Merge pull request #1408 from centricular/detectcompilersbetter

More fixes to compiler detection

12 files changed, 238 insertions, 173 deletions

diff --git a/.travis.yml b/.travis.yml
index 2acb908..b3346a1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -40,5 +40,5 @@ script:
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then echo FROM jpakkane/mesonci:yakkety > Dockerfile; fi
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then echo ADD . /root >> Dockerfile; fi
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then docker build -t withgit .; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then docker run withgit /bin/sh -c "cd /root && TRAVIS=true CC=$CC CXX=$CXX ./run_tests.py -- $MESON_ARGS"; fi
-  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then SDKROOT=$(xcodebuild -version -sdk macosx Path) ./run_tests.py --backend=ninja -- $MESON_ARGS ; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then docker run withgit /bin/sh -c "cd /root && TRAVIS=true CC=$CC CXX=$CXX OBJC=$CC OBJCXX=$CXX ./run_tests.py -- $MESON_ARGS"; fi
+  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then SDKROOT=$(xcodebuild -version -sdk macosx Path) OBJC=$CC OBJCXX=$CXX ./run_tests.py --backend=ninja -- $MESON_ARGS ; fi
diff --git a/authors.txt b/authors.txt
index c75f84b..85d58c3 100644
--- a/authors.txt
+++ b/authors.txt
@@ -65,3 +65,4 @@ Mike Sinkovsky
 Dima Krasner
 Fabio Porcedda
 Rodrigo Lourenço
+Sebastian Stang
diff --git a/mesonbuild/compilers.py b/mesonbuild/compilers.py
index 30f2608..8c2bb92 100644
--- a/mesonbuild/compilers.py
+++ b/mesonbuild/compilers.py
@@ -2404,11 +2404,9 @@ class GnuCPPCompiler(GnuCompiler, CPPCompiler):
 
 class GnuObjCCompiler(GnuCompiler, ObjCCompiler):
 
-    def __init__(self, exelist, version, is_cross, exe_wrapper=None, defines=None):
+    def __init__(self, exelist, version, gcc_type, is_cross, exe_wrapper=None, defines=None):
         ObjCCompiler.__init__(self, exelist, version, is_cross, exe_wrapper)
-        # Not really correct, but GNU objc is only used on non-OSX non-win. File a bug
-        # if this breaks your use case.
-        GnuCompiler.__init__(self, GCC_STANDARD, defines)
+        GnuCompiler.__init__(self, gcc_type, defines)
         default_warn_args = ['-Wall', '-Winvalid-pch']
         self.warn_args = {'1': default_warn_args,
                           '2': default_warn_args + ['-Wextra'],
@@ -2416,11 +2414,9 @@ class GnuObjCCompiler(GnuCompiler, ObjCCompiler):
 
 class GnuObjCPPCompiler(GnuCompiler, ObjCPPCompiler):
 
-    def __init__(self, exelist, version, is_cross, exe_wrapper=None, defines=None):
+    def __init__(self, exelist, version, gcc_type, is_cross, exe_wrapper=None, defines=None):
         ObjCPPCompiler.__init__(self, exelist, version, is_cross, exe_wrapper)
-        # Not really correct, but GNU objc is only used on non-OSX non-win. File a bug
-        # if this breaks your use case.
-        GnuCompiler.__init__(self, GCC_STANDARD, defines)
+        GnuCompiler.__init__(self, gcc_type, defines)
         default_warn_args = ['-Wall', '-Winvalid-pch', '-Wnon-virtual-dtor']
         self.warn_args = {'1': default_warn_args,
                           '2': default_warn_args + ['-Wextra'],
@@ -2549,13 +2545,13 @@ class ClangCPPCompiler(ClangCompiler, CPPCompiler):
 
 class ClangObjCCompiler(ClangCompiler, GnuObjCCompiler):
     def __init__(self, exelist, version, cltype, is_cross, exe_wrapper=None):
-        GnuObjCCompiler.__init__(self, exelist, version, is_cross, exe_wrapper)
+        GnuObjCCompiler.__init__(self, exelist, version, cltype, is_cross, exe_wrapper)
         ClangCompiler.__init__(self, cltype)
         self.base_options = ['b_pch', 'b_lto', 'b_pgo', 'b_sanitize', 'b_coverage']
 
 class ClangObjCPPCompiler(ClangCompiler, GnuObjCPPCompiler):
     def __init__(self, exelist, version, cltype, is_cross, exe_wrapper=None):
-        GnuObjCPPCompiler.__init__(self, exelist, version, is_cross, exe_wrapper)
+        GnuObjCPPCompiler.__init__(self, exelist, version, cltype, is_cross, exe_wrapper)
         ClangCompiler.__init__(self, cltype)
         self.base_options = ['b_pch', 'b_lto', 'b_pgo', 'b_sanitize', 'b_coverage']
 
diff --git a/mesonbuild/environment.py b/mesonbuild/environment.py
index cbfa3ec..88dc4cf 100644
--- a/mesonbuild/environment.py
+++ b/mesonbuild/environment.py
@@ -367,10 +367,13 @@ class Environment:
         # We ignore Cygwin for now, and treat it as a standard GCC
         return GCC_STANDARD
 
-    def detect_c_compiler(self, want_cross):
-        evar = 'CC'
+    def _get_compilers(self, lang, evar, want_cross):
+        '''
+        The list of compilers is detected in the exact same way for
+        C, C++, ObjC, ObjC++, Fortran so consolidate it here.
+        '''
         if self.is_cross_build() and want_cross:
-            compilers = mesonlib.stringintlistify(self.cross_info.config['binaries']['c'])
+            compilers = [mesonlib.stringlistify(self.cross_info.config['binaries'][lang])]
             ccache = []
             is_cross = True
             if self.cross_info.need_exe_wrapper():
@@ -378,22 +381,33 @@ class Environment:
             else:
                 exe_wrap = []
         elif evar in os.environ:
-            compilers = shlex.split(os.environ[evar])
+            compilers = [shlex.split(os.environ[evar])]
             ccache = []
             is_cross = False
             exe_wrap = None
         else:
-            compilers = self.default_c
+            compilers = getattr(self, 'default_' + lang)
             ccache = self.detect_ccache()
             is_cross = False
             exe_wrap = None
+        return compilers, ccache, is_cross, exe_wrap
+
+    def _handle_compiler_exceptions(self, exceptions, compilers):
+        errmsg = 'Unknown compiler(s): ' + str(compilers)
+        if exceptions:
+            errmsg += '\nThe follow exceptions were encountered:'
+            for (c, e) in exceptions.items():
+                errmsg += '\nRunning "{0}" gave "{1}"'.format(c, e)
+        raise EnvironmentException(errmsg)
+
+    def _detect_c_or_cpp_compiler(self, lang, evar, want_cross):
         popen_exceptions = {}
+        compilers, ccache, is_cross, exe_wrap = self._get_compilers(lang, evar, want_cross)
         for compiler in compilers:
             if isinstance(compiler, str):
                 compiler = [compiler]
             try:
-                basename = os.path.basename(compiler[-1]).lower()
-                if basename == 'cl' or basename == 'cl.exe':
+                if 'cl' in compiler or 'cl.exe' in compiler:
                     arg = '/?'
                 else:
                     arg = '--version'
@@ -409,49 +423,39 @@ class Environment:
                     continue
                 gtype = self.get_gnu_compiler_type(defines)
                 version = self.get_gnu_version_from_defines(defines)
-                return GnuCCompiler(ccache + compiler, version, gtype, is_cross, exe_wrap, defines)
+                cls = GnuCCompiler if lang == 'c' else GnuCPPCompiler
+                return cls(ccache + compiler, version, gtype, is_cross, exe_wrap, defines)
             if 'clang' in out:
                 if 'Apple' in out or for_darwin(want_cross, self):
                     cltype = CLANG_OSX
                 else:
                     cltype = CLANG_STANDARD
-                return ClangCCompiler(ccache + compiler, version, cltype, is_cross, exe_wrap)
+                cls = ClangCCompiler if lang == 'c' else ClangCPPCompiler
+                return cls(ccache + compiler, version, cltype, is_cross, exe_wrap)
             if 'Microsoft' in out or 'Microsoft' in err:
                 # Visual Studio prints version number to stderr but
                 # everything else to stdout. Why? Lord only knows.
                 version = search_version(err)
-                return VisualStudioCCompiler(compiler, version, is_cross, exe_wrap)
+                cls = VisualStudioCCompiler if lang == 'c' else VisualStudioCPPCompiler
+                return cls(compiler, version, is_cross, exe_wrap)
             if '(ICC)' in out:
                 # TODO: add microsoft add check OSX
                 inteltype = ICC_STANDARD
-                return IntelCCompiler(ccache + compiler, version, inteltype, is_cross, exe_wrap)
-        errmsg = 'Unknown compiler(s): ' + str(compilers)
-        if popen_exceptions:
-            errmsg += '\nThe follow exceptions were encountered:'
-            for (c, e) in popen_exceptions.items():
-                errmsg += '\nRunning "{0}" gave "{1}"'.format(c, e)
-        raise EnvironmentException(errmsg)
+                cls = IntelCCompiler if lang == 'c' else IntelCPPCompiler
+                return cls(ccache + compiler, version, inteltype, is_cross, exe_wrap)
+        self._handle_compiler_exceptions(popen_exceptions, compilers)
+
+    def detect_c_compiler(self, want_cross):
+        return self._detect_c_or_cpp_compiler('c', 'CC', want_cross)
+
+    def detect_cpp_compiler(self, want_cross):
+        return self._detect_c_or_cpp_compiler('cpp', 'CXX', want_cross)
 
     def detect_fortran_compiler(self, want_cross):
-        evar = 'FC'
-        if self.is_cross_build() and want_cross:
-            compilers = meson.stringlistify(self.cross_info['fortran'])
-            is_cross = True
-            if self.cross_info.need_exe_wrapper():
-                exe_wrap = self.cross_info.get('exe_wrapper', None)
-            else:
-                exe_wrap = []
-        elif evar in os.environ:
-            compilers = os.environ[evar].split()
-            is_cross = False
-            exe_wrap = None
-        else:
-            compilers = self.default_fortran
-            is_cross = False
-            exe_wrap = None
         popen_exceptions = {}
+        compilers, ccache, is_cross, exe_wrap = self._get_compilers('fortran', 'FC', want_cross)
         for compiler in compilers:
-            if not isinstance(compiler, list):
+            if isinstance(compiler, str):
                 compiler = [compiler]
             for arg in ['--version', '-V']:
                 try:
@@ -492,12 +496,7 @@ class Environment:
 
                 if 'NAG Fortran' in err:
                     return NAGFortranCompiler(compiler, version, is_cross, exe_wrap)
-        errmsg = 'Unknown compiler(s): ' + str(compilers)
-        if popen_exceptions:
-            errmsg += '\nThe follow exceptions were encountered:'
-            for (c, e) in popen_exceptions.items():
-                errmsg += '\nRunning "{0}" gave "{1}"'.format(c, e)
-        raise EnvironmentException(errmsg)
+        self._handle_compiler_exceptions(popen_exceptions, compilers)
 
     def get_scratch_dir(self):
         return self.scratch_dir
@@ -506,40 +505,16 @@ class Environment:
         path = os.path.split(__file__)[0]
         return os.path.join(path, 'depfixer.py')
 
-    def detect_cpp_compiler(self, want_cross):
-        evar = 'CXX'
-        if self.is_cross_build() and want_cross:
-            compilers = mesonlib.stringlistify(self.cross_info.config['binaries']['cpp'])
-            ccache = []
-            is_cross = True
-            if self.cross_info.need_exe_wrapper():
-                exe_wrap = self.cross_info.config['binaries'].get('exe_wrapper', None)
-            else:
-                exe_wrap = []
-        elif evar in os.environ:
-            compilers = shlex.split(os.environ[evar])
-            ccache = []
-            is_cross = False
-            exe_wrap = None
-        else:
-            compilers = self.default_cpp
-            ccache = self.detect_ccache()
-            is_cross = False
-            exe_wrap = None
+    def detect_objc_compiler(self, want_cross):
         popen_exceptions = {}
+        compilers, ccache, is_cross, exe_wrap = self._get_compilers('objc', 'OBJC', want_cross)
         for compiler in compilers:
             if isinstance(compiler, str):
                 compiler = [compiler]
-            basename = os.path.basename(compiler[-1]).lower()
-            if basename == 'cl' or basename == 'cl.exe':
-                arg = '/?'
-            else:
-                arg = '--version'
             try:
-                p, out, err = Popen_safe(compiler + [arg])
-            except OSError as e:
+                p, out, err = Popen_safe(compiler + ['--version'])
+            except OSError:
                 popen_exceptions[' '.join(compiler + [arg])] = e
-                continue
             version = search_version(out)
             if 'Free Software Foundation' in out:
                 defines = self.get_gnu_compiler_defines(compiler)
@@ -548,75 +523,37 @@ class Environment:
                     continue
                 gtype = self.get_gnu_compiler_type(defines)
                 version = self.get_gnu_version_from_defines(defines)
-                return GnuCPPCompiler(ccache + compiler, version, gtype, is_cross, exe_wrap, defines)
-            if 'clang' in out:
-                if 'Apple' in out:
-                    cltype = CLANG_OSX
-                else:
-                    cltype = CLANG_STANDARD
-                return ClangCPPCompiler(ccache + compiler, version, cltype, is_cross, exe_wrap)
-            if 'Microsoft' in out or 'Microsoft' in err:
-                version = search_version(err)
-                return VisualStudioCPPCompiler(compiler, version, is_cross, exe_wrap)
-            if '(ICC)' in out:
-                # TODO: add microsoft add check OSX
-                inteltype = ICC_STANDARD
-                return IntelCPPCompiler(ccache + compiler, version, inteltype, is_cross, exe_wrap)
-        errmsg = 'Unknown compiler(s): "' + ', '.join(compilers) + '"'
-        if popen_exceptions:
-            errmsg += '\nThe follow exceptions were encountered:'
-            for (c, e) in popen_exceptions.items():
-                errmsg += '\nRunning "{0}" gave "{1}"'.format(c, e)
-        raise EnvironmentException(errmsg)
-
-    def detect_objc_compiler(self, want_cross):
-        if self.is_cross_build() and want_cross:
-            exelist = mesonlib.stringlistify(self.cross_info['objc'])
-            is_cross = True
-            if self.cross_info.need_exe_wrapper():
-                exe_wrap = self.cross_info.get('exe_wrapper', None)
-            else:
-                exe_wrap = []
-        else:
-            exelist = self.get_objc_compiler_exelist()
-            is_cross = False
-            exe_wrap = None
-        try:
-            p, out, err = Popen_safe(exelist + ['--version'])
-        except OSError:
-            raise EnvironmentException('Could not execute ObjC compiler "%s"' % ' '.join(exelist))
-        version = search_version(out)
-        if 'Free Software Foundation' in out:
-            defines = self.get_gnu_compiler_defines(exelist)
-            version = self.get_gnu_version_from_defines(defines)
-            return GnuObjCCompiler(exelist, version, is_cross, exe_wrap, defines)
-        if out.startswith('Apple LLVM'):
-            return ClangObjCCompiler(exelist, version, CLANG_OSX, is_cross, exe_wrap)
-        raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
+                return GnuObjCCompiler(ccache + compiler, version, gtype, is_cross, exe_wrap, defines)
+            if out.startswith('Apple LLVM'):
+                return ClangObjCCompiler(ccache + compiler, version, CLANG_OSX, is_cross, exe_wrap)
+            if out.startswith('clang'):
+                return ClangObjCCompiler(ccache + compiler, version, CLANG_STANDARD, is_cross, exe_wrap)
+        self._handle_compiler_exceptions(popen_exceptions, compilers)
 
     def detect_objcpp_compiler(self, want_cross):
-        if self.is_cross_build() and want_cross:
-            exelist = mesonlib.stringlistify(self.cross_info['objcpp'])
-            is_cross = True
-            if self.cross_info.need_exe_wrapper():
-                exe_wrap = self.cross_info.get('exe_wrapper', None)
-            else:
-                exe_wrap = []
-        else:
-            exelist = self.get_objcpp_compiler_exelist()
-            is_cross = False
-            exe_wrap = None
-        try:
-            p, out, err = Popen_safe(exelist + ['--version'])
-        except OSError:
-            raise EnvironmentException('Could not execute ObjC++ compiler "%s"' % ' '.join(exelist))
-        version = search_version(out)
-        if 'Free Software Foundation' in out:
-            defines = self.get_gnu_compiler_defines(exelist)
-            return GnuObjCPPCompiler(exelist, version, is_cross, exe_wrap, defines)
-        if out.startswith('Apple LLVM'):
-            return ClangObjCPPCompiler(exelist, version, CLANG_OSX, is_cross, exe_wrap)
-        raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
+        popen_exceptions = {}
+        compilers, ccache, is_cross, exe_wrap = self._get_compilers('objcpp', 'OBJCXX', want_cross)
+        for compiler in compilers:
+            if isinstance(compiler, str):
+                compiler = [compiler]
+            try:
+                p, out, err = Popen_safe(compiler + ['--version'])
+            except OSError:
+                popen_exceptions[' '.join(compiler + [arg])] = e
+            version = search_version(out)
+            if 'Free Software Foundation' in out:
+                defines = self.get_gnu_compiler_defines(compiler)
+                if not defines:
+                    popen_exceptions[compiler] = 'no pre-processor defines'
+                    continue
+                gtype = self.get_gnu_compiler_type(defines)
+                version = self.get_gnu_version_from_defines(defines)
+                return GnuObjCPPCompiler(ccache + compiler, version, gtype, is_cross, exe_wrap, defines)
+            if out.startswith('Apple LLVM'):
+                return ClangObjCPPCompiler(ccache + compiler, version, CLANG_OSX, is_cross, exe_wrap)
+            if out.startswith('clang'):
+                return ClangObjCPPCompiler(ccache + compiler, version, CLANG_STANDARD, is_cross, exe_wrap)
+        self._handle_compiler_exceptions(popen_exceptions, compilers)
 
     def detect_java_compiler(self):
         exelist = ['javac']
@@ -711,30 +648,31 @@ class Environment:
     def detect_static_linker(self, compiler):
         if compiler.is_cross:
             linker = self.cross_info.config['binaries']['ar']
+            if isinstance(linker, str):
+                linker = [linker]
         else:
             evar = 'AR'
             if evar in os.environ:
-                linker = os.environ[evar].strip()
+                linker = shlex.split(os.environ[evar])
             elif isinstance(compiler, VisualStudioCCompiler):
-                linker = self.vs_static_linker
+                linker = [self.vs_static_linker]
             else:
-                linker = self.default_static_linker
-        basename = os.path.basename(linker).lower()
-        if basename == 'lib' or basename == 'lib.exe':
+                linker = [self.default_static_linker]
+        if 'lib' in linker or 'lib.exe' in linker:
             arg = '/?'
         else:
             arg = '--version'
         try:
-            p, out, err = Popen_safe([linker, arg])
+            p, out, err = Popen_safe(linker + [arg])
         except OSError:
-            raise EnvironmentException('Could not execute static linker "%s".' % linker)
+            raise EnvironmentException('Could not execute static linker "%s".' % ' '.join(linker))
         if '/OUT:' in out or '/OUT:' in err:
-            return VisualStudioLinker([linker])
+            return VisualStudioLinker(linker)
         if p.returncode == 0:
-            return ArLinker([linker])
+            return ArLinker(linker)
         if p.returncode == 1 and err.startswith('usage'): # OSX
-            return ArLinker([linker])
-        raise EnvironmentException('Unknown static linker "%s"' % linker)
+            return ArLinker(linker)
+        raise EnvironmentException('Unknown static linker "%s"' % ' '.join(linker))
 
     def detect_ccache(self):
         try:
@@ -747,20 +685,6 @@ class Environment:
             cmdlist = []
         return cmdlist
 
-    def get_objc_compiler_exelist(self):
-        ccachelist = self.detect_ccache()
-        evar = 'OBJCC'
-        if evar in os.environ:
-            return os.environ[evar].split()
-        return ccachelist + self.default_objc
-
-    def get_objcpp_compiler_exelist(self):
-        ccachelist = self.detect_ccache()
-        evar = 'OBJCXX'
-        if evar in os.environ:
-            return os.environ[evar].split()
-        return ccachelist + self.default_objcpp
-
     def get_source_dir(self):
         return self.source_dir
 
diff --git a/run_unittests.py b/run_unittests.py
index 16ff354..f800d03 100755
--- a/run_unittests.py
+++ b/run_unittests.py
@@ -24,7 +24,7 @@ from pathlib import PurePath
 import mesonbuild.compilers
 import mesonbuild.environment
 import mesonbuild.mesonlib
-from mesonbuild.mesonlib import is_windows
+from mesonbuild.mesonlib import is_windows, is_osx
 from mesonbuild.environment import detect_ninja, Environment
 from mesonbuild.dependencies import PkgConfigDependency, ExternalProgram
 
@@ -725,6 +725,107 @@ class AllPlatformTests(BasePlatformTests):
         # target internal dependency include_directories: source dir
         self.assertPathBasenameEqual(incs[7], 'sub1')
 
+    def test_compiler_detection(self):
+        '''
+        Test that automatic compiler detection and setting from the environment
+        both work just fine. This is needed because while running project tests
+        and other unit tests, we always read CC/CXX/etc from the environment.
+        '''
+        gnu = mesonbuild.compilers.GnuCompiler
+        clang = mesonbuild.compilers.ClangCompiler
+        intel = mesonbuild.compilers.IntelCompiler
+        msvc = mesonbuild.compilers.VisualStudioCCompiler
+        ar = mesonbuild.compilers.ArLinker
+        lib = mesonbuild.compilers.VisualStudioLinker
+        langs = [('c', 'CC'), ('cpp', 'CXX')]
+        if not is_windows():
+            langs += [('objc', 'OBJC'), ('objcpp', 'OBJCXX')]
+        testdir = os.path.join(self.unit_test_dir, '5 compiler detection')
+        env = Environment(testdir, self.builddir, self.meson_command,
+                          get_fake_options(self.prefix), [])
+        for lang, evar in langs:
+            evalue = None
+            # Detect with evar and do sanity checks on that
+            if evar in os.environ:
+                ecc = getattr(env, 'detect_{}_compiler'.format(lang))(False)
+                elinker = env.detect_static_linker(ecc)
+                # Pop it so we don't use it for the next detection
+                evalue = os.environ.pop(evar)
+                # Very rough/strict heuristics. Would never work for actual
+                # compiler detection, but should be ok for the tests.
+                if os.path.basename(evalue).startswith('g'):
+                    self.assertIsInstance(ecc, gnu)
+                    self.assertIsInstance(elinker, ar)
+                elif 'clang' in os.path.basename(evalue):
+                    self.assertIsInstance(ecc, clang)
+                    self.assertIsInstance(elinker, ar)
+                elif os.path.basename(evalue).startswith('ic'):
+                    self.assertIsInstance(ecc, intel)
+                    self.assertIsInstance(elinker, ar)
+                elif os.path.basename(evalue).startswith('cl'):
+                    self.assertIsInstance(ecc, msvc)
+                    self.assertIsInstance(elinker, lib)
+                else:
+                    raise AssertionError('Unknown compiler {!r}'.format(evalue))
+                # Check that we actually used the evalue correctly as the compiler
+                self.assertEqual(ecc.get_exelist(), shlex.split(evalue))
+            # Do auto-detection of compiler based on platform, PATH, etc.
+            cc = getattr(env, 'detect_{}_compiler'.format(lang))(False)
+            linker = env.detect_static_linker(cc)
+            # Check compiler type
+            if isinstance(cc, gnu):
+                self.assertIsInstance(linker, ar)
+                if is_osx():
+                    self.assertEqual(cc.gcc_type, mesonbuild.compilers.GCC_OSX)
+                elif is_windows():
+                    self.assertEqual(cc.gcc_type, mesonbuild.compilers.GCC_MINGW)
+                else:
+                    self.assertEqual(cc.gcc_type, mesonbuild.compilers.GCC_STANDARD)
+            if isinstance(cc, clang):
+                self.assertIsInstance(linker, ar)
+                if is_osx():
+                    self.assertEqual(cc.clang_type, mesonbuild.compilers.CLANG_OSX)
+                elif is_windows():
+                    # Not implemented yet
+                    self.assertEqual(cc.clang_type, mesonbuild.compilers.CLANG_WIN)
+                else:
+                    self.assertEqual(cc.clang_type, mesonbuild.compilers.CLANG_STANDARD)
+            if isinstance(cc, intel):
+                self.assertIsInstance(linker, ar)
+                if is_osx():
+                    self.assertEqual(cc.icc_type, mesonbuild.compilers.ICC_OSX)
+                elif is_windows():
+                    self.assertEqual(cc.icc_type, mesonbuild.compilers.ICC_WIN)
+                else:
+                    self.assertEqual(cc.icc_type, mesonbuild.compilers.ICC_STANDARD)
+            if isinstance(cc, msvc):
+                self.assertTrue(is_windows())
+                self.assertIsInstance(linker, lib)
+                self.assertEqual(cc.id, 'msvc')
+            # Set evar ourselves to a wrapper script that just calls the same
+            # exelist + some argument. This is meant to test that setting
+            # something like `ccache gcc -pipe` or `distcc ccache gcc` works.
+            wrapper = os.path.join(testdir, 'compiler wrapper.py')
+            wrappercc = [sys.executable, wrapper] + cc.get_exelist() + cc.get_always_args()
+            wrappercc_s = ''
+            for w in wrappercc:
+                wrappercc_s += shlex.quote(w) + ' '
+            os.environ[evar] = wrappercc_s
+            wcc = getattr(env, 'detect_{}_compiler'.format(lang))(False)
+            # Check static linker too
+            wrapperlinker = [sys.executable, wrapper] + linker.get_exelist() + linker.get_always_args()
+            wrapperlinker_s = ''
+            for w in wrapperlinker:
+                wrapperlinker_s += shlex.quote(w) + ' '
+            os.environ['AR'] = wrapperlinker_s
+            wlinker = env.detect_static_linker(wcc)
+            # Must be the same type since it's a wrapper around the same exelist
+            self.assertIs(type(cc), type(wcc))
+            self.assertIs(type(linker), type(wlinker))
+            # Ensure that the exelist is correct
+            self.assertEqual(wcc.get_exelist(), wrappercc)
+            self.assertEqual(wlinker.get_exelist(), wrapperlinker)
+
 
 class WindowsTests(BasePlatformTests):
     '''
diff --git a/test cases/objc/2 nsstring/meson.build b/test cases/objc/2 nsstring/meson.build
index bc997bc..ec496a2 100644
--- a/test cases/objc/2 nsstring/meson.build
+++ b/test cases/objc/2 nsstring/meson.build
@@ -4,6 +4,9 @@ if host_machine.system() == 'darwin'
   dep = dependency('appleframeworks', modules : 'foundation')
 else
   dep = dependency('gnustep')
+  if host_machine.system() == 'linux' and meson.get_compiler('objc').get_id() == 'clang'
+    error('MESON_SKIP_TEST: GNUstep is broken on Linux with Clang')
+  endif
 endif
 exe = executable('stringprog', 'stringprog.m', dependencies : dep)
 test('stringtest', exe)
diff --git a/test cases/unit/5 compiler detection/compiler wrapper.py b/test cases/unit/5 compiler detection/compiler wrapper.py
new file mode 100644
index 0000000..fedd343
--- /dev/null
+++ b/test cases/unit/5 compiler detection/compiler wrapper.py
@@ -0,0 +1,6 @@
+#!/usr/bin/env python3
+
+import sys
+import subprocess
+
+sys.exit(subprocess.call(sys.argv[1:]))
diff --git a/test cases/unit/5 compiler detection/meson.build b/test cases/unit/5 compiler detection/meson.build
new file mode 100644
index 0000000..5491c64
--- /dev/null
+++ b/test cases/unit/5 compiler detection/meson.build
@@ -0,0 +1,8 @@
+project('trivial test',
+        ['c', 'cpp', 'objc', 'objcpp'],
+        meson_version : '>=0.27.0')
+
+executable('trivialc', 'trivial.c')
+executable('trivialcpp', 'trivial.cpp')
+executable('trivialobjc', 'trivial.m')
+executable('trivialobjcpp', 'trivial.mm')
diff --git a/test cases/unit/5 compiler detection/trivial.c b/test cases/unit/5 compiler detection/trivial.c
new file mode 100644
index 0000000..24ac454
--- /dev/null
+++ b/test cases/unit/5 compiler detection/trivial.c
@@ -0,0 +1,6 @@
+#include<stdio.h>
+
+int main(int argc, char **argv) {
+    printf("Trivial test is working.\n");
+    return 0;
+}
diff --git a/test cases/unit/5 compiler detection/trivial.cc b/test cases/unit/5 compiler detection/trivial.cc
new file mode 100644
index 0000000..8aa907b
--- /dev/null
+++ b/test cases/unit/5 compiler detection/trivial.cc
@@ -0,0 +1,6 @@
+#include<iostream>
+
+int main(int argc, char **argv) {
+  std::cout << "C++ seems to be working." << std::endl;
+  return 0;
+}
diff --git a/test cases/unit/5 compiler detection/trivial.m b/test cases/unit/5 compiler detection/trivial.m
new file mode 100644
index 0000000..f2e2315
--- /dev/null
+++ b/test cases/unit/5 compiler detection/trivial.m
@@ -0,0 +1,5 @@
+#import<stdio.h>
+
+int main(int argc, char **argv) {
+    return 0;
+}
\ No newline at end of file
diff --git a/test cases/unit/5 compiler detection/trivial.mm b/test cases/unit/5 compiler detection/trivial.mm
new file mode 100644
index 0000000..927e810
--- /dev/null
+++ b/test cases/unit/5 compiler detection/trivial.mm
@@ -0,0 +1,9 @@
+#import<stdio.h>
+
+class MyClass {
+};
+
+int main(int argc, char **argv) {
+  return 0;
+}
+