: T.Dict[bool, T.List[str]]
+}
 
 
 class TICompiler(Compiler):
@@ -67,12 +67,13 @@ class TICompiler(Compiler):
         self.can_compile_suffixes.add('asm')    # Assembly
         self.can_compile_suffixes.add('cla')    # Control Law Accelerator (CLA) used in C2000
 
-        default_warn_args = []  # type: T.List[str]
-        self.warn_args = {'0': [],
-                          '1': default_warn_args,
-                          '2': default_warn_args + [],
-                          '3': default_warn_args + [],
-                          'everything': default_warn_args + []}  # type: T.Dict[str, T.List[str]]
+        default_warn_args: T.List[str] = []
+        self.warn_args: T.Dict[str, T.List[str]] = {
+            '0': [],
+            '1': default_warn_args,
+            '2': default_warn_args + [],
+            '3': default_warn_args + [],
+            'everything': default_warn_args + []}
 
     def get_pic_args(self) -> T.List[str]:
         # PIC support is not enabled by default for TI compilers,
diff --git a/mesonbuild/compilers/mixins/visualstudio.py b/mesonbuild/compilers/mixins/visualstudio.py
index cc52538..cd71558 100644
--- a/mesonbuild/compilers/mixins/visualstudio.py
+++ b/mesonbuild/compilers/mixins/visualstudio.py
@@ -37,7 +37,7 @@ else:
     # do). This gives up DRYer type checking, with no runtime impact
     Compiler = object
 
-vs32_instruction_set_args = {
+vs32_instruction_set_args: T.Dict[str, T.Optional[T.List[str]]] = {
     'mmx': ['/arch:SSE'], # There does not seem to be a flag just for MMX
     'sse': ['/arch:SSE'],
     'sse2': ['/arch:SSE2'],
@@ -47,10 +47,10 @@ vs32_instruction_set_args = {
     'avx': ['/arch:AVX'],
     'avx2': ['/arch:AVX2'],
     'neon': None,
-}  # T.Dicst[str, T.Optional[T.List[str]]]
+}
 
 # The 64 bit compiler defaults to /arch:avx.
-vs64_instruction_set_args = {
+vs64_instruction_set_args: T.Dict[str, T.Optional[T.List[str]]] = {
     'mmx': ['/arch:AVX'],
     'sse': ['/arch:AVX'],
     'sse2': ['/arch:AVX'],
@@ -61,9 +61,9 @@ vs64_instruction_set_args = {
     'avx': ['/arch:AVX'],
     'avx2': ['/arch:AVX2'],
     'neon': None,
-}  # T.Dicst[str, T.Optional[T.List[str]]]
+}
 
-msvc_optimization_args = {
+msvc_optimization_args: T.Dict[str, T.List[str]] = {
     'plain': [],
     '0': ['/Od'],
     'g': [], # No specific flag to optimize debugging, /Zi or /ZI will create debug information
@@ -71,12 +71,12 @@ msvc_optimization_args = {
     '2': ['/O2'],
     '3': ['/O2', '/Gw'],
     's': ['/O1', '/Gw'],
-}  # type: T.Dict[str, T.List[str]]
+}
 
-msvc_debug_args = {
+msvc_debug_args: T.Dict[bool, T.List[str]] = {
     False: [],
     True: ['/Zi']
-}  # type: T.Dict[bool, T.List[str]]
+}
 
 
 class VisualStudioLikeCompiler(Compiler, metaclass=abc.ABCMeta):
@@ -92,15 +92,15 @@ class VisualStudioLikeCompiler(Compiler, metaclass=abc.ABCMeta):
     std_warn_args = ['/W3']
     std_opt_args = ['/O2']
     ignore_libs = arglist.UNIXY_COMPILER_INTERNAL_LIBS + ['execinfo']
-    internal_libs = []  # type: T.List[str]
+    internal_libs: T.List[str] = []
 
-    crt_args = {
+    crt_args: T.Dict[str, T.List[str]] = {
         'none': [],
         'md': ['/MD'],
         'mdd': ['/MDd'],
         'mt': ['/MT'],
         'mtd': ['/MTd'],
-    }  # type: T.Dict[str, T.List[str]]
+    }
 
     # /showIncludes is needed for build dependency tracking in Ninja
     # See: https://ninja-build.org/manual.html#_deps
@@ -109,13 +109,13 @@ class VisualStudioLikeCompiler(Compiler, metaclass=abc.ABCMeta):
     # It is also dropped if Visual Studio 2013 or earlier is used, since it would
     # not be supported in that case.
     always_args = ['/nologo', '/showIncludes', '/utf-8']
-    warn_args = {
+    warn_args: T.Dict[str, T.List[str]] = {
         '0': [],
         '1': ['/W2'],
         '2': ['/W3'],
         '3': ['/W4'],
         'everything': ['/Wall'],
-    }  # type: T.Dict[str, T.List[str]]
+    }
 
     INVOKES_LINKER = False