Correctly handle platform-specific LDFLAGS options

mesonbuild/backend/ninjabackend.py

@@ -2385,7 +2385,7 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
 
         build_dir = self.environment.get_build_dir()
         # the following loop sometimes consumes two items from command in one pass
-        it = iter(commands)
+        it = iter(linker.native_args_to_unix(commands))
         for item in it:
             if item in internal and not item.startswith('-'):
                 continue

mesonbuild/compilers/compilers.py

@@ -900,6 +900,11 @@ class Compiler:
         "Always returns a copy that can be independently mutated"
         return args[:]
 
+    @classmethod
+    def native_args_to_unix(cls, args: typing.List[str]) -> typing.List[str]:
+        "Always returns a copy that can be independently mutated"
+        return args[:]
+
     def find_library(self, *args, **kwargs):
         raise EnvironmentException('Language {} does not support library finding.'.format(self.get_display_language()))
 

mesonbuild/compilers/mixins/visualstudio.py

@@ -234,6 +234,18 @@ class VisualStudioLikeCompiler(metaclass=abc.ABCMeta):
             result.append(i)
         return result
 
+    @classmethod
+    def native_args_to_unix(cls, args: typing.List[str]) -> typing.List[str]:
+        result = []
+        for arg in args:
+            if arg.startswith('/LIBPATH:'):
+                result.append('-L' + arg[9:])
+            elif arg.endswith(('.a', '.lib')) and not os.path.isabs(arg):
+                result.append('-l' + arg)
+            else:
+                result.append(arg)
+        return result
+
     def get_werror_args(self) -> typing.List[str]:
         return ['/WX']
 

mesonbuild/linkers.py

@@ -69,7 +69,11 @@ class StaticLinker:
 
     @classmethod
     def unix_args_to_native(cls, args: typing.List[str]) -> typing.List[str]:
-        return args
+        return args[:]
+
+    @classmethod
+    def native_args_to_unix(cls, args: typing.List[str]) -> typing.List[str]:
+        return args[:]
 
     def get_link_debugfile_args(self, targetfile: str) -> typing.List[str]:
         # Static libraries do not have PDB files
@@ -106,6 +110,11 @@ class VisualStudioLikeLinker:
         from .compilers import VisualStudioCCompiler
         return VisualStudioCCompiler.unix_args_to_native(args)
 
+    @classmethod
+    def native_args_to_unix(cls, args: typing.List[str]) -> typing.List[str]:
+        from .compilers import VisualStudioCCompiler
+        return VisualStudioCCompiler.native_args_to_unix(args)
+
 
 class VisualStudioLinker(VisualStudioLikeLinker, StaticLinker):
 

run_unittests.py

@@ -3079,47 +3079,62 @@ recommended as it is not supported on some platforms''')
         Test that meson adds dependencies for libraries based on the final
         linker command line.
         '''
-        # build library
         testdirbase = os.path.join(self.unit_test_dir, '29 guessed linker dependencies')
         testdirlib = os.path.join(testdirbase, 'lib')
+
         extra_args = None
+        libdir_flags = ['-L']
         env = get_fake_env(testdirlib, self.builddir, self.prefix)
-        if env.detect_c_compiler(MachineChoice.HOST).get_id() not in {'msvc', 'clang-cl', 'intel-cl'}:
+        if env.detect_c_compiler(MachineChoice.HOST).get_id() in {'msvc', 'clang-cl', 'intel-cl'}:
+            # msvc-like compiler, also test it with msvc-specific flags
+            libdir_flags += ['/LIBPATH:']
+        else:
             # static libraries are not linkable with -l with msvc because meson installs them
             # as .a files which unix_args_to_native will not know as it expects libraries to use
             # .lib as extension. For a DLL the import library is installed as .lib. Thus for msvc
             # this tests needs to use shared libraries to test the path resolving logic in the
             # dependency generation code path.
             extra_args = ['--default-library', 'static']
-        self.init(testdirlib, extra_args=extra_args)
-        self.build()
-        self.install()
-        libbuilddir = self.builddir
-        installdir = self.installdir
-        libdir = os.path.join(self.installdir, self.prefix.lstrip('/').lstrip('\\'), 'lib')
 
-        # build user of library
-        self.new_builddir()
-        # replace is needed because meson mangles platform pathes passed via LDFLAGS
-        self.init(os.path.join(testdirbase, 'exe'),
-                  override_envvars={"LDFLAGS": '-L{}'.format(libdir.replace('\\', '/'))})
-        self.build()
-        self.assertBuildIsNoop()
+        initial_builddir = self.builddir
+        initial_installdir = self.installdir
 
-        # rebuild library
-        exebuilddir = self.builddir
-        self.installdir = installdir
-        self.builddir = libbuilddir
-        # Microsoft's compiler is quite smart about touching import libs on changes,
-        # so ensure that there is actually a change in symbols.
-        self.setconf('-Dmore_exports=true')
-        self.build()
-        self.install()
-        # no ensure_backend_detects_changes needed because self.setconf did that already
+        for libdir_flag in libdir_flags:
+            # build library
+            self.init(testdirlib, extra_args=extra_args)
+            self.build()
+            self.install()
+            libbuilddir = self.builddir
+            installdir = self.installdir
+            libdir = os.path.join(self.installdir, self.prefix.lstrip('/').lstrip('\\'), 'lib')
+
+            # build user of library
+            self.new_builddir()
+            # replace is needed because meson mangles platform pathes passed via LDFLAGS
+            self.init(os.path.join(testdirbase, 'exe'),
+                      override_envvars={"LDFLAGS": '{}{}'.format(libdir_flag, libdir.replace('\\', '/'))})
+            self.build()
+            self.assertBuildIsNoop()
+
+            # rebuild library
+            exebuilddir = self.builddir
+            self.installdir = installdir
+            self.builddir = libbuilddir
+            # Microsoft's compiler is quite smart about touching import libs on changes,
+            # so ensure that there is actually a change in symbols.
+            self.setconf('-Dmore_exports=true')
+            self.build()
+            self.install()
+            # no ensure_backend_detects_changes needed because self.setconf did that already
+
+            # assert user of library will be rebuild
+            self.builddir = exebuilddir
+            self.assertRebuiltTarget('app')
+
+            # restore dirs for the next test case
+            self.installdir = initial_builddir
+            self.builddir = initial_installdir
 
-        # assert user of library will be rebuild
-        self.builddir = exebuilddir
-        self.assertRebuiltTarget('app')
 
     def test_conflicting_d_dash_option(self):
         testdir = os.path.join(self.unit_test_dir, '37 mixed command line args')