compilers: Convert b_sanitize to a freeform array option

There are a lot of sanitizers these days, and trying to keep up with
them would be entirely too much work. Instead we'll do a compile check
to see if the option is valid. An array makes more sense than a string,
since users could just write `address,undefined` or they could write
`undefined,address`. With the array we get to handle that ourselves and
users writing code know that it's not safe to simply do a check like
```meson
if get_option('b_sanitize') == 'address,undefined'
  ...
endif
```

instead they need to do something like
```meson
opt = get_option('b_sanitize')
if opt.contains('address') and opt.contains('undefined')
   ...
endif
```

To ensure backwards compatibility, a special check has been added to the
get_option() call for `b_sanitize`, which converts it to a string if the
compatibility is < 0.63, with a warning that the behavior will change in
the future.

Fixes mesonbuild#8283
Fixes mesonbuild#7761
Fixes mesonbuild#5154
Fixes mesonbuild#1582

docs/markdown/snippets/b_sanitizer_changes.md

@@ -0,0 +1,17 @@
+## Changes to the b_sanitize option
+
+In meson <= 0.62 the b_sanitize option is a combo, which is an enumerated set of
+values. One picks one of the values as provided by that enumeration. In 0.63
+this was changed to a free array of options, and a compiler check for the
+validity of those options.
+
+This solves a number of longstanding issues such as:
+ - sanitizers may be supported by a compiler, but not on a specific platform (OpenBSD)
+ - new sanitizers are not recognized by Meson
+ - using sanitizers in different combinations
+
+In order to not break backwards compatibility, meson will make continue to
+return `get_option('b_sanitize')` as a string if the requested meson version is
+`< 0.63`. In addition, it alphabetically sorts the values so that
+`undefined,address` will still be presented as `address,undefined`. When the
+minimum version is changed to >= 0.63, then it will return an array of strings.

mesonbuild/backend/vs2010backend.py

@@ -217,7 +217,7 @@ def generate(self):
         try:
             self.sanitize = self.environment.coredata.get_option(OptionKey('b_sanitize'))
         except MesonException:
-            self.sanitize = 'none'
+            self.sanitize = []
         sln_filename = os.path.join(self.environment.get_build_dir(), self.build.project_name + '.sln')
         projlist = self.generate_projects()
         self.gen_testproj('RUN_TESTS', os.path.join(self.environment.get_build_dir(), 'RUN_TESTS.vcxproj'))

mesonbuild/compilers/compilers.py

@@ -277,9 +277,7 @@ class CompileCheckMode(enum.Enum):
     OptionKey('b_lto_mode'): coredata.UserComboOption('Select between different LTO modes.',
                                                       ['default', 'thin'],
                                                       'default'),
-    OptionKey('b_sanitize'): coredata.UserComboOption('Code sanitizer to use',
-                                                      ['none', 'address', 'thread', 'undefined', 'memory', 'leak', 'address,undefined'],
-                                                      'none'),
+    OptionKey('b_sanitize'): coredata.UserArrayOption('Code sanitizer to use', []),
     OptionKey('b_lundef'): coredata.UserBooleanOption('Use -Wl,--no-undefined when linking', True),
     OptionKey('b_asneeded'): coredata.UserBooleanOption('Use -Wl,--as-needed when linking', True),
     OptionKey('b_pgo'): coredata.UserComboOption('Use profile guided optimization',
@@ -391,7 +389,8 @@ def get_base_link_args(options: 'KeyedOptionDictType', linker: 'Compiler',
     except KeyError:
         pass
     try:
-        sani_opt = options[OptionKey('b_sanitize')].value
+        sani_opt: T.List[str] = options[OptionKey('b_sanitize')].value
+        assert isinstance(sani_opt, list), 'for mypy'
         sani_args = linker.sanitizer_link_args(sani_opt)
         # We consider that if there are no sanitizer arguments returned, then the language doesn't support them
         if sani_args:
@@ -994,10 +993,10 @@ def get_lto_compile_args(self, *, threads: int = 0, mode: str = 'default') -> T.
     def get_lto_link_args(self, *, threads: int = 0, mode: str = 'default') -> T.List[str]:
         return self.linker.get_lto_args()
 
-    def sanitizer_compile_args(self, value: str) -> T.List[str]:
+    def sanitizer_compile_args(self, value: T.List[str]) -> T.List[str]:
         return []
 
-    def sanitizer_link_args(self, value: str) -> T.List[str]:
+    def sanitizer_link_args(self, value: T.List[str]) -> T.List[str]:
         return self.linker.sanitizer_args(value)
 
     def get_asneeded_args(self) -> T.List[str]:

mesonbuild/compilers/cuda.py

@@ -671,10 +671,10 @@ def get_optimization_args(self, optimization_level: str) -> T.List[str]:
         # return self._to_host_flags(self.host_compiler.get_optimization_args(optimization_level))
         return cuda_optimization_args[optimization_level]
 
-    def sanitizer_compile_args(self, value: str) -> T.List[str]:
+    def sanitizer_compile_args(self, value: T.List[str]) -> T.List[str]:
         return self._to_host_flags(self.host_compiler.sanitizer_compile_args(value))
 
-    def sanitizer_link_args(self, value: str) -> T.List[str]:
+    def sanitizer_link_args(self, value: T.List[str]) -> T.List[str]:
         return self._to_host_flags(self.host_compiler.sanitizer_link_args(value))
 
     def get_debug_args(self, is_debug: bool) -> T.List[str]:

mesonbuild/compilers/mixins/gnu.py

@@ -283,11 +283,11 @@ def get_lto_compile_args(self, *, threads: int = 0, mode: str = 'default') -> T.
         # for their specific arguments
         return ['-flto']
 
-    def sanitizer_compile_args(self, value: str) -> T.List[str]:
-        if value == 'none':
-            return []
-        args = ['-fsanitize=' + value]
-        if 'address' in value:  # for -fsanitize=address,undefined
+    def sanitizer_compile_args(self, value: T.List[str]) -> T.List[str]:
+        if not value:
+            return value
+        args = ['-fsanitize=' + ','.join(value)]
+        if 'address' in value:
             args.append('-fno-omit-frame-pointer')
         return args
 

mesonbuild/compilers/mixins/islinker.py

@@ -45,7 +45,7 @@ class BasicLinkerIsCompilerMixin(Compiler):
     functionality itself.
     """
 
-    def sanitizer_link_args(self, value: str) -> T.List[str]:
+    def sanitizer_link_args(self, value: T.List[str]) -> T.List[str]:
         return []
 
     def get_lto_link_args(self, *, threads: int = 0, mode: str = 'default') -> T.List[str]:

mesonbuild/compilers/mixins/visualstudio.py

@@ -168,12 +168,10 @@ def get_compile_only_args(self) -> T.List[str]:
     def get_no_optimization_args(self) -> T.List[str]:
         return ['/Od', '/Oi-']
 
-    def sanitizer_compile_args(self, value: str) -> T.List[str]:
-        if value == 'none':
-            return []
-        if value != 'address':
-            raise mesonlib.MesonException('VS only supports address sanitizer at the moment.')
-        return ['/fsanitize=address']
+    def sanitizer_compile_args(self, value: T.List[str]) -> T.List[str]:
+        if not value:
+            return value
+        return [f'/fsanitize={",".join(value)}']
 
     def get_output_args(self, target: str) -> T.List[str]:
         if target.endswith('.exe'):

mesonbuild/interpreter/interpreter.py

@@ -1060,7 +1060,7 @@ def get_option_internal(self, optname: str) -> coredata.UserOption:
 
     @typed_pos_args('get_option', str)
     @noKwargs
-    def func_get_option(self, nodes: mparser.BaseNode, args: T.Tuple[str],
+    def func_get_option(self, node: mparser.BaseNode, args: T.Tuple[str],
                         kwargs: 'TYPE_kwargs') -> T.Union[coredata.UserOption, 'TYPE_var']:
         optname = args[0]
         if ':' in optname:
@@ -1071,6 +1071,26 @@ def func_get_option(self, nodes: mparser.BaseNode, args: T.Tuple[str],
         if isinstance(opt, coredata.UserFeatureOption):
             opt.name = optname
             return opt
+        elif optname == 'b_sanitize':
+            assert isinstance(opt, coredata.UserArrayOption), 'for mypy'
+            # Handle the change of sanitize from a combo to an array
+            # if the version compat is < 0.63 then we return a `,` joined
+            # string, sorted alphabetically (so that address,undefined remains
+            # unchanged), otherwise we return an array
+
+            # TODO: this should be 0.63, but there's no way to test this until 0.63 if it is
+            if mesonlib.version_compare(mesonlib.project_meson_versions[self.subproject], '< 0.62.99'):
+                # Use deprecation to not trip up --fatal-warnings
+                mlog.deprecation(textwrap.dedent('''\
+                    In meson 0.63 the type of the builtin "b_sanitize" option changed from a combo to an array of strings. For
+                    compatiblity, projects that set their minimum version < 0.63 will continue to get a string from the command
+                    `get_option('b_sanitize')`, even when using meson > 0.63.  When the minimum version changes this will change to an
+                    array. Meson will attempt to provide the same values as before, (such as sorting to try to match `address,undefined`),
+                    however, new values available in meson >= 0.63 may trip this up, and any reliance on this should be removed,
+                    as the array version will be provided in user provided order.
+                    '''), location=node)
+                return ','.join(sorted(opt.value))
+            return opt.value
         elif isinstance(opt, coredata.UserOption):
             return opt.value
         return opt
@@ -2816,7 +2836,7 @@ def check_clang_asan_lundef(self) -> None:
         if OptionKey('b_sanitize') not in self.coredata.options:
             return
         if (self.coredata.options[OptionKey('b_lundef')].value and
-                self.coredata.options[OptionKey('b_sanitize')].value != 'none'):
+                self.coredata.options[OptionKey('b_sanitize')].value):
             mlog.warning('''Trying to use {} sanitizer on Clang with b_lundef.
 This will probably not work.
 Try setting b_lundef to false instead.'''.format(self.coredata.options[OptionKey('b_sanitize')].value),

mesonbuild/linkers/linkers.py

@@ -448,7 +448,7 @@ def get_pie_args(self) -> T.List[str]:
     def get_lto_args(self) -> T.List[str]:
         return []
 
-    def sanitizer_args(self, value: str) -> T.List[str]:
+    def sanitizer_args(self, value: T.List[str]) -> T.List[str]:
         return []
 
     def get_buildtype_args(self, buildtype: str) -> T.List[str]:
@@ -594,10 +594,10 @@ def get_allow_undefined_args(self) -> T.List[str]:
     def get_lto_args(self) -> T.List[str]:
         return ['-flto']
 
-    def sanitizer_args(self, value: str) -> T.List[str]:
-        if value == 'none':
-            return []
-        return ['-fsanitize=' + value]
+    def sanitizer_args(self, value: T.List[str]) -> T.List[str]:
+        if not value:
+            return value
+        return [f'-fsanitize={",".join(value)}']
 
     def get_coverage_args(self) -> T.List[str]:
         return ['--coverage']
@@ -758,10 +758,10 @@ def get_link_whole_for(self, args: T.List[str]) -> T.List[str]:
     def get_coverage_args(self) -> T.List[str]:
         return ['--coverage']
 
-    def sanitizer_args(self, value: str) -> T.List[str]:
-        if value == 'none':
-            return []
-        return ['-fsanitize=' + value]
+    def sanitizer_args(self, value: T.List[str]) -> T.List[str]:
+        if not value:
+            return value
+        return [f'-fsanitize={",".join(value)}']
 
     def no_undefined_args(self) -> T.List[str]:
         return self._apply_prefix('-undefined,error')

mesonbuild/modules/gnome.py

@@ -918,9 +918,9 @@ def _get_langs_compilers_flags(state: 'ModuleState', langs_compilers: T.List[T.T
             if state.project_args.get(lang):
                 cflags += state.project_args[lang]
             if mesonlib.OptionKey('b_sanitize') in compiler.base_options:
-                sanitize = state.environment.coredata.options[mesonlib.OptionKey('b_sanitize')].value
+                sanitize: T.List[str] = state.environment.coredata.options[mesonlib.OptionKey('b_sanitize')].value
+                assert isinstance(sanitize, list), 'for mypy'
                 cflags += compiler.sanitizer_compile_args(sanitize)
-                sanitize = sanitize.split(',')
                 # These must be first in ldflags
                 if 'address' in sanitize:
                     internal_ldflags += ['-lasan']

test cases/linuxlike/16 sanitizers/meson.build

@@ -0,0 +1,4 @@
+project('sanitizer', 'c')
+
+subproject('new_behavior')
+subproject('old_behavior')

test cases/linuxlike/16 sanitizers/subprojects/new_behavior/meson.build

@@ -0,0 +1,10 @@
+project(
+  'sanitizer-new-behavior',
+  'c',
+  # XXX: this should be 0.62, but there's no way to test it until we actuall bump to 0.62…
+  meson_version : '>= 0.61.99',
+)
+
+sanitize = get_option('b_sanitize')
+
+assert(sanitize == ['undefined', 'address'], ','.join(sanitize))

test cases/linuxlike/16 sanitizers/subprojects/old_behavior/meson.build

@@ -0,0 +1,9 @@
+project(
+  'sanitizer-old-behavior',
+  'c',
+  meson_version : '>= 0.55',
+)
+
+sanitize = get_option('b_sanitize')
+
+assert(sanitize == 'address,undefined', sanitize)

test cases/linuxlike/16 sanitizers/test.json

@@ -0,0 +1,7 @@
+{
+  "matrix": {
+    "options": {
+      "b_sanitize": [{ "val": ["undefined", "address"] }]
+    }
+  }
+}

unittests/allplatformstests.py

@@ -2291,7 +2291,7 @@ def test_command_line(self):
             obj = mesonbuild.coredata.load(self.builddir)
             self.assertEqual(obj.options[OptionKey('bindir')].value, 'bar')
             self.assertEqual(obj.options[OptionKey('buildtype')].value, 'release')
-            self.assertEqual(obj.options[OptionKey('b_sanitize')].value, 'thread')
+            self.assertEqual(obj.options[OptionKey('b_sanitize')].value, ['thread'])
             self.assertEqual(obj.options[OptionKey('args', lang='c')].value, ['-Dbar'])
             self.setconf(['--bindir=bar', '--bindir=foo',
                           '-Dbuildtype=release', '-Dbuildtype=plain',
@@ -2300,7 +2300,7 @@ def test_command_line(self):
             obj = mesonbuild.coredata.load(self.builddir)
             self.assertEqual(obj.options[OptionKey('bindir')].value, 'foo')
             self.assertEqual(obj.options[OptionKey('buildtype')].value, 'plain')
-            self.assertEqual(obj.options[OptionKey('b_sanitize')].value, 'address')
+            self.assertEqual(obj.options[OptionKey('b_sanitize')].value, ['address'])
             self.assertEqual(obj.options[OptionKey('args', lang='c')].value, ['-Dfoo'])
             self.wipe()
         except KeyError: