Make sure machine_info_can_run() isn't called on incomplete MachineInfo

If need_exe_wrapper() is called while figuring out the language compiler,
the MachineInfo isn't complete yet, so machine_info_can_run() would return
False despite not cross compiling.

Make sure this fails loudly.

Squash of the following cherry-picked commits:
- mesonbuild@df833b0
- mesonbuild@c108d5b
- mesonbuild@eba9e7e

mesonbuild/backend/backends.py

@@ -568,7 +568,8 @@ def get_executable_serialisation(
         else:
             extra_paths = []
 
-        if self.environment.need_exe_wrapper(exe_for_machine):
+        is_cross_built = not self.environment.machines.matches_build_machine(exe_for_machine)
+        if is_cross_built and self.environment.need_exe_wrapper():
             if not self.environment.has_exe_wrapper():
                 msg = 'An exe_wrapper is needed but was not found. Please define one ' \
                       'in cross file and check the command and/or add it to PATH.'

mesonbuild/compilers/cuda.py

@@ -551,7 +551,7 @@ def sanity_check(self, work_dir: str, env: 'Environment') -> None:
         flags += self.get_ccbin_args(env.coredata.options)
 
         # If cross-compiling, we can't run the sanity check, only compile it.
-        if env.need_exe_wrapper(self.for_machine) and not env.has_exe_wrapper():
+        if self.is_cross and not env.has_exe_wrapper():
             # Linking cross built apps is painful. You can't really
             # tell if you should use -nostdlib or not and for example
             # on OSX the compiler binary is the same but you need
@@ -573,7 +573,7 @@ def sanity_check(self, work_dir: str, env: 'Environment') -> None:
             raise EnvironmentException(f'Compiler {self.name_string()} cannot compile programs.')
 
         # Run sanity check (if possible)
-        if env.need_exe_wrapper(self.for_machine):
+        if self.is_cross:
             if not env.has_exe_wrapper():
                 return
             else:

mesonbuild/compilers/d.py

@@ -447,15 +447,15 @@ def sanity_check(self, work_dir: str, environment: 'Environment') -> None:
         compile_cmdlist = self.exelist + self.get_output_args(output_name) + self._get_target_arch_args() + [source_name]
 
         # If cross-compiling, we can't run the sanity check, only compile it.
-        if environment.need_exe_wrapper(self.for_machine) and not environment.has_exe_wrapper():
+        if self.is_cross and not environment.has_exe_wrapper():
             compile_cmdlist += self.get_compile_only_args()
 
         pc = subprocess.Popen(compile_cmdlist, cwd=work_dir)
         pc.wait()
         if pc.returncode != 0:
             raise EnvironmentException('D compiler %s cannot compile programs.' % self.name_string())
 
-        if environment.need_exe_wrapper(self.for_machine):
+        if self.is_cross:
             if not environment.has_exe_wrapper():
                 # Can't check if the binaries run so we have to assume they do
                 return

mesonbuild/compilers/mixins/clike.py

@@ -278,7 +278,7 @@ def _sanity_check_impl(self, work_dir: str, environment: 'Environment',
         mode = CompileCheckMode.LINK
         if self.is_cross:
             binname += '_cross'
-            if environment.need_exe_wrapper(self.for_machine) and not environment.has_exe_wrapper():
+            if not environment.has_exe_wrapper():
                 # Linking cross built C/C++ apps is painful. You can't really
                 # tell if you should use -nostdlib or not and for example
                 # on OSX the compiler binary is the same but you need
@@ -308,7 +308,7 @@ def _sanity_check_impl(self, work_dir: str, environment: 'Environment',
         if pc.returncode != 0:
             raise mesonlib.EnvironmentException(f'Compiler {self.name_string()} cannot compile programs.')
         # Run sanity check
-        if environment.need_exe_wrapper(self.for_machine):
+        if self.is_cross:
             if not environment.has_exe_wrapper():
                 # Can't check if the binaries run so we have to assume they do
                 return

mesonbuild/compilers/rust.py

@@ -86,7 +86,7 @@ def sanity_check(self, work_dir: str, environment: 'Environment') -> None:
         if pc.returncode != 0:
             raise EnvironmentException(f'Rust compiler {self.name_string()} cannot compile programs.')
         self._native_static_libs(work_dir, source_name)
-        if environment.need_exe_wrapper(self.for_machine):
+        if self.is_cross:
             if not environment.has_exe_wrapper():
                 # Can't check if the binaries run so we have to assume they do
                 return

mesonbuild/environment.py

@@ -505,6 +505,7 @@ def machine_info_can_run(machine_info: MachineInfo):
     if machine_info.system != detect_system():
         return False
     true_build_cpu_family = detect_cpu_family({})
+    assert machine_info.cpu_family is not None, 'called on incomplete machine_info'
     return \
         (machine_info.cpu_family == true_build_cpu_family) or \
         ((true_build_cpu_family == 'x86_64') and (machine_info.cpu_family == 'x86')) or \