diff --git a/mesonbuild/compilers/asm.py b/mesonbuild/compilers/asm.py
index ab3a638f5..f25473b20 100644
--- a/mesonbuild/compilers/asm.py
+++ b/mesonbuild/compilers/asm.py
@@ -69,7 +69,7 @@ class NasmCompiler(Compiler):
         return ['-o', outputname]
 
     def unix_args_to_native(self, args: T.List[str]) -> T.List[str]:
-        outargs = []
+        outargs: T.List[str] = []
         for arg in args:
             if arg == '-pthread':
                 continue
diff --git a/mesonbuild/compilers/compilers.py b/mesonbuild/compilers/compilers.py
index 37893634b..56ed2d52b 100644
--- a/mesonbuild/compilers/compilers.py
+++ b/mesonbuild/compilers/compilers.py
@@ -537,7 +537,7 @@ class Compiler(HoldableObject, metaclass=abc.ABCMeta):
         if not hasattr(self, 'file_suffixes'):
             self.file_suffixes = lang_suffixes[self.language]
         if not hasattr(self, 'can_compile_suffixes'):
-            self.can_compile_suffixes = set(self.file_suffixes)
+            self.can_compile_suffixes: T.Set[str] = set(self.file_suffixes)
         self.default_suffix = self.file_suffixes[0]
         self.version = version
         self.full_version = full_version
diff --git a/mesonbuild/compilers/cpp.py b/mesonbuild/compilers/cpp.py
index f17b0d2f2..cd1ed9331 100644
--- a/mesonbuild/compilers/cpp.py
+++ b/mesonbuild/compilers/cpp.py
@@ -266,7 +266,7 @@ class ClangCPPCompiler(_StdCPPLibMixin, ClangCompiler, CPPCompiler):
         return opts
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         key = OptionKey('std', machine=self.for_machine, lang=self.language)
         std = options[key]
         if std.value != 'none':
@@ -318,7 +318,7 @@ class EmscriptenCPPCompiler(EmscriptenMixin, ClangCPPCompiler):
                                   defines=defines, full_version=full_version)
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         key = OptionKey('std', machine=self.for_machine, lang=self.language)
         std = options[key]
         if std.value != 'none':
@@ -362,7 +362,7 @@ class ArmclangCPPCompiler(ArmclangCompiler, CPPCompiler):
         return opts
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         key = OptionKey('std', machine=self.for_machine, lang=self.language)
         std = options[key]
         if std.value != 'none':
@@ -428,7 +428,7 @@ class GnuCPPCompiler(_StdCPPLibMixin, GnuCompiler, CPPCompiler):
         return opts
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         key = OptionKey('std', machine=self.for_machine, lang=self.language)
         std = options[key]
         if std.value != 'none':
@@ -539,7 +539,7 @@ class ElbrusCPPCompiler(ElbrusCompiler, CPPCompiler):
 
     # Elbrus C++ compiler does not support RTTI, so don't check for it.
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         key = OptionKey('std', machine=self.for_machine, lang=self.language)
         std = options[key]
         if std.value != 'none':
@@ -600,7 +600,7 @@ class IntelCPPCompiler(IntelGnuLikeCompiler, CPPCompiler):
         return opts
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         key = OptionKey('std', machine=self.for_machine, lang=self.language)
         std = options[key]
         if std.value != 'none':
@@ -667,7 +667,7 @@ class VisualStudioLikeCPPCompilerMixin(CompilerMixinBase):
         return opts
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         key = OptionKey('std', machine=self.for_machine, lang=self.language)
 
         eh = options[key.evolve('eh')]
@@ -832,7 +832,7 @@ class ArmCPPCompiler(ArmCompiler, CPPCompiler):
         return opts
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         key = OptionKey('std', machine=self.for_machine, lang=self.language)
         std = options[key]
         if std.value == 'c++11':
@@ -892,7 +892,7 @@ class TICPPCompiler(TICompiler, CPPCompiler):
         return opts
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         key = OptionKey('std', machine=self.for_machine, lang=self.language)
         std = options[key]
         if std.value != 'none':
@@ -931,7 +931,7 @@ class MetrowerksCPPCompilerARM(MetrowerksCompiler, CPPCompiler):
         return opts
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         std = options[OptionKey('std', machine=self.for_machine, lang=self.language)]
         if std.value != 'none':
             args.append('-lang')
@@ -960,7 +960,7 @@ class MetrowerksCPPCompilerEmbeddedPowerPC(MetrowerksCompiler, CPPCompiler):
         return opts
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         std = options[OptionKey('std', machine=self.for_machine, lang=self.language)]
         if std.value != 'none':
             args.append('-lang ' + std.value)
diff --git a/mesonbuild/compilers/d.py b/mesonbuild/compilers/d.py
index 358f8da94..08ebb7583 100644
--- a/mesonbuild/compilers/d.py
+++ b/mesonbuild/compilers/d.py
@@ -172,7 +172,7 @@ class DmdLikeCompilerMixin(CompilerMixinBase):
 
     def get_feature_args(self, kwargs: T.Dict[str, T.Any], build_to_src: str) -> T.List[str]:
         # TODO: using a TypeDict here would improve this
-        res = []
+        res: T.List[str] = []
         # get_feature_args can be called multiple times for the same target when there is generated source
         # so we have to copy the kwargs (target.d_features) dict before popping from it
         kwargs = kwargs.copy()
@@ -277,7 +277,7 @@ class DmdLikeCompilerMixin(CompilerMixinBase):
             # The way that dmd and ldc pass rpath to gcc is different than we would
             # do directly, each argument -rpath and the value to rpath, need to be
             # split into two separate arguments both prefaced with the -L=.
-            args = []
+            args: T.List[str] = []
             (rpath_args, rpath_dirs_to_remove) = super().build_rpath_args(
                     env, build_dir, from_dir, rpath_paths, build_rpath, install_rpath)
             for r in rpath_args:
@@ -298,7 +298,7 @@ class DmdLikeCompilerMixin(CompilerMixinBase):
         # can understand.
         # The flags might have been added by pkg-config files,
         # and are therefore out of the user's control.
-        dcargs = []
+        dcargs: T.List[str] = []
         # whether we hit a linker argument that expect another arg
         # see the comment in the "-L" section
         link_expect_arg = False
@@ -421,7 +421,7 @@ class DmdLikeCompilerMixin(CompilerMixinBase):
 
     @classmethod
     def translate_arg_to_windows(cls, arg: str) -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         if arg.startswith('-Wl,'):
             # Translate linker arguments here.
             linkargs = arg[arg.index(',') + 1:].split(',')
@@ -447,7 +447,7 @@ class DmdLikeCompilerMixin(CompilerMixinBase):
 
     @classmethod
     def _translate_arg_to_osx(cls, arg: str) -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         if arg.startswith('-install_name'):
             args.append('-L=' + arg)
         return args
@@ -500,15 +500,14 @@ class DmdLikeCompilerMixin(CompilerMixinBase):
 
         # LDC and DMD actually do use a linker, but they proxy all of that with
         # their own arguments
+        soargs: T.List[str] = []
         if self.linker.id.startswith('ld.'):
-            soargs = []
             for arg in sargs:
                 a, b = arg.split(',', maxsplit=1)
                 soargs.append(a)
                 soargs.append(self.LINKER_PREFIX + b)
             return soargs
         elif self.linker.id.startswith('ld64'):
-            soargs = []
             for arg in sargs:
                 if not arg.startswith(self.LINKER_PREFIX):
                     soargs.append(self.LINKER_PREFIX + arg)
@@ -589,7 +588,7 @@ class DCompiler(Compiler):
 
     def get_feature_args(self, kwargs: T.Dict[str, T.Any], build_to_src: str) -> T.List[str]:
         # TODO: using a TypeDict here would improve this
-        res = []
+        res: T.List[str] = []
         # get_feature_args can be called multiple times for the same target when there is generated source
         # so we have to copy the kwargs (target.d_features) dict before popping from it
         kwargs = kwargs.copy()
diff --git a/mesonbuild/compilers/fortran.py b/mesonbuild/compilers/fortran.py
index 06f8cb44c..a80fdff5f 100644
--- a/mesonbuild/compilers/fortran.py
+++ b/mesonbuild/compilers/fortran.py
@@ -170,7 +170,7 @@ class GnuFortranCompiler(GnuCompiler, FortranCompiler):
         return opts
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         key = OptionKey('std', machine=self.for_machine, lang=self.language)
         std = options[key]
         if std.value != 'none':
@@ -311,7 +311,7 @@ class IntelFortranCompiler(IntelGnuLikeCompiler, FortranCompiler):
         return opts
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         key = OptionKey('std', machine=self.for_machine, lang=self.language)
         std = options[key]
         stds = {'legacy': 'none', 'f95': 'f95', 'f2003': 'f03', 'f2008': 'f08', 'f2018': 'f18'}
@@ -364,7 +364,7 @@ class IntelClFortranCompiler(IntelVisualStudioLikeCompiler, FortranCompiler):
         return opts
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         key = OptionKey('std', machine=self.for_machine, lang=self.language)
         std = options[key]
         stds = {'legacy': 'none', 'f95': 'f95', 'f2003': 'f03', 'f2008': 'f08', 'f2018': 'f18'}
diff --git a/mesonbuild/compilers/mixins/ccrx.py b/mesonbuild/compilers/mixins/ccrx.py
index 6e503d15b..71c103338 100644
--- a/mesonbuild/compilers/mixins/ccrx.py
+++ b/mesonbuild/compilers/mixins/ccrx.py
@@ -110,7 +110,7 @@ class CcrxCompiler(Compiler):
 
     @classmethod
     def _unix_args_to_native(cls, args: T.List[str], info: MachineInfo) -> T.List[str]:
-        result = []
+        result: T.List[str] = []
         for i in args:
             if i.startswith('-D'):
                 i = '-define=' + i[2:]
diff --git a/mesonbuild/compilers/mixins/clike.py b/mesonbuild/compilers/mixins/clike.py
index d3e1008d1..978c05868 100644
--- a/mesonbuild/compilers/mixins/clike.py
+++ b/mesonbuild/compilers/mixins/clike.py
@@ -226,7 +226,7 @@ class CLikeCompiler(Compiler):
         # system directories aren't mixed, we only need to check one file for each
         # directory and go by that. If we can't check the file for some reason, assume
         # the compiler knows what it's doing, and accept the directory anyway.
-        retval = []
+        retval: T.List[str] = []
         for d in dirs:
             files = [f for f in os.listdir(d) if f.endswith('.so') and os.path.isfile(os.path.join(d, f))]
             # if no files, accept directory and move on
@@ -1216,7 +1216,7 @@ class CLikeCompiler(Compiler):
 
     def _find_framework_real(self, name: str, env: 'Environment', extra_dirs: T.List[str], allow_system: bool) -> T.Optional[T.List[str]]:
         code = 'int main(void) { return 0; }'
-        link_args = []
+        link_args: T.List[str] = []
         for d in extra_dirs:
             link_args += ['-F' + d]
         # We can pass -Z to disable searching in the system frameworks, but
diff --git a/mesonbuild/compilers/mixins/elbrus.py b/mesonbuild/compilers/mixins/elbrus.py
index 872649bb5..ad6b7ca05 100644
--- a/mesonbuild/compilers/mixins/elbrus.py
+++ b/mesonbuild/compilers/mixins/elbrus.py
@@ -74,7 +74,7 @@ class ElbrusCompiler(GnuLikeCompiler):
         os_env['LC_ALL'] = 'C'
         p = subprocess.Popen(self.get_exelist(ccache=False) + ['-xc', '-E', '-v', '-'], env=os_env, stdin=subprocess.DEVNULL, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
         stderr = p.stderr.read().decode('utf-8', errors='replace')
-        includes = []
+        includes: T.List[str] = []
         for line in stderr.split('\n'):
             if line.lstrip().startswith('--sys_include'):
                 includes.append(re.sub(r'\s*\\$', '', re.sub(r'^\s*--sys_include\s*', '', line)))
@@ -91,7 +91,7 @@ class ElbrusCompiler(GnuLikeCompiler):
         return 'pch'
 
     def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
-        args = []
+        args: T.List[str] = []
         std = options[OptionKey('std', lang=self.language, machine=self.for_machine)]
         if std.value != 'none':
             args.append('-std=' + std.value)
diff --git a/mesonbuild/compilers/mixins/emscripten.py b/mesonbuild/compilers/mixins/emscripten.py
index f95e63ff9..a07cff3cd 100644
--- a/mesonbuild/compilers/mixins/emscripten.py
+++ b/mesonbuild/compilers/mixins/emscripten.py
@@ -37,7 +37,7 @@ else:
 
 
 def wrap_js_includes(args: T.List[str]) -> T.List[str]:
-    final_args = []
+    final_args: T.List[str] = []
     for i in args:
         if i.endswith('.js') and not i.startswith('-'):
             final_args += ['--js-library', i]
diff --git a/mesonbuild/compilers/mixins/gnu.py b/mesonbuild/compilers/mixins/gnu.py
index 703fb1ae8..7b7bc890b 100644
--- a/mesonbuild/compilers/mixins/gnu.py
+++ b/mesonbuild/compilers/mixins/gnu.py
@@ -483,7 +483,7 @@ class GnuLikeCompiler(Compiler, metaclass=abc.ABCMeta):
         # pathlib treats empty paths as '.', so filter those out
         paths = [p for p in pathstr.split(pathsep) if p]
 
-        result = []
+        result: T.List[str] = []
         for p in paths:
             # GCC returns paths like this:
             # /usr/lib/gcc/x86_64-linux-gnu/8/../../../../x86_64-linux-gnu/lib
@@ -590,7 +590,7 @@ class GnuCompiler(GnuLikeCompiler):
         return args
 
     def supported_warn_args(self, warn_args_by_version: T.Dict[str, T.List[str]]) -> T.List[str]:
-        result = []
+        result: T.List[str] = []
         for version, warn_args in warn_args_by_version.items():
             if mesonlib.version_compare(self.version, '>=' + version):
                 result += warn_args
diff --git a/mesonbuild/compilers/mixins/metrowerks.py b/mesonbuild/compilers/mixins/metrowerks.py
index 970faeb99..7aab9b52e 100644
--- a/mesonbuild/compilers/mixins/metrowerks.py
+++ b/mesonbuild/compilers/mixins/metrowerks.py
@@ -278,7 +278,7 @@ class MetrowerksCompiler(Compiler):
 
     @classmethod
     def _unix_args_to_native(cls, args: T.List[str], info: MachineInfo) -> T.List[str]:
-        result = []
+        result: T.List[str] = []
         for i in args:
             if i.startswith('-D'):
                 i = '-D' + i[2:]
diff --git a/mesonbuild/compilers/mixins/ti.py b/mesonbuild/compilers/mixins/ti.py
index 53688a9df..6123aea88 100644
--- a/mesonbuild/compilers/mixins/ti.py
+++ b/mesonbuild/compilers/mixins/ti.py
@@ -126,7 +126,7 @@ class TICompiler(Compiler):
 
     @classmethod
     def _unix_args_to_native(cls, args: T.List[str], info: MachineInfo) -> T.List[str]:
-        result = []
+        result: T.List[str] = []
         for i in args:
             if i.startswith('-D'):
                 i = '--define=' + i[2:]
diff --git a/mesonbuild/compilers/mixins/visualstudio.py b/mesonbuild/compilers/mixins/visualstudio.py
index cd715589c..54a95bb0f 100644
--- a/mesonbuild/compilers/mixins/visualstudio.py
+++ b/mesonbuild/compilers/mixins/visualstudio.py
@@ -277,7 +277,7 @@ class VisualStudioLikeCompiler(Compiler, metaclass=abc.ABCMeta):
 
     @classmethod
     def native_args_to_unix(cls, args: T.List[str]) -> T.List[str]:
-        result = []
+        result: T.List[str] = []
         for arg in args:
             if arg.startswith(('/LIBPATH:', '-LIBPATH:')):
                 result.append('-L' + arg[9:])
@@ -491,7 +491,7 @@ class ClangClCompiler(VisualStudioLikeCompiler):
 
     def get_dependency_compile_args(self, dep: 'Dependency') -> T.List[str]:
         if dep.get_include_type() == 'system':
-            converted = []
+            converted: T.List[str] = []
             for i in dep.get_compile_args():
                 if i.startswith('-isystem'):
                     converted += ['/clang:' + i]
diff --git a/mesonbuild/coredata.py b/mesonbuild/coredata.py
index b6dfdbf7e..72f104248 100644
--- a/mesonbuild/coredata.py
+++ b/mesonbuild/coredata.py
@@ -164,7 +164,7 @@ class UserIntegerOption(UserOption[int]):
         min_value, max_value, default_value = value
         self.min_value = min_value
         self.max_value = max_value
-        c = []
+        c: T.List[str] = []
         if min_value is not None:
             c.append('>=' + str(min_value))
         if max_value is not None:
@@ -419,7 +419,7 @@ class DependencyCache:
 
     def items(self) -> T.Iterator[T.Tuple['TV_DepID', T.List['dependencies.Dependency']]]:
         for k, v in self.__cache.items():
-            vs = []
+            vs: T.List[dependencies.Dependency] = []
             for t in v.types:
                 subkey = self.__calculate_subkey(t)
                 if subkey in v:
@@ -731,7 +731,7 @@ class CoreData:
         self.run_check_cache.clear()
 
     def get_nondefault_buildtype_args(self) -> T.List[T.Union[T.Tuple[str, str, str], T.Tuple[str, bool, bool]]]:
-        result = []
+        result: T.List[T.Union[T.Tuple[str, str, str], T.Tuple[str, bool, bool]]] = []
         value = self.options[OptionKey('buildtype')].value
         if value == 'plain':
             opt = 'plain'
diff --git a/mesonbuild/environment.py b/mesonbuild/environment.py
index c5cccf3f8..4e943ba4c 100644
--- a/mesonbuild/environment.py
+++ b/mesonbuild/environment.py
@@ -178,7 +178,7 @@ def get_llvm_tool_names(tool: str) -> T.List[str]:
         '-15',    # Debian development snapshot
         '-devel', # FreeBSD development snapshot
     ]
-    names = []
+    names: T.List[str] = []
     for suffix in suffixes:
         names.append(tool + suffix)
     return names
@@ -197,15 +197,16 @@ def detect_scanbuild() -> T.List[str]:
     Return: a single-element list of the found scan-build binary ready to be
         passed to Popen()
     """
-    exelist = []
+    exelist: T.List[str] = []
     if 'SCANBUILD' in os.environ:
         exelist = split_args(os.environ['SCANBUILD'])
 
     else:
         tools = get_llvm_tool_names('scan-build')
         for tool in tools:
-            if shutil.which(tool) is not None:
-                exelist = [shutil.which(tool)]
+            which = shutil.which(tool)
+            if which is not None:
+                exelist = [which]
                 break
 
     if exelist:
diff --git a/mesonbuild/linkers/linkers.py b/mesonbuild/linkers/linkers.py
index 4b52c26b1..8675766b8 100644
--- a/mesonbuild/linkers/linkers.py
+++ b/mesonbuild/linkers/linkers.py
@@ -374,7 +374,7 @@ class DynamicLinker(metaclass=abc.ABCMeta):
             return args
         elif isinstance(self.prefix_arg, str):
             return [self.prefix_arg + arg for arg in args]
-        ret = []
+        ret: T.List[str] = []
         for arg in args:
             ret += self.prefix_arg + [arg]
         return ret
@@ -670,14 +670,14 @@ class GnuLikeDynamicLinkerMixin:
             return ([], set())
         if not rpath_paths and not install_rpath and not build_rpath:
             return ([], set())
-        args = []
+        args: T.List[str] = []
         origin_placeholder = '$ORIGIN'
         processed_rpaths = prepare_rpaths(rpath_paths, build_dir, from_dir)
         # Need to deduplicate rpaths, as macOS's install_name_tool
         # is *very* allergic to duplicate -delete_rpath arguments
         # when calling depfixer on installation.
         all_paths = mesonlib.OrderedSet([os.path.join(origin_placeholder, p) for p in processed_rpaths])
-        rpath_dirs_to_remove = set()
+        rpath_dirs_to_remove: T.Set[bytes] = set()
         for p in all_paths:
             rpath_dirs_to_remove.add(p.encode('utf8'))
         # Build_rpath is used as-is (it is usually absolute).
@@ -812,7 +812,7 @@ class AppleDynamicLinker(PosixDynamicLinkerMixin, DynamicLinker):
                          install_rpath: str) -> T.Tuple[T.List[str], T.Set[bytes]]:
         if not rpath_paths and not install_rpath and not build_rpath:
             return ([], set())
-        args = []
+        args: T.List[str] = []
         # @loader_path is the equivalent of $ORIGIN on macOS
         # https://stackoverflow.com/q/26280738
         origin_placeholder = '@loader_path'
@@ -1152,7 +1152,7 @@ class NAGDynamicLinker(PosixDynamicLinkerMixin, DynamicLinker):
                          install_rpath: str) -> T.Tuple[T.List[str], T.Set[bytes]]:
         if not rpath_paths and not install_rpath and not build_rpath:
             return ([], set())
-        args = []
+        args: T.List[str] = []
         origin_placeholder = '$ORIGIN'
         processed_rpaths = prepare_rpaths(rpath_paths, build_dir, from_dir)
         all_paths = mesonlib.OrderedSet([os.path.join(origin_placeholder, p) for p in processed_rpaths])
@@ -1409,7 +1409,7 @@ class SolarisDynamicLinker(PosixDynamicLinkerMixin, DynamicLinker):
             return ([], set())
         processed_rpaths = prepare_rpaths(rpath_paths, build_dir, from_dir)
         all_paths = mesonlib.OrderedSet([os.path.join('$ORIGIN', p) for p in processed_rpaths])
-        rpath_dirs_to_remove = set()
+        rpath_dirs_to_remove: T.Set[bytes] = set()
         for p in all_paths:
             rpath_dirs_to_remove.add(p.encode('utf8'))
         if build_rpath != '':
diff --git a/mesonbuild/utils/universal.py b/mesonbuild/utils/universal.py
index c6a4e41c7..35da2f40c 100644
--- a/mesonbuild/utils/universal.py
+++ b/mesonbuild/utils/universal.py
@@ -913,8 +913,8 @@ def version_compare(vstr1: str, vstr2: str) -> bool:
 def version_compare_many(vstr1: str, conditions: T.Union[str, T.Iterable[str]]) -> T.Tuple[bool, T.List[str], T.List[str]]:
     if isinstance(conditions, str):
         conditions = [conditions]
-    found = []
-    not_found = []
+    found: T.List[str] = []
+    not_found: T.List[str] = []
     for req in conditions:
         if not version_compare(vstr1, req):
             not_found.append(req)
@@ -1123,7 +1123,7 @@ if is_windows():
         return result
 
     def split_args(cmd: str) -> T.List[str]:
-        result = []
+        result: T.List[str] = []
         arg = ''
         num_backslashes = 0
         num_quotes = 0
@@ -1210,7 +1210,7 @@ def do_define(regex: T.Pattern[str], line: str, confdata: 'ConfigurationData',
               variable_format: Literal['meson', 'cmake', 'cmake@'], subproject: T.Optional[SubProject] = None) -> str:
     def get_cmake_define(line: str, confdata: 'ConfigurationData') -> str:
         arr = line.split()
-        define_value = []
+        define_value: T.List[str] = []
         for token in arr[2:]:
             try:
                 (v, desc) = confdata.get(token)
@@ -1277,8 +1277,8 @@ def do_conf_str(src: str, data: list, confdata: 'ConfigurationData',
     if variable_format != 'meson':
         search_token = '#cmakedefine'
 
-    result = []
-    missing_variables = set()
+    result: T.List[str] = []
+    missing_variables: T.Set[str] = set()
     # Detect when the configuration data is empty and no tokens were found
     # during substitution so we can warn the user to use the `copy:` kwarg.
     confdata_useless = not confdata.keys()
@@ -2017,9 +2017,9 @@ def get_wine_shortpath(winecmd: T.List[str], wine_paths: T.List[str],
         return wine_path
 
     # Check paths that can be reduced by making them relative to workdir.
-    rel_paths = []
+    rel_paths: T.List[str] = []
     if workdir:
-        abs_paths = []
+        abs_paths: T.List[str] = []
         for p in wine_paths:
             try:
                 rel = Path(p).relative_to(workdir)