Factor out /emsdk/emscripten

Author: kon72

tools/system_libs.py

@@ -39,6 +39,9 @@
 # link time.
 USE_NINJA = int(os.environ.get('EMCC_USE_NINJA', '0'))
 
+# A dummy path used as a compilation directory for deterministic builds.
+DUMMY_EMSCRIPTEN_ROOT = '/emsdk/emscripten'
+
 
 def files_in_path(path, filenames):
   srcdir = utils.path_from_root(path)
@@ -472,9 +475,9 @@ def generate_ninja(self, build_dir, libname):
     if self.deterministic_paths:
       source_dir = utils.path_from_root()
       relative_source_dir = os.path.relpath(source_dir, build_dir)
-      cflags += [f'-ffile-prefix-map={source_dir}=/emsdk/emscripten',
+      cflags += [f'-ffile-prefix-map={source_dir}={DUMMY_EMSCRIPTEN_ROOT}',
                  f'-ffile-prefix-map={relative_source_dir}/=',
-                 '-fdebug-compilation-dir=/emsdk/emscripten']
+                 f'-fdebug-compilation-dir={DUMMY_EMSCRIPTEN_ROOT}']
     asflags = get_base_cflags(preprocess=False)
     input_files = self.get_files()
     ninja_file = os.path.join(build_dir, 'build.ninja')
@@ -494,9 +497,9 @@ def build_objects(self, build_dir):
     if self.deterministic_paths:
       source_dir = utils.path_from_root()
       relative_source_dir = os.path.relpath(source_dir, build_dir)
-      cflags += [f'-ffile-prefix-map={source_dir}=/emsdk/emscripten',
+      cflags += [f'-ffile-prefix-map={source_dir}={DUMMY_EMSCRIPTEN_ROOT}',
                  f'-ffile-prefix-map={relative_source_dir}/=',
-                 '-fdebug-compilation-dir=/emsdk/emscripten']
+                 f'-fdebug-compilation-dir={DUMMY_EMSCRIPTEN_ROOT}']
     case_insensitive = is_case_insensitive(build_dir)
     for src in self.get_files():
       ext = shared.suffix(src)

tools/wasm-sourcemap.py

@@ -25,6 +25,7 @@
 sys.path.insert(0, __rootdir__)
 
 from tools import utils
+from tools import system_libs
 
 logger = logging.getLogger('wasm-sourcemap')
 
@@ -238,8 +239,8 @@ def read_dwarf_entries(wasm, options):
     for file in re.finditer(r"file_names\[\s*(\d+)\]:\s+name: \"([^\"]*)\"\s+dir_index: (\d+)", line_chunk):
       dir = include_directories[file.group(3)]
       file_path = os.path.join(dir, file.group(2))
-      if file_path.startswith('/emsdk/emscripten/'):
-        sub_dir = os.path.relpath(file_path, '/emsdk/emscripten')
+      if file_path.startswith(f'{system_libs.DUMMY_EMSCRIPTEN_ROOT}/'):
+        sub_dir = os.path.relpath(file_path, system_libs.DUMMY_EMSCRIPTEN_ROOT)
         file_path = utils.path_from_root(sub_dir)
       files[file.group(1)] = file_path