compilers/linkers: Add a representation for wasm-ld

Emscripten does have a stand alone linker, wasm-ld. This patch adds the
linker, adds detection for the linker, and removes the IsLinkerMixin for
emscripten. This is a little more correct, and makes the code a lot
cleaner and more robust.

3 files changed, 4 insertions, 24 deletions

diff --git a/mesonbuild/compilers/c.py b/mesonbuild/compilers/c.py
index f3ed9e8..e17d655 100644
--- a/mesonbuild/compilers/c.py
+++ b/mesonbuild/compilers/c.py
@@ -27,7 +27,7 @@ from .mixins.intel import IntelGnuLikeCompiler, IntelVisualStudioLikeCompiler
 from .mixins.clang import ClangCompiler
 from .mixins.elbrus import ElbrusCompiler
 from .mixins.pgi import PGICompiler
-from .mixins.islinker import BasicLinkerIsCompilerMixin, LinkerEnvVarsMixin
+from .mixins.islinker import LinkerEnvVarsMixin
 from .mixins.emscripten import EmscriptenMixin
 from .compilers import (
     gnu_winlibs,
@@ -133,7 +133,7 @@ class AppleClangCCompiler(ClangCCompiler):
     _C18_VERSION = '>=11.0.0'
 
 
-class EmscriptenCCompiler(EmscriptenMixin, BasicLinkerIsCompilerMixin, LinkerEnvVarsMixin, ClangCCompiler):
+class EmscriptenCCompiler(EmscriptenMixin, LinkerEnvVarsMixin, ClangCCompiler):
     def __init__(self, exelist, version, for_machine: MachineChoice,
                  is_cross: bool, info: 'MachineInfo', exe_wrapper=None, **kwargs):
         if not is_cross:
diff --git a/mesonbuild/compilers/cpp.py b/mesonbuild/compilers/cpp.py
index 2a244e9..db7875b 100644
--- a/mesonbuild/compilers/cpp.py
+++ b/mesonbuild/compilers/cpp.py
@@ -36,7 +36,7 @@ from .mixins.intel import IntelGnuLikeCompiler, IntelVisualStudioLikeCompiler
 from .mixins.clang import ClangCompiler
 from .mixins.elbrus import ElbrusCompiler
 from .mixins.pgi import PGICompiler
-from .mixins.islinker import BasicLinkerIsCompilerMixin, LinkerEnvVarsMixin
+from .mixins.islinker import LinkerEnvVarsMixin
 from .mixins.emscripten import EmscriptenMixin
 
 if T.TYPE_CHECKING:
@@ -201,7 +201,7 @@ class AppleClangCPPCompiler(ClangCPPCompiler):
     pass
 
 
-class EmscriptenCPPCompiler(EmscriptenMixin, BasicLinkerIsCompilerMixin, LinkerEnvVarsMixin, ClangCPPCompiler):
+class EmscriptenCPPCompiler(EmscriptenMixin, LinkerEnvVarsMixin, ClangCPPCompiler):
     def __init__(self, exelist, version, for_machine: MachineChoice,
                  is_cross: bool, info: 'MachineInfo', exe_wrapper=None, **kwargs):
         if not is_cross:
diff --git a/mesonbuild/compilers/mixins/emscripten.py b/mesonbuild/compilers/mixins/emscripten.py
index ee86ce4..10f4b25 100644
--- a/mesonbuild/compilers/mixins/emscripten.py
+++ b/mesonbuild/compilers/mixins/emscripten.py
@@ -18,7 +18,6 @@ import os.path
 import typing as T
 
 from ... import coredata
-from ...mesonlib import MesonException
 
 if T.TYPE_CHECKING:
     from ..environment import Environment
@@ -26,18 +25,6 @@ if T.TYPE_CHECKING:
 
 class EmscriptenMixin:
 
-    def get_option_link_args(self, options):
-        return []
-
-    def get_soname_args(self, *args, **kwargs):
-        raise MesonException('Emscripten does not support shared libraries.')
-
-    def get_allow_undefined_link_args(self) -> T.List[str]:
-        return ['-s', 'ERROR_ON_UNDEFINED_SYMBOLS=0']
-
-    def get_linker_output_args(self, output: str) -> T.List[str]:
-        return ['-o', output]
-
     def _get_compile_output(self, dirname, mode):
         # In pre-processor mode, the output is sent to stdout and discarded
         if mode == 'preprocess':
@@ -54,13 +41,6 @@ class EmscriptenMixin:
     def thread_flags(self, env: 'Environment') -> T.List[str]:
         return ['-s', 'USE_PTHREADS=1']
 
-    def thread_link_flags(self, env: 'Environment') -> T.List[str]:
-        args = ['-s', 'USE_PTHREADS=1']
-        count = env.coredata.compiler_options[self.for_machine]['{}_thread_count'.format(self.language)].value  # type: int
-        if count:
-            args.extend(['-s', 'PTHREAD_POOL_SIZE={}'.format(count)])
-        return args
-
     def get_options(self):
         opts = super().get_options()
         opts.update({