Use `env.machines.*` to avoid some `is_cross`

This is a small example of the `is_cross` removal the that abstraction
enables.

8 files changed, 75 insertions, 93 deletions

diff --git a/mesonbuild/backend/backends.py b/mesonbuild/backend/backends.py
index a044ab5..6e75974 100644
--- a/mesonbuild/backend/backends.py
+++ b/mesonbuild/backend/backends.py
@@ -743,8 +743,8 @@ class Backend:
                 exe_wrapper = self.environment.get_exe_wrapper()
             else:
                 exe_wrapper = None
-            if mesonlib.for_windows(is_cross, self.environment) or \
-               mesonlib.for_cygwin(is_cross, self.environment):
+            if mesonlib.for_windows(self.environment) or \
+               mesonlib.for_cygwin(self.environment):
                 extra_bdeps = []
                 if isinstance(exe, build.CustomTarget):
                     extra_bdeps = exe.get_transitive_build_target_deps()
diff --git a/mesonbuild/backend/ninjabackend.py b/mesonbuild/backend/ninjabackend.py
index 54fb117..c919d8f 100644
--- a/mesonbuild/backend/ninjabackend.py
+++ b/mesonbuild/backend/ninjabackend.py
@@ -665,8 +665,8 @@ int dummy;
         # CustomTarget command needs extra paths first.
         is_cross = self.environment.is_cross_build() and \
             self.environment.need_exe_wrapper()
-        if mesonlib.for_windows(is_cross, self.environment) or \
-           mesonlib.for_cygwin(is_cross, self.environment):
+        if mesonlib.for_windows(self.environment) or \
+           mesonlib.for_cygwin(self.environment):
             extra_bdeps = target.get_transitive_build_target_deps()
             extra_paths = self.determine_windows_extra_paths(target.command[0],
                                                              extra_bdeps, is_cross)
diff --git a/mesonbuild/build.py b/mesonbuild/build.py
index 65b2c20..3394459 100644
--- a/mesonbuild/build.py
+++ b/mesonbuild/build.py
@@ -928,7 +928,7 @@ This will become a hard error in a future Meson release.''')
             # You can't disable PIC on OS X. The compiler ignores -fno-PIC.
             # PIC is always on for Windows (all code is position-independent
             # since library loading is done differently)
-            if for_darwin(self.is_cross, self.environment) or for_windows(self.is_cross, self.environment):
+            if for_darwin(self.environment) or for_windows(self.environment):
                 self.pic = True
             else:
                 self.pic = self._extract_pic_pie(kwargs, 'pic')
@@ -1253,7 +1253,7 @@ You probably should put it in link_with instead.''')
         '''
         for link_target in self.link_targets:
             if isinstance(link_target, SharedModule):
-                if for_darwin(self.is_cross, self.environment):
+                if for_darwin(self.environment):
                     raise MesonException('''target links against shared modules.
 This is not permitted on OSX''')
                 else:
@@ -1436,8 +1436,8 @@ class Executable(BuildTarget):
             self.prefix = ''
         if not hasattr(self, 'suffix'):
             # Executable for Windows or C#/Mono
-            if (for_windows(is_cross, environment) or
-                    for_cygwin(is_cross, environment) or 'cs' in self.compilers):
+            if (for_windows(environment) or
+                    for_cygwin(environment) or 'cs' in self.compilers):
                 self.suffix = 'exe'
             elif ('c' in self.compilers and self.compilers['c'].get_id().startswith('arm') or
                   'cpp' in self.compilers and self.compilers['cpp'].get_id().startswith('arm')):
@@ -1475,7 +1475,7 @@ class Executable(BuildTarget):
             implib_basename = self.name + '.exe'
             if not isinstance(kwargs.get('implib', False), bool):
                 implib_basename = kwargs['implib']
-            if for_windows(is_cross, environment) or for_cygwin(is_cross, environment):
+            if for_windows(environment) or for_cygwin(environment):
                 self.vs_import_filename = '{0}.lib'.format(implib_basename)
                 self.gcc_import_filename = 'lib{0}.a'.format(implib_basename)
                 if self.get_using_msvc():
@@ -1652,7 +1652,7 @@ class SharedLibrary(BuildTarget):
         # C, C++, Swift, Vala
         # Only Windows uses a separate import library for linking
         # For all other targets/platforms import_filename stays None
-        elif for_windows(is_cross, env):
+        elif for_windows(env):
             suffix = 'dll'
             self.vs_import_filename = '{0}{1}.lib'.format(self.prefix if self.prefix is not None else '', self.name)
             self.gcc_import_filename = '{0}{1}.dll.a'.format(self.prefix if self.prefix is not None else 'lib', self.name)
@@ -1677,7 +1677,7 @@ class SharedLibrary(BuildTarget):
                 self.filename_tpl = '{0.prefix}{0.name}-{0.soversion}.{0.suffix}'
             else:
                 self.filename_tpl = '{0.prefix}{0.name}.{0.suffix}'
-        elif for_cygwin(is_cross, env):
+        elif for_cygwin(env):
             suffix = 'dll'
             self.gcc_import_filename = '{0}{1}.dll.a'.format(self.prefix if self.prefix is not None else 'lib', self.name)
             # Shared library is of the form cygfoo.dll
@@ -1689,7 +1689,7 @@ class SharedLibrary(BuildTarget):
                 self.filename_tpl = '{0.prefix}{0.name}-{0.soversion}.{0.suffix}'
             else:
                 self.filename_tpl = '{0.prefix}{0.name}.{0.suffix}'
-        elif for_darwin(is_cross, env):
+        elif for_darwin(env):
             prefix = 'lib'
             suffix = 'dylib'
             # On macOS, the filename can only contain the major version
@@ -1699,7 +1699,7 @@ class SharedLibrary(BuildTarget):
             else:
                 # libfoo.dylib
                 self.filename_tpl = '{0.prefix}{0.name}.{0.suffix}'
-        elif for_android(is_cross, env):
+        elif for_android(env):
             prefix = 'lib'
             suffix = 'so'
             # Android doesn't support shared_library versioning
@@ -1764,7 +1764,7 @@ class SharedLibrary(BuildTarget):
     def process_kwargs(self, kwargs, environment):
         super().process_kwargs(kwargs, environment)
 
-        if not for_android(self.is_cross, self.environment):
+        if not for_android(self.environment):
             supports_versioning = True
         else:
             supports_versioning = False
diff --git a/mesonbuild/compilers/clike.py b/mesonbuild/compilers/clike.py
index 3665f1f..968685b 100644
--- a/mesonbuild/compilers/clike.py
+++ b/mesonbuild/compilers/clike.py
@@ -274,9 +274,10 @@ class CLikeCompiler:
         return []
 
     def gen_export_dynamic_link_args(self, env):
-        if mesonlib.for_windows(env.is_cross_build(), env) or mesonlib.for_cygwin(env.is_cross_build(), env):
+        m = env.machines[self.for_machine]
+        if m.is_windows() or m.is_cygwin():
             return ['-Wl,--export-all-symbols']
-        elif mesonlib.for_darwin(env.is_cross_build(), env):
+        elif mesonlib.for_darwin(env):
             return []
         else:
             return ['-Wl,-export-dynamic']
@@ -884,7 +885,7 @@ class CLikeCompiler:
         for p in prefixes:
             for s in suffixes:
                 patterns.append(p + '{}.' + s)
-        if shared and mesonlib.for_openbsd(self.is_cross, env):
+        if shared and mesonlib.for_openbsd(env):
             # Shared libraries on OpenBSD can be named libfoo.so.X.Y:
             # https://www.openbsd.org/faq/ports/specialtopics.html#SharedLibs
             #
@@ -911,9 +912,9 @@ class CLikeCompiler:
         else:
             prefixes = ['lib', '']
         # Library suffixes and prefixes
-        if mesonlib.for_darwin(env.is_cross_build(), env):
+        if mesonlib.for_darwin(env):
             shlibext = ['dylib', 'so']
-        elif mesonlib.for_windows(env.is_cross_build(), env):
+        elif mesonlib.for_windows(env):
             # FIXME: .lib files can be import or static so we should read the
             # file, figure out which one it is, and reject the wrong kind.
             if isinstance(self, compilers.VisualStudioLikeCompiler):
@@ -922,7 +923,7 @@ class CLikeCompiler:
                 shlibext = ['dll.a', 'lib', 'dll']
             # Yep, static libraries can also be foo.lib
             stlibext += ['lib']
-        elif mesonlib.for_cygwin(env.is_cross_build(), env):
+        elif mesonlib.for_cygwin(env):
             shlibext = ['dll', 'dll.a']
             prefixes = ['cyg'] + prefixes
         else:
@@ -1126,12 +1127,12 @@ class CLikeCompiler:
         return self.find_framework_impl(name, env, extra_dirs, allow_system)
 
     def thread_flags(self, env):
-        if mesonlib.for_haiku(self.is_cross, env) or mesonlib.for_darwin(self.is_cross, env):
+        if mesonlib.for_haiku(env) or mesonlib.for_darwin(env):
             return []
         return ['-pthread']
 
     def thread_link_flags(self, env):
-        if mesonlib.for_haiku(self.is_cross, env) or mesonlib.for_darwin(self.is_cross, env):
+        if mesonlib.for_haiku(env) or mesonlib.for_darwin(env):
             return []
         return ['-pthread']
 
@@ -1189,8 +1190,8 @@ class CLikeCompiler:
     def has_func_attribute(self, name, env):
         # Just assume that if we're not on windows that dllimport and dllexport
         # don't work
-        if not (mesonlib.for_windows(env.is_cross_build(), env) or
-                mesonlib.for_cygwin(env.is_cross_build(), env)):
+        if not (mesonlib.for_windows(env) or
+                mesonlib.for_cygwin(env)):
             if name in ['dllimport', 'dllexport']:
                 return False, False
 
diff --git a/mesonbuild/dependencies/boost.py b/mesonbuild/dependencies/boost.py
index 0de1372..a955b6a 100644
--- a/mesonbuild/dependencies/boost.py
+++ b/mesonbuild/dependencies/boost.py
@@ -123,13 +123,13 @@ class BoostDependency(ExternalDependency):
             self.libdir = os.environ['BOOST_LIBRARYDIR']
 
         if self.boost_root is None:
-            if mesonlib.for_windows(self.want_cross, self.env):
+            if mesonlib.for_windows(self.env):
                 self.boost_roots = self.detect_win_roots()
             else:
                 self.boost_roots = self.detect_nix_roots()
 
         if self.incdir is None:
-            if mesonlib.for_windows(self.want_cross, self.env):
+            if mesonlib.for_windows(self.env):
                 self.incdir = self.detect_win_incdir()
             else:
                 self.incdir = self.detect_nix_incdir()
@@ -268,7 +268,7 @@ class BoostDependency(ExternalDependency):
             pass
         # 2. Fall back to the old method
         else:
-            if mesonlib.for_windows(self.want_cross, self.env):
+            if mesonlib.for_windows(self.env):
                 self.detect_lib_modules_win()
             else:
                 self.detect_lib_modules_nix()
@@ -290,7 +290,7 @@ class BoostDependency(ExternalDependency):
     def compiler_tag(self):
         tag = None
         compiler = self.env.detect_cpp_compiler(self.want_cross)
-        if mesonlib.for_windows(self.want_cross, self.env):
+        if mesonlib.for_windows(self.env):
             if compiler.get_id() in ['msvc', 'clang-cl']:
                 comp_ts_version = compiler.get_toolset_version()
                 compiler_ts = comp_ts_version.split('.')
@@ -304,10 +304,10 @@ class BoostDependency(ExternalDependency):
         if not self.is_multithreading:
             return ''
 
-        if mesonlib.for_darwin(self.want_cross, self.env):
+        if mesonlib.for_darwin(self.env):
             # - Mac:      requires -mt for multithreading, so should not fall back to non-mt libraries.
             return '-mt'
-        elif mesonlib.for_windows(self.want_cross, self.env):
+        elif mesonlib.for_windows(self.env):
             # - Windows:  requires -mt for multithreading, so should not fall back to non-mt libraries.
             return '-mt'
         else:
@@ -340,7 +340,7 @@ class BoostDependency(ExternalDependency):
 
     # FIXME - how to handle different distributions, e.g. for Mac? Currently we handle homebrew and macports, but not fink.
     def abi_tags(self):
-        if mesonlib.for_windows(self.want_cross, self.env):
+        if mesonlib.for_windows(self.env):
             return [self.versioned_abi_tag(), self.threading_tag()]
         else:
             return [self.threading_tag()]
@@ -437,7 +437,7 @@ class BoostDependency(ExternalDependency):
     def detect_lib_modules_nix(self):
         if self.static:
             libsuffix = 'a'
-        elif mesonlib.for_darwin(self.want_cross, self.env):
+        elif mesonlib.for_darwin(self.env):
             libsuffix = 'dylib'
         else:
             libsuffix = 'so'
diff --git a/mesonbuild/environment.py b/mesonbuild/environment.py
index ff4a6b1..f8603f6 100644
--- a/mesonbuild/environment.py
+++ b/mesonbuild/environment.py
@@ -513,12 +513,11 @@ class Environment:
         # Various prefixes and suffixes for import libraries, shared libraries,
         # static libraries, and executables.
         # Versioning is added to these names in the backends as-needed.
-        cross = self.is_cross_build()
-        if mesonlib.for_windows(cross, self):
+        if mesonlib.for_windows(self):
             self.exe_suffix = 'exe'
             self.object_suffix = 'obj'
             self.win_libdir_layout = True
-        elif mesonlib.for_cygwin(cross, self):
+        elif mesonlib.for_cygwin(self):
             self.exe_suffix = 'exe'
             self.object_suffix = 'o'
             self.win_libdir_layout = True
@@ -774,9 +773,9 @@ class Environment:
                 cls = ClangClCCompiler if lang == 'c' else ClangClCPPCompiler
                 return cls(compiler, version, is_cross, exe_wrap, target)
             if 'clang' in out:
-                if 'Apple' in out or mesonlib.for_darwin(want_cross, self):
+                if 'Apple' in out or mesonlib.for_darwin(self):
                     compiler_type = CompilerType.CLANG_OSX
-                elif 'windows' in out or mesonlib.for_windows(want_cross, self):
+                elif 'windows' in out or mesonlib.for_windows(self):
                     compiler_type = CompilerType.CLANG_MINGW
                 else:
                     compiler_type = CompilerType.CLANG_STANDARD
@@ -808,16 +807,16 @@ class Environment:
                 return cls(compiler, version, is_cross, exe_wrap, target)
 
             if 'PGI Compilers' in out:
-                if mesonlib.for_darwin(want_cross, self):
+                if self.machines[for_machine].is_darwin():
                     compiler_type = CompilerType.PGI_OSX
-                elif mesonlib.for_windows(want_cross, self):
+                elif self.machines[for_machine].is_windows():
                     compiler_type = CompilerType.PGI_WIN
                 else:
                     compiler_type = CompilerType.PGI_STANDARD
                 cls = PGICCompiler if lang == 'c' else PGICPPCompiler
                 return cls(ccache + compiler, version, compiler_type, is_cross, exe_wrap)
             if '(ICC)' in out:
-                if mesonlib.for_darwin(want_cross, self):
+                if self.machine[for_macine].is_darwin():
                     compiler_type = CompilerType.ICC_OSX
                 elif mesonlib.for_windows(want_cross, self):
                     # TODO: fix ICC on Windows
@@ -932,9 +931,9 @@ class Environment:
                     return PathScaleFortranCompiler(compiler, version, is_cross, exe_wrap, full_version=full_version)
 
                 if 'PGI Compilers' in out:
-                    if mesonlib.for_darwin(want_cross, self):
+                    if self.machine[for_macine].is_darwin():
                         compiler_type = CompilerType.PGI_OSX
-                    elif mesonlib.for_windows(want_cross, self):
+                    elif self.machines[for_machine].is_windows():
                         compiler_type = CompilerType.PGI_WIN
                     else:
                         compiler_type = CompilerType.PGI_STANDARD
diff --git a/mesonbuild/mesonlib.py b/mesonbuild/mesonlib.py
index e3ddf28..1b07d85 100644
--- a/mesonbuild/mesonlib.py
+++ b/mesonbuild/mesonlib.py
@@ -463,93 +463,75 @@ def is_dragonflybsd() -> bool:
 def is_freebsd() -> bool:
     return platform.system().lower() == 'freebsd'
 
-def _get_machine_is_cross(env, is_cross):
-    """
-    This is not morally correct, but works for now. For cross builds the build
-    and host machines differ. `is_cross == true` means the host machine, while
-    `is_cross == false` means the build machine. Both are used in practice,
-    even though the documentation refers to the host machine implying we should
-    hard-code it. For non-cross builds `is_cross == false` is passed but the
-    host and build machines are identical so it doesn't matter.
-
-    Users for `for_*` should instead specify up front which machine they want
-    and query that like:
-
-        env.machines[MachineChoice.HOST].is_haiku()
-
-    """
-    for_machine = MachineChoice.HOST if is_cross else MachineChoice.BUILD
-    return env.machines[for_machine]
-
-def for_windows(is_cross, env):
+def for_windows(env):
     """
     Host machine is windows?
 
-    Deprecated: Please use `env.machines[for_machine].is_windows()`.
+    Deprecated: Please use `env.machines.host.is_windows()`.
 
     Note: 'host' is the machine on which compiled binaries will run
     """
-    return _get_machine_is_cross(env, is_cross).is_windows()
+    return env.machines.host.is_windows()
 
-def for_cygwin(is_cross, env):
+def for_cygwin(env):
     """
     Host machine is cygwin?
 
-    Deprecated: Please use `env.machines[for_machine].is_cygwin()`.
+    Deprecated: Please use `env.machines.host.is_cygwin()`.
 
     Note: 'host' is the machine on which compiled binaries will run
     """
-    return _get_machine_is_cross(env, is_cross).is_cygwin()
+    return env.machines.host.is_cygwin()
 
-def for_linux(is_cross, env):
+def for_linux(env):
     """
     Host machine is linux?
 
-    Deprecated: Please use `env.machines[for_machine].is_linux()`.
+    Deprecated: Please use `env.machines.host.is_linux()`.
 
     Note: 'host' is the machine on which compiled binaries will run
     """
-    return _get_machine_is_cross(env, is_cross).is_linux()
+    return env.machines.host.is_linux()
 
-def for_darwin(is_cross, env):
+def for_darwin(env):
     """
     Host machine is Darwin (iOS/OS X)?
 
-    Deprecated: Please use `env.machines[for_machine].is_darwin()`.
+    Deprecated: Please use `env.machines.host.is_darwin()`.
 
     Note: 'host' is the machine on which compiled binaries will run
     """
-    return _get_machine_is_cross(env, is_cross).is_darwin()
+    return env.machines.host.is_darwin()
 
-def for_android(is_cross, env):
+def for_android(env):
     """
     Host machine is Android?
 
-    Deprecated: Please use `env.machines[for_machine].is_android()`.
+    Deprecated: Please use `env.machines.host.is_android()`.
 
     Note: 'host' is the machine on which compiled binaries will run
     """
-    return _get_machine_is_cross(env, is_cross).is_android()
+    return env.machines.host.is_android()
 
-def for_haiku(is_cross, env):
+def for_haiku(env):
     """
     Host machine is Haiku?
 
-    Deprecated: Please use `env.machines[for_machine].is_haiku()`.
+    Deprecated: Please use `env.machines.host.is_haiku()`.
 
     Note: 'host' is the machine on which compiled binaries will run
     """
-    return _get_machine_is_cross(env, is_cross).is_haiku()
+    return env.machines.host.is_haiku()
 
-def for_openbsd(is_cross, env):
+def for_openbsd(env):
     """
     Host machine is OpenBSD?
 
-    Deprecated: Please use `env.machines[for_machine].is_openbsd()`.
+    Deprecated: Please use `env.machines.host.is_openbsd()`.
 
     Note: 'host' is the machine on which compiled binaries will run
     """
-    return _get_machine_is_cross(env, is_cross).is_openbsd()
+    return env.machines.host.is_openbsd()
 
 def exe_exists(arglist: List[str]) -> bool:
     try:
diff --git a/run_project_tests.py b/run_project_tests.py
index f6d83b5..0f3e913 100755
--- a/run_project_tests.py
+++ b/run_project_tests.py
@@ -126,14 +126,14 @@ def platform_fix_name(fname, compiler, env):
         canonical_compiler = compiler
 
     if '?lib' in fname:
-        if mesonlib.for_windows(env.is_cross_build(), env) and canonical_compiler == 'msvc':
+        if env.machines.host.is_windows() and canonical_compiler == 'msvc':
             fname = re.sub(r'lib/\?lib(.*)\.', r'bin/\1.', fname)
             fname = re.sub(r'/\?lib/', r'/bin/', fname)
-        elif mesonlib.for_windows(env.is_cross_build(), env):
+        elif env.machines.host.is_windows():
             fname = re.sub(r'lib/\?lib(.*)\.', r'bin/lib\1.', fname)
             fname = re.sub(r'\?lib(.*)\.dll$', r'lib\1.dll', fname)
             fname = re.sub(r'/\?lib/', r'/bin/', fname)
-        elif mesonlib.for_cygwin(env.is_cross_build(), env):
+        elif env.machines.host.is_cygwin():
             fname = re.sub(r'lib/\?lib(.*)\.so$', r'bin/cyg\1.dll', fname)
             fname = re.sub(r'lib/\?lib(.*)\.', r'bin/cyg\1.', fname)
             fname = re.sub(r'\?lib(.*)\.dll$', r'cyg\1.dll', fname)
@@ -143,7 +143,7 @@ def platform_fix_name(fname, compiler, env):
 
     if fname.endswith('?exe'):
         fname = fname[:-4]
-        if mesonlib.for_windows(env.is_cross_build(), env) or mesonlib.for_cygwin(env.is_cross_build(), env):
+        if env.machines.host.is_windows() or env.machines.host.is_cygwin():
             return fname + '.exe'
 
     if fname.startswith('?msvc:'):
@@ -158,40 +158,40 @@ def platform_fix_name(fname, compiler, env):
 
     if fname.startswith('?cygwin:'):
         fname = fname[8:]
-        if not mesonlib.for_cygwin(env.is_cross_build(), env):
+        if not env.machines.host.is_cygwin():
             return None
 
     if fname.startswith('?!cygwin:'):
         fname = fname[9:]
-        if mesonlib.for_cygwin(env.is_cross_build(), env):
+        if env.machines.host.is_cygwin():
             return None
 
     if fname.endswith('?so'):
-        if mesonlib.for_windows(env.is_cross_build(), env) and canonical_compiler == 'msvc':
+        if env.machines.host.is_windows() and canonical_compiler == 'msvc':
             fname = re.sub(r'lib/([^/]*)\?so$', r'bin/\1.dll', fname)
             fname = re.sub(r'/(?:lib|)([^/]*?)\?so$', r'/\1.dll', fname)
             return fname
-        elif mesonlib.for_windows(env.is_cross_build(), env):
+        elif env.machines.host.is_windows():
             fname = re.sub(r'lib/([^/]*)\?so$', r'bin/\1.dll', fname)
             fname = re.sub(r'/([^/]*?)\?so$', r'/\1.dll', fname)
             return fname
-        elif mesonlib.for_cygwin(env.is_cross_build(), env):
+        elif env.machines.host.is_cygwin():
             fname = re.sub(r'lib/([^/]*)\?so$', r'bin/\1.dll', fname)
             fname = re.sub(r'/lib([^/]*?)\?so$', r'/cyg\1.dll', fname)
             fname = re.sub(r'/([^/]*?)\?so$', r'/\1.dll', fname)
             return fname
-        elif mesonlib.for_darwin(env.is_cross_build(), env):
+        elif env.machines.host.is_darwin():
             return fname[:-3] + '.dylib'
         else:
             return fname[:-3] + '.so'
 
     if fname.endswith('?implib') or fname.endswith('?implibempty'):
-        if mesonlib.for_windows(env.is_cross_build(), env) and canonical_compiler == 'msvc':
+        if env.machines.host.is_windows() and canonical_compiler == 'msvc':
             # only MSVC doesn't generate empty implibs
             if fname.endswith('?implibempty') and compiler == 'msvc':
                 return None
             return re.sub(r'/(?:lib|)([^/]*?)\?implib(?:empty|)$', r'/\1.lib', fname)
-        elif mesonlib.for_windows(env.is_cross_build(), env) or mesonlib.for_cygwin(env.is_cross_build(), env):
+        elif env.machines.host.is_windows() or env.machines.host.is_cygwin():
             return re.sub(r'\?implib(?:empty|)$', r'.dll.a', fname)
         else:
             return None